TIG welding requires pure argon gas, which will provide a clean weld with no oxidisation.

MIG welding requires an argon, CO2 and/or oxygen mixture for more penetration and heat.

Pure argon gas is needed when TIG welding because, as a noble gas, it doesn’t react to other elements during the welding process. That way, you’re left with a clean weld free of oxidisation and other defects.

A gas mixture is needed when MIG welding because the addition of CO2 and/or oxygen provides the necessary heat and penetration required for a successful weld. The only time you would need pure argon when MIG welding is if you’re working with aluminium.

Comparing the effects of different gases on weld quality

As demonstrated in our quick, thirty-second video, you can see the visual differences when using the wrong and right welding gas.

Pure argon in TIG welding: With pure argon in TIG welding, a nice, clean, unoxidised finish is achieved.

Argon mixture in TIG welding: Conversely, using an argon mixture intended for MIG welding while TIG welding can lead to subpar results, including defects within the weld that compromise its integrity.

Argon mixture in MIG welding: Using a gas mixture while MIG welding results in a hot, penetrating weld.

Pure argon in MIG welding: If pure argon is used in MIG welding, the result is a cold, non-penetrating weld. This highlights how pure argon is not suitable for MIG welding due to its inability to provide the necessary heat and penetration.

For the best results, make sure you’re using the right gas.

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Gasless MIG is almost identical to standard MIG except for the wire used. A hollow wire that contains flux, which produces a protective layer of slag on the finished weld, is used rather than a solid wire.

As the flux melts, it releases gases from within, which bubble to the surface. These internal gases protect the weld from outside contaminants until the puddle cools. This slag layer means a shielding gas isn’t needed for flux-cored welding. 

When it comes to gasless MIG, one of the most common mistakes beginners make is the technique they use to create the weld.

Push vs Pull

There are two different ways to create a weld: pushing or pulling.

The push technique is where the wire is located at the leading edge of the weld pool and pushed towards the not yet welded part of the joint. This technique offers a better view of the weld joint and direction of the wire into the weld joint. It directs heat away from the weld puddle, allowing faster travel speeds and providing a flatter and wider weld profile for minimal clean-up.

The pull or drag technique is where the torch and wire are pulled away from the weld bead. The arc and heat are concentrated on the weld pool. The base metal receives more heat, deeper melting, more penetration, and the weld profile is higher with more build-up.

When it comes to gasless MIG welding, you need to use the pull technique. While pushing is preferred for standard MIG as it keeps the weld pull properly protected with shielding gas, that’s not the case for gasless. Pushing a gasless weld runs the risk of leaving slag inclusions or other defects in the weld.

Flux-cored wires, similar to stick electrodes, should be dragged. That way, you eliminate any chances of weld defects in your joint.

We’ve demonstrated the difference in results in our quick thirty-second video above so you can see it for yourself.

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The drive rollers in a MIG welder work to pull the wire from the spool and feed it down the torch liner and out the torch tip. This is done by the drive motor in the unit, and the groove in the rollers provides tension to the side of the wire, allowing it to be pushed.

The tension knob is important because it determines how much pressure is applied to the wire while it’s in the groove of the drive rollers.

Why Is the Correct Tension Important?

Proper tension will give you a consistent wire feed and a stable arc.

If there’s not enough tension on your wire, it won’t feed properly. The wire will slip in the drive rollers, likely causing it to birdnest. Not enough tension will also make your arc stutter as the wire is what acts as the electrode, and if there’s not any wire being added and conducting, the arc will falter.

Too much, and it can flatten or deform your wire, causing feeding issues further down the torch and creating an unstable arc. Too much tension on the wire will also cause it to birdsnest at the rollers if something restricts your wire from feeding further down the torch.

Either way, you’re left with feeding issues, downtime and additional costs as you waste the torch length of wire each time a problem needs to be fixed.

How to Tension Your Wire

Method 1

To correctly tension your MIG wire (as different metal types can require different amounts of tension), follow these steps:

1. Start with a cold torch and feed about 50mm (5cm) hangs out of the end of the torch tip.
2. Decrease the tensioner arm by rotating anti-clockwise so that the wire slips (the rollers are spinning, but the wire doesn’t move) when the trigger is pulled.
3. Once the tension has been removed, you can then turn the tension level a half-turn clockwise to increase your tension, gripping the exposed wire between your thumb and forefinger with light pressure. Make sure you’re wearing gloves to do this, as the wire can get hot.
4. Pull the trigger while holding the wire. If it slips, repeat the process.

Keep adding tension until you can’t stop the wire with your fingers, and it feeds smoothly without slipping.

Method 2

The other way you can tension your drive rollers is with a wooden block. You’ll need a wooden block as it’s not a conductive material and your wire won’t try to weld to it. To tension your wire this way follows a similar process:

1. Start with a cold torch and feed about 50mm (5cm) hangs out of the end of the torch tip. Put a slight bend in the end of the wire.  
2. Decrease the tensioner arm by rotating anti-clockwise so that the wire slips (the rollers are spinning, but the wire doesn’t move) when the trigger is pulled.
3. Place your MIG torch roughly 20mm (2cm) above the block of wood and pull the trigger. The wire should start to curl against the wood until it starts slipping.
4. Turn the tension level a half-turn clockwise to increase your tension and start feeding the wire again. Repeat this process until the wire forms a 50mm (5cm) diameter circle against the block without the wire slipping.

Make sure not to put too much pressure on the wire, as it can flatten or deform it, causing feeding issues further down the torch. Too much tension on the wire will also cause it to birdsnest at the rollers if something restricts your wire from feeding further down the torch.

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HD Backlit Interface

The most apparent change to this machine is the brand-new, upgraded interface. It now comes with a large HD backlit interface. The clear colour screen is bright and easy to read, so navigating the screen and settings is much easier, especially in dark work environments and low light conditions. 

Optional Air Compressor Module

Every plasma cutter needs compressed air to run, and we’ve now built our own for your convenience. Our new air compressor module is designed to perfectly fit the RAZOR CUT 45. The sleek and compact unit eliminates the need for a large, bulky external air compressor. It’s ideal for workshops and garages where space is a premium or as a CNC companion.

The air compressor module will clean cut 6mm steel and 5mm aluminium.

Perforated Cut Mode

You’ll now be able to cut perforated and expanded metals just as easily as solid metals. When standard plasma cutting, the arc will automatically cut out if it can’t find metal to complete its electric circuit. That means when you’re trying to cut metal filled with holes and gaps, you’ll be constantly stopping and starting the arc over and over.

With the addition of perforated cut mode, you can now swap into this mode and have your arc stay stable and remain ignited, even when cutting over holes. Slice through mesh, grating and fencing and any perforated metal with ease.

Smart Fan

We’ve introduced an improved cooling system in this machine, and the new smart fan only turns on when the machine needs it, diminishing the noise in your work environment. It also reduces the number of contaminants and dust that get pulled into the machine, increasing the reliability and durability of the machine.

Check out the new RAZOR CUT 45 here

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Multi-Process Welding

As a three-in-one machine, the VIPER MULTI 195 MAX is capable of MIG, DC TIG and STICK welding. You won’t need to swap between different machines anymore, making setup a breeze and saving valuable time and effort without sacrificing quality.

4.0” Colour LCD Screen

With its intuitive controls and next-generation user interface, the clear colour screen makes changing your settings easier than ever.

100+ Smart-Set Programs

Setting up for a weld has never been easier. With over 100 synergic MIG and TIG programs, this machine is ready for every weld you want. Select your metal type, wire or electrode size, gas, and material thickness, and your machine is ready to go.

Power Factor Correction (PFC)

Get the most out of your machine with PFC. It maximises the electrical efficiency of the machine and automatically compensates for any voltage fluctuations, so you get more output power, and the internal components will last longer. Plus, PFC is designed to be generator friendly.

Dual Gas Inputs

The machine features dual gas inputs at the back, so you can have it set up to run MIG and TIG gases at the same time. Plus, they’re quick connect inputs, so you can plug in and unplug whenever you need to swap bottles.

Job Memory

The job memory feature lets you enter and store weld parameter settings under job numbers, and the weld parameters can be adjusted as needed. A total of 20 jobs can be stored for easy recall on the VIPER MLTI 195 MAX.

Complete MIG Weld Cycle Control

Get complete control over your MIG welds with a full set of adjustable parameters, such as pre- and post-gas flow, arc ignition speed, and burnback.

Arc Start

Starting a MIG weld has never been so smooth with the Arc Start dual function. You choose just how hot or cold you want your MIG weld to start. Start hot on thicker materials or cold on thinner materials you don’t want to burn through.

You can set the Arc Start above 100%, and the Hot Start will give you a boost in current at the start of your weld, eliminating issues with starting on cold metal and making welding on thicker materials easier.

Set it below 100%, and the Soft Start will help with edge arc ignition by starting at a lower current and ramping up when welding away from the edge.

Crater Fill

End your welds as strong as they started. The Arc End feature ramps your welding current and voltage down at the end of a MIG weld, so it fills in at a lower amperage, eliminating craters and pinholes.

The ‘Arc End’ feature operates the same way standard ‘Crater Fill’ functions do.

Inductance Control

Pick your preferred arc characteristics with the Inductance settings. By changing the frequency of your short circuit MIG welds with the Inductance controls, you can choose your arc characteristics on every weld.

Digital Geared Wire Drive

Experience unparalleled accuracy with our all-new digital geared wire drive system. Designed to sustain a consistent arc in varying conditions and with different wire types, it ensures an accurate wire feed speed. With this system, achieving precision on every welding task is effortless.

Gas-Shielded and Gasless Wires

Run both gas-shielded and gasless MIG wires, so whether you’re working with mild steel, stainless steel, aluminium, or flux-cored wire, the VIPER MULTI 195 MAX has got you covered.

DC High-Frequency TIG

Maximise your results from start to finish. A high-frequency torch can start an arc without contacting the workpiece, reducing the risk of contaminating the tungsten or the weld. It also means you get access to the entire TIG weld cycle, including pre- and post-gas and up and down slope parameters.

Pulse TIG

Minimise the heap input without compromising on any of the penetration. As well as the full weld cycle, the VIPER MULTI 195 MAX can also pulse TIG weld. Alternating between a peak and base amperage reduces the amount of heat input and focuses the arc, perfect for sheet metals and out-of-position welding.

Heat Control Trigger (HCT) Mode

The Heat control Trigger Mode is great for manual heat input control as you go. It lets you set a base current, which you can switch to at any time during a weld by pressing the trigger button.

MMA (STICK)

On top of MIG and DC TIG, the VIPER MULTI 195 MAX can also stick weld, and comes packed with additional stick features like Hot Start, Arc Force, Anti-Stick and Pulse.

Arc Force

The Arc Force feature helps to keep the arc stabilised throughout the weld by increasing or decreasing the peak current to compensate for your arc length, preventing the arc from cutting out or the electrode from sticking.

Hot Start

The Hot Start feature gives a boost of current at the beginning of your weld, stabilising your ignition and eliminating any issues with striking an arc, especially on difficult electrodes.

Anti-Stick

The Anti-Stick feature, which is always on, prevents your electrode from sticking to your workpiece. When the machine detects sticking, the current will drop significantly, so the electrode can be removed.

Pulse MMA

Pulse MMA (STICK) welding helps reduce spatter, improves heat control and allows for easier slag removal. It also improves the speed and efficiency of vertical up welds by eliminating the use of the ‘Christmas Tree’ technique while maintaining root fusion.

Foot Control Ready

The VIPER MULTI 195 MAX supports the connection of both a wired and wireless foot control for extra versatility and convenience while welding. You can adjust your amperage hands-free to avoid disrupting your torch movement, and the wireless option reduces cables and adds greater manoeuvrability.

Spool Gun Ready

This machine is spool gun ready, so you can attach a spool gun to run softer core wires like aluminium MIG wire. You don’t need to change the setup of your existing torch or drive rollers. The spool gun lets you quickly switch over to get any job done with no downtime.

10A Plug

Plug in and play. The 10A power plug can be used on any domestic outlet, so it’s perfect for the DIY home handyman or the professional welder looking to take it anywhere.

Smart Fan

The Smart Fan diminishes noise, saves power, helps reduce energy costs, and minimises the number of contaminants being pulled through the machine.

Generator Compatible

The VIPER MULTI 195 MAX can be connected to a generator, so you can take it anywhere. We recommend one with an 8.5kVA rating.

Check out the VIPER MULTI 195 MAX

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1. Prep your metal properly

One of the most important things to do when working with aluminium is to clean it thoroughly. It’s not a forgiving metal, so any dirt, oil, paint, etc., is going to give you problems.

First things first, get yourself a dedicated stainless steel wire brush for your aluminium and brush your joint clean. You’ll want a separate brush for your aluminium as you don’t want to grind contaminates from other metals into the plate you’re trying to clean.

The cleaner your metal is, the better. Once you’ve wire brushed the metal, wipe it down with acetone or isopropyl alcohol to remove as much of the oxide layer as possible.

Once your metal is clean, the next step is fitting up the joint. You want your two pieces to be completely flush. You shouldn’t have any overlapping corners or gaps, as these will make getting a weld more difficult.

2. Preheat your metal

When working with thicker sections of aluminium or in a cold climate, preheat your metal. Starting off cold can make it much harder to get a good weld on aluminium, so heating it with an oxy torch makes it much easier to get full penetration through the joint.  

3. Use aluminium-specific parts

When welding aluminium with a standard MIG torch, you’ll want to swap all your parts out to aluminium-specific ones. That way, you have the best chance of getting the wire to feed well.

To start with, if you can, get yourself a 3m torch. The shorter the distance the wire needs to travel, the better it’s going to go because there’s less space to run into issues.

Next, swap your steel liner out for a Teflon liner. Teflon liners are designed to feed aluminium, and they’re made of smoother material to minimise friction and resistance and keep the wire from catching on the inside.

While installing the Teflon liner, you’ll also need a neck spring. The neck spring attaches to the torch end of the liner to help with heat control as the wire exits the torch.

You’ll also need to swap your drive rollers out to U groove rollers, as they have a smoother curve in the bottom than V groove rollers. The U-shaped groove minimises the risk of the wire deforming that you could face when running aluminium through the sharper V groove roller.

Lastly, swap your torch’s standard contact tip for an aluminium contact tip. The borehole at the end is slightly wider in comparison to the same size steel tip. Aluminium expands when heated, so the bigger hole helps keep it from getting stuck or catching as it exits the torch.

4. Adjust into spray transfer

When welding aluminium, you want to crank your voltage and move into the spray transfer mode, which provides a hotter, smoother weld with less spatter. The thicker the metal you’re welding, the heavier the spray should be.

Aluminium is a good heat conductor, so it sucks the heat out of a weld faster than mild steel does, especially on thicker sections. Using a hotter transfer method means it’s easier to get a good weld.  

5. Always push the weld

Aluminium has to be pushed. Generally speaking, all of your MIG welds should be pushed (unless you’re using flux-cored wire), as pulling provides no penetration and less gas coverage. But it is especially critical when MIG welding aluminium.

Because you’re MIG welding, you miss out on the full cleaning action that’s available with an AC TIG weld. That makes the argon that shields your weld extra critical, so it needs to be out in front of the leading edge of the weld puddle.

Dragging your torch while welding aluminium can leave you with a lot of tiny porosity holes. When you’re dragging your torch, the gas lags behind, so all those contaminants that should’ve been removed before you got there are sucked into the puddle.

6. Fill in your craters

It’s super important to fill the end of any weld, but especially aluminium, as it’s extra susceptible to thermal shock and cold cracks.

If your machine has a crater fill option, like the RAZOR 200 PULSE, set it so that the end of your weld is properly built up and there are no craters or holes that can cause cracking later on.

If your machine doesn’t have a crater fill setting, you’ll need to do it manually.

To do this, one option you can use is the back-step method. When you reach the end of your weld joint, move back by a few millimetres; that way, the weld isn’t terminated right on the edge, and there’s a proper build-up of metal.

Another option, though it might not always be possible, is to use run-on and run-off plates. The plates are attached to either side of the weld joint and used to start a weld, eliminating any cold start issues, and to end a weld, removing any chance of having a crater.

Once the weld is done, you can snap or grind the run-off plates off, and you’re left with the best part of your weld and no craters.

The last option is to pause at the end of the weld, adding extra metal before releasing the trigger, filling the end of the weld to stop a crater from forming. 

7. Use the stiffer wire

When welding aluminium, you’ll need to use filler wire that’s compatible with your parent metal. Where possible, though, try and use 5356 filler wire rather than 4043.

5356 isn’t quite as soft as 4043; it bends less, so it’s easier to feed, especially when it needs to travel the length of a MIG torch.

However, if you’re welding on 4000-grade aluminium, you won’t be able to use 5356.

8. Straighten your torch lead

It sounds super simple, but it makes a massive difference to how well the wire will feed if the torch lead is curled, looped or kinked compared to when it’s straight.

9. Get a Spool gun or Push-Pull gun  

If all else fails when trying to weld aluminium with your MIG machine, you can look to get a spool gun or a push-pull gun, both of which are specifically designed for this application.

A spool gun cuts the feeding distance from several metres (3m-5m depending on your torch) down to roughly 50mm. By moving the spool roll from inside the machine to directly on the torch itself, there’s less chance of feeding issues because of the short distance it needs to travel. 

If you’re looking at doing production work where you’ll need to do a lot of aluminium welding, you can also look at getting a push-pull gun. The wire spool is still loaded in the machine, but there is a second small motor in the torch itself, which helps to pull the wire from the machine, making feeding more consistent.

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1. Fix your joint fit up

It might not seem like a big deal, but when you’re tacking pieces together while prepping a weld, how well they’re joined makes a difference.

When fitting up a joint, it’s important to make sure that everything lines up evenly. You don’t want one corner of a joint to be perfectly flush while the other end is way off. A small gap or slowly widening joint can cause issues as you try to weld over it and fill it in.

Gaps in your fit-up make it much easier to burn through, so double-check that everything is lined up nice and even before you go ahead with the proper weld for the best results.

2. Use MIG wire as filler rod

If your filler rod is too thick compared to your base metal, it isn’t going to get hot enough to melt. Your base metal will melt (and likely blow through) before the rod starts to melt. You’ll find that your filler balloons or balls up at the tip before falling into the weld pool, and generally won’t feed very well.

If you’re welding on really thin material, and the 1.6mm rods are still too thick, make yourself some filler rod using a length of MIG filler wire. MIG wire spools are precision wound, so the wire won’t be straight when you cut lengths off the spool, but you can fix that fairly easily.

Clamp one end of the wire in a vice (or another clamp system) and the other end in a drill. Stretch the wire so that it’s pulled straight and, pulling on it to keep it taut, start drilling. “Drill” the wire until it snaps at the end, and you’ve got a piece of straightened MIG wire. Cut off the curly end that’s left over from the drilling, and it’s ready to be used as a TIG rod.  

3. Clean your tungsten and consumables

If you’ve dipped your tungsten, or it’s become oxidised, grab a new one. Even a tungsten that hasn’t been dipped can be dirty, which can cause serious issues with your arc starts. Even if you haven’t dipped it, if you notice your arc deflects and wanders as you start a weld, grab a new one.

As well as your tungsten, you want clean consumables. Use the end of your tungsten or a wire brush to scrape out any spatter that may be on your gas lens or inside the cup. Spatter or other bits stuck on either can cause gas deflection, which means it won’t come out evenly, leaving parts of your weld vulnerable to the atmosphere.

Keeping your consumables clean will prevent contaminants from being blown into your weld and keep your gas where it’s meant to be.

4. Is your AC balance correct?

The AC balance of a machine is the amount of time spent in the negative and positive parts of the AC cycle. A general setting that will work for almost every weld is a 30% positive and 70% negative ratio.

If you have too much negative balance selected, you’ll find you get a weld that looks dirty, crusty, or frosty, and it isn’t the gas causing the issue. It can also misshape your tungsten, which will lose its tip and deform into a weird shape.

If your balance is too far on the positive side, your tungsten will turn into an excessive ball shape very quickly. The arc will usually flutter wildly before the tip of the tungsten melts off entirely into the weld pool, contaminating your weld.

5. Adjust your frequency to suit the job

Most inverter machines these days can adjust their welding frequency (or Hertz), which you should do to suit the metal thickness you’re working with.

A higher frequency, like 120Hz, will narrow your arc, giving you a tighter weld, great for welding in corners or on thinner materials. However, a higher frequency also gives less penetration.

A lower frequency, around the 50-90Hz range, will give you a wider arc and, therefore, a wider weld pool with more heat and penetration.

The standard base setting is usually around 60Hz, which is a good all-around setting that works for almost everything, but it can be finetuned to get an even better weld.

6. Clean your aluminium, and then clean it again

So many of the most common issues people run into when trying to weld aluminium can be caused by insufficient metal prep. It can be time-consuming to thoroughly clean all your metal, especially on big projects or lots of small repetitive welds, but it’s more time-consuming to redo failed welds.

There are a few steps to take to get your workpiece as clean as possible. First, wire brush the joint lengthways, preferably in only one direction, making sure to brush all the way off the edge to expel all the contaminants you’re removing. Use a dedicated stainless steel wire brush to avoid brushing bits of contaminant from other metals into the aluminium.

The next thing to do is run a scotch bright pad over everything to be extra sure it’s clean. (This step is optional.)

Finally, to make sure everything is spick and span, wipe your aluminium down with acetone (or rubbing alcohol) and a clean rag to remove the oxide layer.

7. Double dip your tacks

Don’t start your welds from a bad tack. If your tack has melted off part of the base metal and your starting point isn’t great, getting a good weld going will be a challenge.

You want a good foundation to start your puddle from, so make your tacks nice. If they’re just slapped on there, or they’re too big, or too much base metal has melted away, or it’s hanging over the edges, it’s going to make it harder to get a nice weld.

Aluminium doesn’t like being autogenous (fusion) welded, so it’s best to make your tack using filler, dabbing enough to fuse the joint without it being too big. Then add another dab, creating a tack that’s the same size as you want your weld bead, so it’s much easier to come back and start a nice puddle. It should almost look like the start of a weld rather than just a simple tack.

Add extra filler to your end tack as well, so you’ve got extra ‘meat’ when you reach the end of the joint. That way, you won’t have to worry about it blowing out at the hottest part of the weld as you finish.  

If you’ve done your tacks and they haven’t turned so great, you can neaten or feather them out with a grinder, or just remove them entirely and try again.

8. Take your time at the start

Don’t just arc up and go. Your weld won’t have time to pool properly, the filler isn’t going to wet in properly, and it’s not going to give you the start you want.

Instead, start the arc and then pause. You want to let your puddle establish before you start going. Wait for a few seconds, let the cleaning action happen, then add a bit of filler as it starts to form a puddle, letting everything sit down properly and blend into the base. Once it’s about the size and shape you want, you can go ahead and start adding filler and go along the weld.

Aluminium needs some extra time to form a weld pool, as the arc needs to first clean through the oxide layer before it can start puddling. Pause for a few extra seconds than you would with steel to let a proper puddle form before you start moving along the weld.

9. Use the right amount of filler material

Your filler rod can have an effect on the heat of your weld. Because the filler rod is cooler than the weld pool, each time you dab, it slightly cools your puddle.

If you don’t use enough filler, especially at the start of your weld, you can overheat your plate.  

On the other hand, using too much filler can cause your weld bead to build up on itself, and it won’t blend, leaving you with a lack of fusion both on the toes of the weld and in the joint itself.

You want enough filler to control the heat and get proper reinforcement but not so much that it chokes the weld.

10. Set your post flow for long enough

Not only does it protect the end of your weld while it’s still hot, but your post flow also works to protect your tungsten. Your tungsten, just like your workpiece, is red hot when you end a weld.

If your tungsten is exposed to the air while it’s still glowing, it can become contaminated, just like a weld would be. When you restart your arc, you’re going to blow all that oxidation and bits of contamination straight into the start of your next weld.

Set your post flow for long enough that your tungsten is shielded until it has cooled down. Ideally, your tungsten should remain shiny and silver after every weld. Hold your torch over the weld while the post flow is running, and keep your weld and tungsten protected from the atmosphere.

11. Read the puddle

Learning to read the weld puddle will allow you to course correct it as you go and give you a good indication of whether the weld is doing what it’s meant to.

One way to tell that you’re getting sufficient penetration is by watching the puddle. Is the weld pool sinking down into the plate? If it is, that usually means it’s penetrating all the way through.

12. Extend your arc as you add filler

The general rule of thumb when it comes to standoff distance when TIG welding is you’re your tungsten should be roughly the same distance from the plate as its width. For example, when using a 2.4mm tungsten, your standoff should be approximately 2mm.

It can be difficult to maintain that distance while adding filler without dipping the rod straight into the tungsten itself. To avoid this, you can lift the torch up slightly (by 1mm or 2mm, you don’t want to lose your gas coverage or arc stability) as you dip the filler rod and then lower it back to normal to maintain penetration as you advance the weld bead.

By moving your torch out of the way as you feed in rod, you remove the risk of contaminating your tungsten by touching the filler to it or by accidentally dipping it into the growing puddle. It can take a bit of practise to get the timing perfected, though.

13. Polish your welds if they’re going to be visible

You can purchase aluminium polish, so if you have a weld that will be visible or not painted over, you can polish it up to make it extra shiny. Tape around the edges of your weld and polish away. While polishing away, it can look rather dirty, but once you’ve wiped it down, you’ll be left with a gleaming weld ready to show off.

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We’ve made a step-by-step guide on everything you need to set up your MIG welder for a seamless aluminium weld.

Before you start welding aluminium

Aluminium is a considerably different metal compared to mild steel, which is why welding it can be more difficult. Some of its properties pose a direct challenge, including its softness, its thermal conductivity and its melting temperature, to name a few. 

Aluminium is highly thermally conductive. That means it is very good at drawing heat away from the weld pool and does so faster than mild steel. It can be hard to maintain a weld pool and get proper penetration in your joint without distorting the metal or blowing straight through on thinner pieces.  

Its high thermal conductance also makes starting a weld difficult, as your metal is usually at its coldest (unless you’ve preheated it).

As well as being more thermally conductive, aluminium’s melting temperature is 660°C, compared to mild steel’s 1350°C-1530°C. While its melting point might be less than half of steel’s, aluminium has an oxide layer that needs to be penetrated. The oxide layer has a melting point of 2000°C, which is what causes the problem.

Igniting an arc and producing a weld bead that doesn’t look too bad at the start takes some practice.

The best way to MIG weld aluminium is with a pulse MIG welder, like the RAZOR 200 PULSE. Pulse welding and features like start current or hot start, start slope, end current and end slope all give you more control over your arc and the heat input. The added control helps with starting a weld on cold metal and reduces defects like craters at the end. Pulse welding also almost completely eliminates spatter.

Unfortunately, pulse MIG machines are often more expensive and require more experience to master. Fortunately, you don’t need a pulse MIG machine to produce a good aluminium weld with your MIG welder.

With the right setup and technique, you can weld aluminium with a standard run-of-the-mill MIG welder. These days, almost all MIG welders are inverter machines, especially single-phase machines, so they’re much easier to use and better at welding aluminium than the older transformers.

The only limitation you’ll run into when MIG welding aluminium is the metal’s thickness. The thinnest most MIG welders can successfully weld is roughly 2mm. Anything thinner, and you’ll need to look at getting a pulse MIG or an AC/DC TIG welder with pulse capabilities.

Do you need a spool gun to MIG weld aluminium?

The short answer is no. If you don’t have (or don’t want) a spool gun, you can still MIG weld aluminium. While a spool gun is designed to make the whole process easier, your MIG welder and the standard torch it comes with are just as capable of getting the job done.

Spool guns can speed up your set up time and reduce the distance your wire needs to travel, but they also have their downsides. They’re bulkier and heavier, which makes them more uncomfortable for extended periods. They can also only be loaded with 0.5kg aluminium spools, so you’ll need to swap spools often if you’re doing a lot of welding.

Do you need AC to MIG weld aluminium?

No, you don’t. Alternating Current (AC) is only required when TIG welding aluminium. Almost all MIG welders operate on Direct Current (DC) only, which will work to weld both aluminium and steel.

Setting up your MIG welder

First things first, make sure you have a welder that can be set up for aluminium. It won’t be possible if your machine has a direct connect torch (like the VIPER MULTI 135). You’ll have too many issues trying to feed the filler wire through the torch’s steel liner.

However, if you have a Euro connect torch and can change the MIG liner in it, you’ll be able to set your machine up for aluminium with relative ease.

Choosing an aluminium filler wire

When it comes to choosing a wire for your weld, like all welding, one of the things you need to do is match your metal grades. There are two main filler wire grades you can get: 4043 and 5356. These aren’t the only available fillers, but they’re the most common.

They’ll work with most aluminium grades, so you can use them even if you’re not sure what metal grade you’ve got.

• 4043 is used on 4000 to 6000 series aluminium and contains silicon
• 5356 is used on 3000, 5000 & 6000 series aluminium, is marine grade and contains magnesium

Both fillers are aluminium alloys, with 4043 containing 5% silicon and 5356 containing 5% magnesium. The different makeups of each wire give them slightly different characteristics.

The most notable difference is that 4043 wire is softer than 5356 wire. Because 5356 wire is harder, it’s generally preferred when MIG welding, as it tends to feed better. However, if you’re welding a 4000 series aluminium, you’ll have to use 4043 wire.

Once you’ve got the right wire type, you’ll need to get the correct diameter size. Aluminium wires, both 4043 and 5356, are softer than mild steel, so the smallest wire size you can feed through a MIG torch is 1.0mm thick. The other common aluminium wire size is 1.2mm.

0.8mm-0.9mm wires are too thin to be fed through a MIG torch regardless of the prep. The softness of the wire makes it very prone to birdnesting, and running the smaller sizes only makes this worse. However, you can use 0.8mm-0.9mm wires in a spool gun.

Needing 1.0mm wire for your MIG torch does mean that your minimum base metal thickness is 2mm. Anything thinner, and you’ll want to TIG weld it or look at getting a pulse MIG.

MIG torch setup to weld aluminium

If you’re regularly swapping between steel and aluminium, you might want to consider getting a second torch. That way, you won’t have to continually swap out the internal parts and only need to swap between the torches.

Having a second torch just for your aluminium could save you a lot of time that would’ve otherwise been spent setting up.

Whether you get a second torch or not, here are the things that need to be changed for the best chance at smooth feeding.

Torch length

First things first, use the shortest MIG torch you have. If the only torch you have is over 4 metres, your best bet will be getting a new one entirely.

The further the aluminium has to travel, the more friction is placed on the wire, increasing your chances of running into feeding issues.

The best torch length for welding aluminium is 3m, although you can also use a 4m torch. The key is to keep the torch lead as straight as possible while the wire is being fed.

If you need a longer reach than 4 metres, you’ll need to look at getting a spool gun or push-pull gun. These guns come with 6m or 8m leads, and they’re both designed to weld aluminium.

Torch liner

When working with aluminium, you’ll need to change your torch liner. Over time, your regular steel liner becomes filled with steel shavings from the filler metal, which can cause problems. Using your steel liner usually results in wire feeding issues, or it could contaminate the weld.

That’s why you’ll need to change out your liner for a Teflon one. These are basically the same as your standard liners, but they’re made with a different material. The Teflon material offers less resistance, so your aluminium feeds smoothly.

Like with all liners, it will need to match the size of your filler. In the case of aluminium, you’ll probably always want a red one for 0.9mm-1.2mm wire sizes.

On top of the different liner, you’ll also need to attach a neck spring to the front end of it when you change it out. The neck spring keeps the liner rigid, which makes it easier to feed into the torch.

Not sure how to change your liner? Check out our step-by-step guide on changing a MIG liner.

Contact tip

The last thing that should be changed on the torch is the contact tip. Standard steel contact tips are too small for aluminium wire. As the aluminium heats up, it expands more than steel, so the borehole in a standard steel tip is too small, and the wire can’t feed.

There are two ways you can work around this. The first (and better way) is to get yourself some aluminium-specific contact tips. A 1.0mm aluminium tip has a bigger opening hole than a 1.0mm steel tip, removing the issue of the wire not fitting.

The other option is to use a steel contact tip that’s one size up from the size of your wire. However, this isn’t as reliable, and you might run into some problems with the wire not becoming conductive.

Guide tube

Depending on the machine, you may also need to change out your guide tube. The guide tube is the round, hollow tube between the front panel where the torch connects and the drive rollers.

On some machines, this can’t be removed or changed, but if it can, then you should replace it with an aluminium one. The guide tube can generally be removed with a pair of long-nose pliers, and then a new one can be slipped in.

Aluminium-specific guide tubes give the filler wire extra support between the rollers and the start of the torch, eliminating one of the most common spots that causes birdnesting. Like aluminium contact tips, the opening in the tube is wider, allowing the wire to expand as it heats.

Drive rollers

Next up are your drive rollers. You’ll need U groove rollers for your aluminium wire. Unlike the V groove steel rollers, the smooth, curved bottom of the U groove gives more grip on the wire without any distortion.

Because U groove rollers provide a more conformed grip to the profile of the wire, you don’t need as much tension on the wire.

Roller tension

Make sure your tension on the wire drive rollers is correct. As with any wire, having too much tension on them will distort your wire out of shape, which will cause issues as it drags inside the liner. On the other hand, not enough tension will leave your wire slipping.

You can check the tension on your rollers by feeding the filler wire through your fingers (with gloves on). Start with the tension so loose that the wire is slipping, and then work your way down the adjustment knob (gaining more and more tension). Your tension is correct when the wire feeds smoothly through your fingers while gripping it lightly.

That’s all of the internals sorted. Now you can feed the wire into the inlet guide, over the rollers and into the beginning of the guide tube. If you run into any issues, give our troubleshooting wire feeding guide a run-through.

Using a spool gun to weld aluminium

A spool gun isn’t essential, but it is designed specifically to weld aluminium.

Rather than feeding your wire through a long torch lead, the spool holder is attached to the gun. It reduces the wire’s travel distance from 3 or 4 metres down to approximately 30cm (from spool to weld pool). It also comes with its own mini geared drive roller system in the torch, which helps to feed the wire smoothly.

Spool guns completely eliminate birdnests and wire kinking, the two biggest issues you’ll face when it comes to MIG welding aluminium. They also come with a longer lead, which gives you more flexibility and movement from your machine.

On the other hand, they can only house 100mm wire spools. Housing the spool on the torch can make them heavy, fatiguing your hands faster because of the wire spool you’re holding.

The spool housing also makes the torch bulkier than a standard MIG torch. It can be harder to get into tight spots or corners without being at an awkward angle or losing your gas coverage.

They’re also an extra expense, more so than a new torch liner, contact tips, and drive rollers.

If you do want to run a spool gun on your welder, check that your machine has the necessary connections for it, as not every MIG welder does.

If you need help getting your spool gun up and running, we have a step-by-step setup guide here.

Gas

Whether you use the standard torch or a spool gun, MIG welding aluminium requires pure argon gas. Using a standard argon/CO2 gas mix on aluminium will leave you with a contaminated weld full of oxides and porosity.

Polarity

Aluminium MIG welding is done in positive polarity, or DCEP (Direct Current Electrode Positive). To set up a UNIMIG welder for DCEP, plug the polarity cable into the positive (+) panel mount and the earth clamp into the negative (-) panel mount.

Additional features for better aluminium welds

For the best possible starts and ends on your aluminium MIG welds, having a machine that comes with a few extra controls can help.

Inductance

The inductance setting on a MIG welder gives you more control over your arc. It controls how fast the current rises to reach the amps that you’ve selected. Instead of instantly reaching the maximum amperage (which would be quite violent), there’s a (very short) time delay between the starting point and reaching your max amperage.

A high inductance will give you a soft, fluid weld pool that wets into the toes well. It also reduces the amount of spatter produced and improves the appearance of your weld.

A low inductance will give you a narrower weld pool that freezes faster. It’s good for pin-pointing a weld, especially on thinner metal, but it can produce more spatter.

Hot Start

The hot start feature on a MIG welder will allow you to add a boost to the welding current at the start of your weld. It works to eliminate issues with starting on cold metal, which is very useful when you’re trying to start a weld on cold aluminium.

Crater Fill

The crater fill (or stop current) feature on a MIG welder lets you choose how hot or cold the weld will end, similar to the end amp setting on a TIG welder. By allowing the weld ramp down to a lower amperage and filling in the end of the weld, you reduce the chances of shocking the metal and being left with a crater or crack.

Post-Gas

The post-gas or post-flow setting lets you run gas over the end of your weld and keep it shielded from atmospheric contamination while it cools. Like with the stop current, this helps reduce your risk of shocking the metal and having a crater or crack form in the weld.

Not every MIG welder will have any or all these settings available, and you’ll likely need a pulse MIG machine to get all of them on a single machine.

Choosing a suitable machine to MIG weld aluminium

Every UNIMIG MIG welder can weld aluminium, but some are better than others. The only exception is the VIPER MULTI 135, which has a direct connect torch.

For a good, entry-level MIG welder that can also weld aluminium, check out the VIPER MULTI 165 and VIPER MULTI 185. These are small, portable, DIY machines that are easy to set up and use.

The VIPER MULTI 165 has built-in synergic programs and an inductance control, but it isn’t spool gun compatible. The VIPER MULTI 185, on the other hand, while it doesn’t have the additional settings, is capable of connecting a spool gun.

For a better, professional-grade MIG welder that can weld aluminium, check out the RAZOR MULTI 220 & 250. These machines are more powerful, so they can weld thicker material, and they both have inductance and post-gas settings available. They are both able to run a spool gun. Short of getting a pulse MIG, these machines are your best option for getting a standout weld on aluminium.

For the best aluminium MIG weld possible, check out the RAZOR 200 PULSE. With its single and double-pulse programs, you get fast, high-quality, aesthetic, spatter-free welds, and all on a single-phase 15amp plug.  

It may take some time to get all the necessary bits and pieces to swap over to aluminium, but once your machine is set up, you’re ready to go. The next step is making the weld.

Need some help with the actual weld? Check out our blog on how to weld aluminium.

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The post How to Set Up Your MIG Welder for Aluminium appeared first on UNIMIG.

HD Backlit Interface

The most apparent change to this machine is the brand-new, upgraded interface. It now comes with a large HD backlit interface. The clear colour screen is bright and easy to read, so navigating the screen and settings is much easier, especially in dark work environments and low light conditions. 

Synergic MIG Programs

We’ve loaded this welder full of synergic programs, so setting up for a weld has never been easier. Simply set your wire type, gas, wire size, and material thickness, and the machine will choose the optimal settings for your weld.

You can then manually adjust these settings up or down if they need a bit of tweaking to produce the perfect weld for your conditions.

Digital Control MIG Torch

Adding our brand-new digital control MIG torch with this machine means you can now adjust your settings from the torch itself. Remove the hassle of moving back and forth between your machine and the weld.

Easily fine-tune your amperage and voltage correction in synergic modes and your voltage and wire feed speed in manual MIG modes.

Foot Control Ready

With the foot pedal connection, you can take total control of your TIG welds. The foot pedal is the perfect accessory while TIG welding, letting you easily adjust your amperage as you weld. You won’t have to speed up, slow down, or worry about burning through or not getting enough penetration while welding. The foot control means you can adjust your heat to suit your weld every time. 

Advanced MMA Features

As a multi-process welder, our new RAZOR COMPACT 250 can also stick weld, a process which we’ve now packed with a range of advanced MMA features as well.

We’ve added an adjustable hot start designed to help with striking an arc. The hot start temporarily boosts the output current at the start, making striking an arc, even with difficult electrodes, much easier. You get smoother arc starts, improving the quality of your weld.

We’ve also added adjustable arc force, which adjusts the current (and, therefore, the heat) based on the length of the arc. When the arc becomes shorter, the current increases to keep it stable and stop the electrode from sticking. When the arc becomes longer, the current will decrease. The level of this response is what’s adjustable on the machine.

The adjustable arc force allows you to fine-tune your arc and improve your weld’s quality and consistency, especially in tight corners or when welding overhead or vertically.

The machine also now comes with built-in anti-stick, a feature that’s designed to keep you from ever sticking an electrode again, whether you’re at the start of a weld, halfway through or about to end one.

Smart Fan

We’ve introduced an improved cooling system in this machine, and the new smart fan only turns on when the machine needs it, diminishing the noise in your work environment. It also reduces the number of contaminants and dust that get pulled into the machine, increasing the reliability and durability of the machine.

Check out the new RAZOR COMPACT 250 here

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The post What’s New in Our New RAZOR COMPACT 250 appeared first on UNIMIG.

HD Backlit Interface

The most apparent change to this machine is the brand-new, upgraded interface. It now comes with a large HD backlit interface. The clear colour screen is bright and easy to read, so navigating the screen and settings is much easier, especially in dark work environments and low light conditions. 

Synergic MIG Programs

We’ve loaded this welder full of synergic programs, so setting up for a weld has never been easier. Simply set your wire type, gas, wire size, and material thickness, and the machine will choose the optimal settings for your weld.

You can then manually adjust these settings up or down if they need a bit of tweaking to produce the perfect weld for your conditions.

Digital Control MIG Torch

Adding our brand-new digital control MIG torch with this machine means you can now adjust your settings from the torch itself. Remove the hassle of moving back and forth between your machine and the weld.

Easily fine-tune your amperage and voltage correction in synergic modes and your voltage and wire feed speed in manual MIG modes.

4 Geared Wire Drive

Our RAZOR MULTI 250 now comes with a four-geared wire drive system. By adding an extra set of rollers to the geared wire drive gives you even more pushing power and improves the feeding, so you get a more efficient, consistent, and smooth wire-feeding experience, even when using a longer torch.

Foot Control Ready

With the foot pedal connection, you can take total control of your TIG welds. The foot pedal is the perfect accessory while TIG welding, letting you easily adjust your amperage as you weld. You won’t have to speed up, slow down, or worry about burning through or not getting enough penetration while welding. The foot control means you can adjust your heat to suit your weld every time. 

Advanced MMA Features

As a multi-process welder, our new RAZOR MULTI 250 can also stick weld, a process which we’ve now packed with a range of advanced MMA features as well.

We’ve added an adjustable hot start designed to help with striking an arc. The hot start temporarily boosts the output current at the start, making striking an arc, even with difficult electrodes, much easier. You get smoother arc starts, improving the quality of your weld.

We’ve also added adjustable arc force, which adjusts the current (and, therefore, the heat) based on the length of the arc. When the arc becomes shorter, the current increases to keep it stable and stop the electrode from sticking. When the arc becomes longer, the current will decrease. The level of this response is what’s adjustable on the machine.

The adjustable arc force allows you to fine-tune your arc and improve your weld’s quality and consistency, especially in tight corners or when welding overhead or vertically.

The machine also now comes with built-in anti-stick, a feature that’s designed to keep you from ever sticking an electrode again, whether you’re at the start of a weld, halfway through or about to end one.

Smart Fan

We’ve introduced an improved cooling system in this machine, and the new smart fan only turns on when the machine needs it, diminishing the noise in your work environment. It also reduces the number of contaminants and dust that get pulled into the machine, increasing the reliability and durability of the machine.

Check out the new RAZOR MULTI 250 here

← See all articles

The post What’s New in Our New RAZOR MULTI 250 appeared first on UNIMIG.

HD Backlit Interface

The most apparent change to this machine is the brand-new, upgraded interface. It now comes with a large HD backlit interface. The clear colour screen is bright and easy to read, so navigating the screen and settings is much easier, especially in dark work environments and low light conditions. 

Advanced MMA Features

Our new RAZOR ARC 160 & 220 PFC now come with a range of advanced MMA features.

Hot Start

We’ve added an adjustable hot start designed to help with striking an arc. The hot start temporarily boosts the output current at the start, making striking an arc, even with difficult electrodes, much easier. You get smoother arc starts, improving the quality of your weld.

Arc Force

We’ve also added adjustable arc force, which adjusts the current (and, therefore, the heat) based on the length of the arc. When the arc becomes shorter, the current increases to keep it stable and stop the electrode from sticking. When the arc becomes longer, the current will decrease. The level of this response is what’s adjustable on the machine.

The adjustable arc force allows you to fine-tune your arc and improve your weld’s quality and consistency, especially in tight corners or when welding overhead or vertically.

Anti-Stick

The machine also now comes with built-in anti-stick, a feature that’s designed to keep you from ever sticking an electrode again, whether you’re at the start of a weld, halfway through or about to end one.

When the machine detects that the electrode is sticking, the current will shut off and unstick it.

Smart Fan

We’ve introduced an improved cooling system in these machines, and the new smart fan only turns on when the machine needs it, diminishing the noise in your work environment. It also reduces the number of contaminants and dust that get pulled into these machines, increasing the reliability and durability of them.

10A Plug

These machines come with PFC components, so now they both come with a 10 amp plug. Even the RAZOR ARC 200 PFC, thanks to its internals, is capable of outputting the same 200 amps as the previous model on a smaller plug. Now more portable than ever, you can run these machines on any domestic outlet, meaning you can use them just about anywhere.

Check out the new
RAZOR ARC 160 PFC & RAZOR ARC 200 PFC

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The post What’s New in Our New RAZOR ARC 160 & 200 PFC appeared first on UNIMIG.

HD Backlit Interface

The most apparent change to this machine is the brand-new, upgraded interface. It now comes with a large HD backlit interface. The clear colour screen is bright and easy to read, so navigating the screen and settings is much easier, especially in dark work environments and low light conditions. 

Advanced MMA Features

As both a TIG and stick welder, our new RAZOR TIG 220 DC now comes with a range of advanced MMA features as well.

We’ve added an adjustable hot start designed to help with striking an arc. The hot start temporarily boosts the output current at the start, making striking an arc, even with difficult electrodes, much easier. You get smoother arc starts, improving the quality of your weld.

We’ve also added adjustable arc force, which adjusts the current (and, therefore, the heat) based on the length of the arc. When the arc becomes shorter, the current increases to keep it stable and stop the electrode from sticking. When the arc becomes longer, the current will decrease. The level of this response is what’s adjustable on the machine.

The adjustable arc force allows you to fine-tune your arc and improve your weld’s quality and consistency, especially in tight corners or when welding overhead or vertically.

The machine also now comes with built-in anti-stick, a feature that’s designed to keep you from ever sticking an electrode again, whether you’re at the start of a weld, halfway through or about to end one.

Smart Fan

We’ve introduced an improved cooling system in this machine, and the new smart fan only turns on when the machine needs it, diminishing the noise in your work environment. It also reduces the number of contaminants and dust that get pulled into the machine, increasing the reliability and durability of the machine.

Power Factor Correction (PFC)

The addition of PFC in this machine means that it’s now running at maximum electrical efficiency. The internal components compensate for any voltage fluctuation, giving you increased efficiency, enhanced performance, and reduced power demand, so you get more output from the same input. Plus, it’s designed to be generator friendly.

10A Plug

With the added PFC components, this machine can output the same 200 amps of power as the previous model, but now on a 10 amp plug. More portable than ever, you can run this machine on any domestic outlet, meaning you can use it just about anywhere.

Check out the new RAZOR TIG 220 DC here

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The post What’s New in Our New RAZOR TIG 220 DC appeared first on UNIMIG.

HD Backlit Interface

The most apparent change to these machines is the brand-new, upgraded interface. They now come with a large HD backlit interface. The clear colour screen is bright and easy to read, so navigating the screen and settings is much easier, especially in dark work environments and low light conditions. 

Multi-Process Welding

These machines are no longer just MIG/STICK machines! Both the RAZOR MULTI 175 and 220 are now able to DC TIG weld, so you can now TIG weld mild and stainless steels as well as MIG weld them. You won’t have to swap between different machines anymore, saving valuable time and effort without sacrificing quality.

Trigger Controlled DC Lift Arc TIG

Now multi-process machines, the 175 and 220 are both capable of DC TIG welding. The Trigger Controlled DC Lift Arc means you can easily ignite your arc by tapping the tungsten to the workpiece and then lifting it up.

Lift Arc TIG is a much less aggressive process than traditional scratch start TIG, and so it reduces tungsten and workpiece contamination. Our Lift Arc technology also ensures that your tungsten tip won’t stick to the workpiece, preventing costly tip breakages.

The trigger control lets you start your gas flow with the press of a button rather than having to twist open a valve on your torch.

Synergic MIG Programs

On top of now being 3-in-1 machines, we’ve also loaded these two welders full of synergic programs, so setting up for a weld has never been easier. Simply set your wire type, gas, wire size, and material thickness, and the machine will choose the optimal settings for your weld.

You can then manually adjust these settings up or down if they need a bit of tweaking to produce the perfect weld for your conditions.

Digital Control MIG Torch

Adding our brand-new digital control MIG torch with these machines means you can now adjust your settings from the torch itself. Remove the hassle of moving back and forth between your machine and the weld. Easily fine-tune your amps and voltage correction in synergic modes and your voltage and wire feed speed in manual MIG modes.

Geared Wire Drive

Our RAZOR MULTI 175 and 220 now both come with a geared wire drive system. The added pushing power of a geared wire drive improves the feeding, so you get a more efficient, consistent, and smooth wire-feeding experience, even when using a longer torch.

Foot Control Ready

With the foot pedal connection, you can take total control of your TIG welds. The foot pedal is the perfect accessory while TIG welding, letting you easily adjust your amperage as you weld. You won’t have to speed up, slow down, or worry about burning through or not getting enough penetration while welding. The foot control means you can adjust your heat to suit your weld every time.  

Advanced MMA Features

As multi-process welders, our new RAZOR MULTI 175 and 220 can also stick weld, a process which we’ve now packed with a range of advanced MMA features as well.

We’ve added an adjustable hot start designed to help with striking an arc. The hot start temporarily boosts the output current at the start, making striking an arc, even with difficult electrodes, much easier. You get smoother arc starts, improving the quality of your weld.

We’ve also added adjustable arc force, which adjusts the current (and, therefore, the heat) based on the length of the arc. When the arc becomes shorter, the current increases to keep it stable and stop the electrode from sticking. When the arc becomes longer, the current will decrease. The level of this response is what’s adjustable on the machine.

The adjustable arc force allows you to fine-tune your arc and improve your weld’s quality and consistency, especially in tight corners or when welding overhead or vertically.

The machine also now comes with built-in anti-stick, a feature that’s designed to keep you from ever sticking an electrode again, whether you’re at the start of a weld, halfway through or about to end one.

Smart Fan

We’ve introduced an improved cooling system in this machine, and the new smart fan only turns on when the machine needs it, diminishing the noise in your work environment. It also reduces the number of contaminants and dust that get pulled into the machine, increasing the reliability and durability of the machine.

Check out the new
RAZOR MULTI 175 & RAZOR MULTI 220

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The post What’s New in Our New RAZOR MULTI 175 & 220 appeared first on UNIMIG.

HD Backlit Interface

The most apparent change to this machine is the brand-new, upgraded interface. It now comes with a large HD backlit interface. The clear colour screen is bright and easy to read, so navigating the screen and settings is much easier, especially in dark work environments and low light conditions. 

AC Waveforms

You can now adjust your AC waveform on top of your AC frequency and balance. Completely customise your aluminium welds by switching between Sine, Square and Triangle waves to change the arc characteristics, bead profile and penetration to suit your needs.

You can check out our article Understanding Welding Waveforms for a deep dive into the different waveforms and their specific characteristics.

Mixed AC/DC

Get the best of both worlds with the addition of Mixed AC/DC. Mixed AC/DC welding combines TIG AC and TIG DC negative in the one weld.

There are two periods during a mixed weld. The first is the AC period, where the oxide film is broken, and surface impurities are flushed out. The second, the DC negative period, is where the arc becomes narrower and penetrative, with higher heat inputs.

There are quite a few benefits from this type of welding, including higher welding speeds and penetration, so you can weld on thicker materials and get a faster weld puddle on cold workpieces.

Advanced MMA Features

As both a TIG and stick welder, our new RAZOR TIG 200 AC/DC now comes with a range of advanced MMA features as well.

We’ve added an adjustable hot start designed to help with striking an arc. The hot start temporarily boosts the output current at the start, making striking an arc, even with difficult electrodes, much easier. You get smoother arc starts, improving the quality of your weld.

We’ve also added adjustable arc force, which adjusts the current (and, therefore, the heat) based on the length of the arc. When the arc becomes shorter, the current increases to keep it stable and stop the electrode from sticking. When the arc becomes longer, the current will decrease. The level of this response is what’s adjustable on the machine.

The adjustable arc force allows you to fine-tune your arc and improve your weld’s quality and consistency, especially in tight corners or when welding overhead or vertically.

The machine also now comes with built-in anti-stick, a feature that’s designed to keep you from ever sticking an electrode again, whether you’re at the start of a weld, halfway through or about to end one.

Smart Fan

We’ve introduced an improved cooling system in this machine, and the new smart fan only turns on when the machine needs it, diminishing the noise in your work environment. It also reduces the number of contaminants and dust that get pulled into the machine, increasing the reliability and durability of the machine.

Power Factor Correction (PFC)

The addition of PFC in this machine means that it’s now running at maximum electrical efficiency. The internal components compensate for any voltage fluctuation, giving you increased efficiency, enhanced performance, and reduced power demand, so you get more output from the same input.

Plus, it’s designed to be generator friendly. We recommend a 9kVA generator for this machine.

10A Plug

With the added PFC components, this machine can output the same 200 amps of power as the previous model, but now on a 10 amp plug. More portable than ever, you can run this machine on any domestic outlet, meaning you can use it just about anywhere.

Check out the new RAZOR TIG 200 AC/DC

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The post What’s New in Our New RAZOR TIG 200 AC/DC appeared first on UNIMIG.

SpotPlus (DC only)

The SpotPlus program, also known as speed start, speeds up the formation of the weld puddle. When turned on, it applies a synergic pulse program to the beginning of the weld. It can be set to run between 0 seconds to 60 seconds. When the time runs out, the machine will switch back to the standard parameters set for your TIG weld. 

The initial pulse that you set works to create the weld pool much faster than a standard start, as the vibration of the pulse speeds up the melting of the joint edges for quicker puddle formation.

It can be used to make faster tacks, or it can be used when stitch welding on thinner materials, as it reduces the heat in the metal, so you can stitch for longer. It is recommended for use on sheet metal and fit-ups with small gaps.

ArcPlus (DC only)

The ArcPlus program, also known as steady arc, automatically adjusts the welding current based on the arc voltage. If the arc voltage decreases, the machine increases the welding current, and if the arc voltage increases, the machine decreases the welding current.

When welding, adjusting the arc length can widen the weld pool, which will increase your heat input into the base plate. 

With ArcPlus, even when the length of the arc changes, the power remains constant. That means the size of the weld puddle remains the same, as does the heat input, which impacts the weld penetration.

When the voltage goes down, the amps will go up (and vice versa) to give a consistent weld puddle, a sharper arc and a constant heat input. Without any fluctuations in the weld current, you can weld faster.

It also lets you weld with a very short arc. The closer the tungsten gets to the workpiece, the more it increases the amperage, which prevents contact between the two and stops the tungsten from sticking or becoming contaminated.

You can set how sensitive the machine is to changes in arc voltage from 1A to 50A. For example, you could set it so that for every 1-volt variation, the machine changes the welding current anywhere from 1A to 50A.

If you set the sensitivity to 50A per 1 volt, this means that if the arc voltage drops by 1 volt, the welding current will increase by 50A. We recommend setting it between 1A-20A for thin materials and 20A-50A for thicker materials.

TackPlus (DC only)

The TackPlus program is a tack welding program with a preset weld time and adjustable frequency (0-6Hz) to create evenly spaced and sized fusion tack welds along a joint with minimal heat input.

You can adjust how often the tacks will occur, and the program will run until the torch trigger is released. The set amount of time for each tack means a filler rod can’t be used with this program, so it is mostly recommended for thin sheet metal. It minimises warping and other plate distortion that can occur on thin materials.

FusionPlus (AC only)

The FusionPlus program, also known as amplitude control, allows for a more penetrative weld while in AC. It works to adjust the percentage of the AC waveform that is on the negative side. Here, zero is a 50/50% AC waveform with equal amounts of EN and EP. 

By increasing the percentage of electrode negative, more heat is transferred to the base plate, allowing for greater penetration, a narrower arc and less cleaning (or ‘pickling’) around a weld. The increased EN percentage also allows for faster weld speeds and metal deposition. 

By decreasing the electrode positive percentage, it reduces the amount of heat in the tungsten, so your tungsten won’t ball up or deform as quickly. You’ll also be able to use smaller-sized tungsten electrodes for the same job, as the heat is off the tungsten and is precisely directed into the weld.

The narrower arc and greater penetration that FusionPlus provides means that you can weld on thinner materials with ease. However, it’s not recommended on thicker materials as the reduction of the positive won’t provide enough cleaning of the oxide layer during a weld.

Mix TIG AC/DC

Mixed AC/DC welding is the combination of TIG AC and TIG DC- in one weld. There are two periods during a mixed weld. The first is the AC period, where the oxide film is broken, and surface impurities are flushed out. The second, the DC- period, is where the arc becomes narrower and penetrative, with higher heat inputs.

There are quite a few benefits from this type of weld, including higher welding speeds and penetration, so you can weld on thicker materials, and a faster weld puddle on cold workpieces.

You can adjust the percentage of AC compared to the DC- during a full cycle from 0-80%. By adjusting this to 70%, you’ll have 70% of the complete cycle spent in the AC period, and 30% in the DC- period.

It’s a good idea not to have more than 50% DC-, as it could reduce the cleaning of the oxide layer by too much.

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It also comes packed full of features and functions so that you can get a perfect weld, every time.

MIG & AC/DC TIG: A True Multi-Process 

The RAZOR MULTI 230 AC/DC is a 4-in-1 machine. That means it can do every kind of welding there is. MIG, MMA, DC TIG, and, finally, AC TIG. That means you can now TIG weld aluminium on a MIG machine, making it a true all-process machine. 

It does high-frequency TIG, whether you’re in AC or DC. That means you have more control when starting or stopping the arc, and reduce the risk of contaminating the tungsten or the weld, so you’ll have no issues when it comes to aluminium. 

Plus, just because we’ve added another welding process doesn’t mean we’ve taken anything away. You get complete control over your TIG welds. Both the AC & DC TIG welding modes come with the full weld cycle. You can adjust all the parameters, like pre- and post-flow, up and down slopes, as well as all things pulse. 

It isn’t only TIG, the RAZOR MULTI 230 AC/DC also has a complete set of weld parameters for your MIG welds. You can adjust the parameters such as pre- and post-gas flow, arc ignition speed, and burnback. 

That’s not all. This machine supports both gas-shielded MIG and gasless MIG, meaning you can run mild steel, stainless steel, aluminium as well as flux-cored MIG wires.

No matter what kind of welding you’ve got planned, the RAZOR MULTI 230 AC/DC can do it. 

5” Colour LCD Screen 

With its intuitive controls and next-generation interface, the large, clear colour screen makes adjusting your weld parameters easier than ever. 

Dual Plug Compatibility (10A & 15A)

The RAZOR MULTI 230 AC/DC comes with the option to choose your power. The machine comes plugged with a 15 amp lead but if you don’t have a 15 amp outlet, don’t worry. With the 15 to 10 amp conversion lead, you can plug this machine into any domestic outlet as well. Just make sure to switch the machine output on the welder as well.

Power Factor Correction (PFC)

The PFC maximises the electrical efficiency of the machine and automatically compensates for any voltage fluctuations, giving you more output power and the internal components a longer life.

100+ Smart-Set Programs

The RAZOR MULTI 230 AC/DC comes with over 100 synergic MIG and TIG programs, ready for every weld you want. Select your metal type, wire or electrode size, and the gas, and your machine is set, and ready to go.

Dual Gas Inputs

The machine features dual gas inputs at the back, so you can have it set up to run MIG and TIG gases at the same time. Plus, they’re quick connect inputs, so you can plug in and unplug whenever you need to swap bottles. 

Arc Start 

Starting a MIG weld has never been so smooth with the Arc Start dual function. You choose just how hot or cold you want your MIG weld to start. Start hot on thicker materials or cold on thinner materials you don’t want to burn through. 

You can set the Arc Start above 100%, and the Hot Start will give you a boost in current at the start of your weld, eliminating issues with starting on cold metal, and making welding on thicker materials easier. 

Set it below 100% and the Soft Start will help with edge arc ignition by starting at a lower current and ramping up when welding away from the edge.

Crater Fill

End your welds as strong as they started with the Crater Fill feature. The Crater Fill ramps your welding current and voltage down at the end of a MIG weld, so it fills in at a lower amperage, eliminating craters and pinholes. 

The Crater Fill function is labelled ‘Arc End’ in the MIG settings.

Inductance Control 

Pick your preferred arc characteristics with the Inductance settings. By changing the frequency of your short circuit MIG welds with the Inductance controls, you can choose your preferred arc characteristics on every weld.

Geared Wire Drive

The machine comes with a geared roller drive unit, so you get a more consistent and smoother wire feeding experience. Plus, it helps when using a longer torch.

Advanced Plus TIG Programs

On top of the full TIG weld cycle, the RAZOR MULTI 230 AC/DC also comes with some extra TIG programs, so you can get professional results on any kind of weld. 

The SpotPlus program improves your spot or stitch welds by applying an adjustable synergic pulsed program. The program speeds up the spot tacking process and is perfect for sheet metal fitups with gaps.

The ArcPlus program keeps the volt amps constant by adjusting the welding current proportionally as the arc voltage increases or decreases during a weld. It helps give better puddle control when weaving, reduces heat input and increases side wall fusion.

The TackPlus program allows you to preset a tacking procedure to reduce the time required for tack welding, and also reduces the heat input in the joint between tacks, improving the quality.

The FusionPlus program is an advanced AC TIG feature that provides greater arc focus at high welding speeds and provides deep penetration even at low AC frequencies.

Mix AC/DC

Mixed AC/DC welding is the combination of TIG AC and TIG DC- in one weld. Mixed AC/DC gives you faster welding speeds, better penetration, a faster weld puddle on cold workpieces, and you can weld on thicker materials.

Tungsten Optimiser

The RAZOR MULTI 230 AC/DC comes with a Tungsten Optimiser setting, which optimises the arc ignition on AC TIG, based on the selected tungsten diameter. 

Heat Control Trigger (HCT) Mode

The Heat Control Trigger Mode is great for manual heat input control as you go. It lets you set a base current, which you can switch to at any time during a weld by pressing the trigger button. 

MMA (STICK) 

The RAZOR MULTI 230 AC/DC is a 4-in-1, so on top of MIG and AC/DC TIG, it also stick welds.  It’ll weld every kind of electrode, including cellulosic, and has a few additional STICK features like Hot Start, Arc Force, Anti Stick and Pulse. 

Hot Start 

The Hot Start feature increases the stability of your arc ignition and prevents a lack of fusion at the start of the weld. You won’t ever struggle to strike an arc again.

Arc Force

The Arc Force feature helps to keep the arc stabilised throughout the weld, by detecting any short circuits and increasing the peak current to prevent the arc from cutting out or the electrode from sticking.

Anti Stick

The Anti Stick feature prevents your electrode from sticking to your workpiece. When the machine detects sticking, the current will shut off and unstick the electrode.

Pulse MMA 

The RAZOR MULTI 230 AC/DC comes with a Pulse MMA (STICK) option. It helps reduce spatter, improves heat control and allows for easier slag removal. It also improves the speed and efficiency of vertical up welds by eliminating the use of the “Christmas Tree” technique, while still maintaining root fusion.

Spool Gun Compatible

This machine is Spool Gun ready, so you can attach a Spool Gun to run softer core wires like aluminium MIG wire. You don’t need to change the setup of your existing torch or drive rollers. The Spool Gun lets you quickly switch over to get any job done with no downtime.

Wireless Foot Pedal

This machine supports the connection of both a wired or wireless foot control for extra versatility and convenience while welding. You can adjust your amperage hands-free to avoid disrupting your torch movement, and the wireless option reduces cables and adds greater manoeuvrability as well. 

Smart Fan 

The RAZOR MULTI 230 AC/DC features a Smart Fan, which diminishes noise, saves power, helps reduce energy costs, and minimises the number of contaminants being pulled through the machine. 

Generator Compatible 

The RAZOR MULTI 230 AC/DC can be connected to a generator so that you can take it anywhere. We recommend one with an 8.5kVA rating.

Check out the RAZOR MULTI 230 AC/DC

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Our all-new RAZOR 200 PULSE welder has arrived. As the latest innovation in pulse MIG, this machine comes filled with revolutionary technology across the board. Whether it’s MIG, pulse MIG, double pulse MIG, High Frequency TIG, pulse TIG or STICK – you name it, the RAZOR 200 PULSE can handle it.

And that’s not to mention all the other features it comes jam-packed with. So, let’s go through everything the pulse MIG has to offer.

Single and Double Pulse MIG

First things first, let’s go over what pulse and double pulse welding is.

A single pulse weld alternates between a peak current and a background current.

Because of the addition of a background current, the heat input in the metal is reduced. That means you can weld softer and thinner materials than you could with standard MIG, perfect for all your aluminium welding. And don’t worry, you’ll still get full penetration, even on the thicker stuff.

Plus, say goodbye to your post-weld clean-up. Thanks to pulse MIG being a spray transfer, you’ll get all the benefits of spray, including an almost completely spatter free weld. There’ll be no need for your grinder anymore. 

That’s just the single pulse. Double pulse welding works the same way but with a second background current to add even more control over the arc. 

You’ll be able to produce a weld that looks just as good as a TIG weld in half the time. You get all the speed of a spray MIG weld with a final weld that looks like a stack of dimes. Great for the welds that won’t be seen, perfect for the ones that will. 

5” LCD Touch Screen Display

The large LCD touch screen means that choosing your weld parameters or changing your settings mid weld has never been easier. The five-inch touch screen display is clear, with a super easy to navigate interface. 

You can use the touch display, or you can opt for the control knobs to adjust your settings. But, regardless of how you use it, it’s so simple that you won’t even need a manual to work it out.

100+ Synergic Programs

The RAZOR 200 PULSE comes with over 100+ synergic programs across MIG, TIG and stick modes, so setting up for a weld has never been faster or easier. Select your metal type, wire or electrode size, and the gas, and you’re ready to weld.

Hot Start

With the Hot Start function, starting a MIG weld has never been so smooth.

Turn it on to give you a boost in current at the start of your weld, eliminating issues with starting on cold metal and making welding on thicker materials and aluminium easier.

Crater Fill

Finishing a weld has never been so easy with the Crater Fill feature. 

Turning the Crater Fill function on will ramp your welding current and voltage down at the end of a MIG or TIG weld, so you can fill your weld in at a lower power level, eliminating craters and pinholes. 

Now you can end your welds as strong as they started.  

GLICK Heat Control 

Those aren’t the only new technologies we’ve introduced with the RAZOR 200 PULSE. Try out GLICK on MIG or TIG welds. When using the GLICK function, set a base current, which you can switch to at any time during a weld by pressing the trigger button. GLICK is great for manual heat input control as you go. 

Inductance Control

Take complete control of your arc with the inductance settings. By changing the frequency of your short circuit MIG welds with the Inductance controls, you can choose your preferred arc characteristics on every weld. 

Adjustable Arc Length

You can increase or decrease your arc length while in the synergic and pulse MIG modes to suit your weld style. 

4 Geared Wire Drive  

The RAZOR 200 PULSE comes with four geared wire drive rollers, so you get a more consistent and smoother wire feeding experience on every MIG weld. 

Internal Accessories 

The internal housing features a storage space for any additional rollers you might have, so they’re always in reach. 

Plus, it has an internal spool light, so you get max visibility in any lighting. 

High Frequency DC TIG

Not just a MIG machine, you can maintain complete control over your TIG welds with the RAZOR 200 PULSE as well.

The high frequency DC TIG welding mode comes with a full set of adjustable parameters, like pre- and post-flow, up and down slopes, and all things pulse. Everything you need, right at your fingertips. 

STICK (MMA)

With the RAZOR 200 PULSE, you’ll be able to STICK weld anything. It can weld every kind of electrode, including cellulosic electrodes. 

It also comes with its own advanced parameters, including Anti Stick, Arc Force and Power Limit.

With the Anti Stick turned on, you’ll never stick an electrode again. 

The Arc Force function helps keep the arc stabilised throughout the weld so that it won’t cut out. It also helps to strike an arc by keeping the electrode from sticking. 

The Power Limit function works to keep the amperage constant throughout the weld by preventing the voltage from exceeding the set value. 

Job Memory (100 Jobs)

You can save up to 100 of your favourite weld settings with the jobs function. 

Digital Control Torch

With the digital MIG torch, you can adjust your amps, current, and voltage right on the torch itself. The DM26 Digital MIG Torch also comes pre-fitted with a carbon-polyamide liner, ready for aluminium.

Easy Switching

Instantly switch between welding modes. If you’ve got a MIG and a TIG torch plugged in, pressing the trigger on one of them will automatically switch you to the parameters screen of that welding mode. 

2T / 4T / SPOT

Choose between two-touch, four-touch and spot modes to maximise operator comfort on every weld. 

100mm & 200mm Spool Sizes

The RAZOR 200 PULSE can hold 0.5kg and 2kg aluminium spools and 1kg and 5kg mild and stainless steel spools.  

IP23S

The RAZOR 200 PULSE is rated IP23S, so it’s protected from touch by fingers and objects greater than 12mm, and water spray less than 60° from vertical. 

Generator Compatible 

Going off the grid? The RAZOR 200 PULSE can be connected to a generator. We recommend one with an 11kVa. 

Lightweight and Portable

Onsite or off, you can take this machine anywhere. 

Those are just some of the many features that the RAZOR 200 PULSE is chock full of. Grab one for yourself to find out what else the machine is capable of, or if you’ve got any questions, don’t hesitate to get in contact.

Check out the RAZOR 200 PULSE

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That’s why changing your liner as needed is essential. Letting your wire drag because your liner has kinked inside the torch is going to give you an erratic feed, which you don’t want.

Changing your liner is relatively easy, so when you do need to change it, here’s our step-by-step guide on how.  

What is a MIG torch liner?

The liner inside your torch guides the filler wire through your torch lead, and it ensures that the wire makes it out of the torch tip. Like with most things welding, your liner needs to match the type and size of your filler material.

If you’re using mild or stainless steel, you can use a standard MIG liner. If you’re using aluminium, you’ll need a Teflon liner.

Torch liners are also colour coded, so you can tell by sight whether it’s the one you’ll need for filler wire size.

These colours apply to both steel and aluminium liners. The main difference is the neck spring on the Teflon liners.

You may need to change your liner before you feed your wire through, as they’ll only fit specific sizes. You’ll also need to change your liner if it is clogged, damaged or kinked. Here’s how.

How to change a MIG torch liner

1. Remove the nozzle, contact tip, gas diffuser and tip holder from the front end of the torch.

2. Remove the liner retaining nut from the end of the torch.

3. Carefully pull out and completely remove the existing liner. Make sure the MIG torch is laid out completely straight when you do this.

4. Carefully feed in the new liner down the torch lead to the end of the torch neck.

5. Fit the liner retaining nut and screw it halfway down. Don’t tighten it yet.

6. Snip the excess liner off to just below flush with the torch neck. The liner should line up with the bottom of where the tip holder screws in.

7. Replace the front-end parts of the torch. If you can’t screw the tip holder back into place, the liner is too long and needs to be trimmed. However, don’t cut it too short, as leaving a gap between the liner and tip holder inside the torch will also cause issues.

8. Fully screw down the liner retaining nut and nip it up tight. This compresses the liner inside the torch cable assembly, preventing it from moving during use.

When you’re changing your liner, it’s best to keep the torch entirely straight and go slowly, as you don’t want to kink the liner itself.

Quick tip: Lay your new liner next to your old liner and use the older liner as a measurement guide, cutting the new one to the same length. That way, you can be sure that the liner will fit in the torch perfectly.

There are separate liners for steel wires and aluminium wires. If you’re going to use a standard MIG torch for an aluminium wire, you’ll need an aluminium specific liner (in the correct size).

How to change a Teflon liner

Replacing a Teflon liner (when working with aluminium) is mostly the same as replacing a steel liner, except there are a few extra steps.

Once the old liner has been pulled out, you’ll need to attach a neck spring to the top of the new liner before you can insert it. The neck spring keeps the liner ridged so it can be fed into the torch with no issues and keeps the wire from kinking. It also helps protect the liner from getting too hot and melting inside the torch.

The neck spring will butt up against where the tip holder screws in inside the neck of the torch. The excess liner will instead hang out the back of the torch (towards the machine side).

Depending on your machine, there are two things you can do with the excess.

1: If your machine has no removable guide tube inside the Euro connection, simply cut the excess off and screw the retaining nut back on.

2: If your machine has a guide tube that can be changed, swap it out for an aluminium specific guide tube, which is slightly larger.

The retaining nut can be screwed back into place with the excess liner hanging out the back of it. Don’t forget to move the collet and O ring so that they are clamped in place by the retaining nut when it’s screwed in.

Reattach the torch to the machine to make sure you can line the liner up correctly. Then, feed the excess liner through the guide tube and into the machine, where it will butt up against the drive roller and hang out past them.

Cut the liner to a length where it isn’t touching the drive roller, but it’s slightly protruding out the end of the guide tube still.

Having the liner go all the way to the drive roller (if possible) helps to stop potential birdnesting that might have occurred if the wire was free to bounce around in the open guide tube.

Finally, replace the front-end parts of the torch.

Checking your liner each time you change out your wire spool means you’ll be able to catch any problems with it early. A damaged or dirty liner is only going to cause wire feeding issues, so if it needs to be replaced, get a new one.

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They also protect your head and face from sparks and smoke. That’s why choosing a good helmet that’s going to offer the best protection is essential.

But what makes a welding helmet ‘good’? We’ve covered all the features you should be looking for in your next welding helmet.

Safety Standards

When looking for a welding helmet, the first thing you should check is the safety standards. If the helmet you’re looking to purchase doesn’t meet the regulations of your region, it’s not a good helmet.

In Australia, every welding helmet needs to meet the standards AS/NZS 1338.1 (auto-darkening) & AS/NZS 1337.1B (high impact). These standards ensure that the helmet can withstand high impacts without breaking and that all auto-darkening lenses provide 100% protection against harmful UV and infrared rays.

Note: The Aussie and Kiwi standards are not interchangeable with European ones, so make sure you purchase a helmet from a reputable brand that meets the local requirements for the safest weld.

Auto-Darkening vs Passive Helmet Lenses

What Is a Passive Helmet?

A passive lens welding helmet comes with a lens that uses UV and infrared coated glass that is tinted to a set shade, usually shade #10. These helmets don’t change shades, so they need to be flipped up when you’re not welding to be able to see.

That means when prepping the weld joint, positioning the torch or inspecting the weld, the helmet needs to be up. It can be flipped down by flicking or nodding your neck, allowing it to fall back into place so you can strike an arc.

There are a few problems associated with passive helmets.

First, it can be difficult to keep the torch perfectly lined up while getting the helmet back into place, especially if you’re still learning to weld.

Second, the shade can’t be changed. If you were to TIG weld at low range amps (50A), or MIG weld at 250A, the fixed shade of the helmet wouldn’t be suitable. You either wouldn’t be able to see the weld properly, or the weld would be too bright, which can still cause damage.

Third, the constant up and down of the helmet can put a serious strain on your neck. For any kind of tack welding or small sections, having to flip your helmet up every single time can really take its toll.

When you’re welding day in, and day out, that kind of stress on your neck can lead to injuries.

What Is an Auto-Darkening Helmet?

An auto-darkening helmet has a lens that tuns ‘on’ and ‘off’. When you’re not welding, and no arc is detected, the helmet’s lens will be shade #3 or #4 (depending on the brand).

This is quite a light shade, similar to looking through sunglasses. Once the sensors detect an arc, the lens will turn ‘on’, changing instantly (and automatically) to shade #9-#13.

There are two types of auto-darkening helmets available on the market: fixed or variable.

Fixed Auto-Darkening Helmets

A fixed auto-darkening helmet has a similar lens to a passive lens helmet. While it can change from light to dark, it only has one ‘dark’ shade, generally shade #10 or #11.

They remove the issue of neck fatigue and strain, as you won’t have to constantly take it off to check your weld, but they’re still not suitable if you’re welding at an amp range that isn’t covered by its pre-set shade.

Variable Auto-Darkening Helmets

A variable shade auto-darkening helmet, on the other hand, will change from light to different shades of dark. When an arc is struck, the lens will darken between shade #9 and #13. On high-end helmets, you can also select shades #5 to #8 for grinding, plasma cutting and low amperage TIG welding.

In general, UNIMIG recommends always getting a variable shade auto-darkening helmet. These days they can be bought on a budget, and you won’t have to worry about any accidental arc flashes.

If you’re going to get yourself a variable auto-darkening helmet, there are a few other things to consider.

Optical Clarity Classifications

What is the helmet’s optical clarity? The optical clarity is basically just how well you can see out of the helmet. Every auto-darkening helmet has four critical categories evaluated to determine its optical clarity. These tests are rated from 1 to 3, with 1 being the best and 3 being the worst. The four tests are:

Optical class: how distorted is the image through the lens? If you look through the lens, and it’s like looking through rippled water, then it’s not a good helmet. The image should be clear and crisp to obtain a 1 rating.

Diffusion of light class: are there impurities in the lens from the manufacturing process? These impurities make the lens unclear and hard to see out of, like fingerprints or scratches on glasses. The lens should be uniform and clear to obtain a 1 rating.

Variations in luminous transmittance class: focuses on the lens’s adjustable shade function. Once a shade has been selected, how consistent is it across the lens? A quality lens will be the same shade up or down, left to right, and in the corners. There should be no areas that are too bright or too dark, as this affects the optical clarity. An even shade across the entire lens is needed to obtain a 1 rating.

Angle dependence on luminous transmittance class: there should be a clear view with no stretching, dark areas, blurriness, or problems when looking at an angle. This is similar to variations in luminous transmittance. It measures the consistency of the shades across the lens but at an angle. It should look the same downwards or upwards as it does straight through to obtain a 1 rating.

When you’re looking for a helmet, you’ll want one that has a good score on these classifications. A 1/1/1/1 is the best classification a helmet can get.

Shade Range

What is the shade range of the helmet? The shade range is how light or dark the helmet filter can get. The higher the number, the darker the shade.

It’s important to find a balance between adequately protecting your eyes while still clearly seeing your workpiece.

Every variable auto-darkening helmet will have a dark shade range of #9-#13, which covers MIG, TIG and stick. You can also get helmets that come with the additional dark shade range of #5-#9. Almost every helmet’s light shade is a #3 or #4.  

How bright your arc is (how many amps you’re running on) will determine which shade you’ll need. The lower the amps, the lighter the shade will need to be.

For example, on a #9-#13 helmet, low amp TIG welding (10-25A) will not be possible. You’ll need a shade #5-#9 helmet for low amp TIG. There are recommended shades for each type of welding and the amps you’re welding at.

When you’re picking a shade, it’s better to start with a shade that is too dark and get lighter. You don’t want to choose a shade that is too light and flash yourself trying to find the right shade.

Lens Sensors & Reaction Time

How many arc sensors does the helmet have? Most helmets will have between two and four sensors on them. Entry and hobby level helmets will generally only have two, while industrial level helmets will have up to four.

These sensors are what detect the welding arc and trigger the darkening in the lens. The more sensors you have, the better the coverage, which can be needed for any out-of-position welding that might obstruct some.

How fast does the lens react? The lens reaction time or switching speed is how quickly the lens goes from light to dark when it detects the arc.

Most professional welding helmets should have a reaction time between 0.1ms (1/10,000 of a second) and 0.04ms (1/25,000 of a second). The actual reaction speed of the helmet may vary depending on the operating temperature.

View Size

How big is the lens? Being able to see what you’re doing while you’re welding is essential, so you’ll want a helmet with a lens that’s big enough.

The lens size you get will mainly come down to personal preference, but a bigger lens can be beneficial if you’re welding out-of-position.

Adjustable Settings

Depending on the helmet you get, they may have the ability to change the lenses sensitivity and delay times.

Sensitivity: how much light will trigger the lens to darken. You can choose how sensitive you want the helmet to be. If you’re welding with low amperages (and a duller arc) or doing a lot of outdoor welding, you’ll want a helmet that you can increase the sensitivity on.

Delay: how quickly the helmet goes from dark to light. A short delay means the lens will lighten quickly, while a long delay will mean the helmet stays dark for longer. An increased delay is used a lot with pulse welding, as you don’t want the helmet to lighten as the arc fades during the cycles. If you were doing a lot of tack welding, a short delay would be great.

True Colour Lens Technology

Does the helmet have true colour, or is it green? True colour means that more colours from the spectrum can pass through the lens (more reds and blues, less greens) for better optical clarity. It eliminates the green hue that is typical of some older welding helmets.

It makes it much easier to clearly see the weld at all stages of the process, and it reduces eye fatigue so that you can weld for longer periods.

The EliteVision technology in UNIMIG helmets allows for a true colour view.

Comfort & Fit

How comfortable is the helmet? When you’re welding, especially if it’s for long periods, comfort is essential. The harness on the helmet is what makes them comfortable. You can get 3-point or 4-point harnesses.

The more points of contact on the harness, the comfier it’s going to be. This is because each point of contact allows for adjusting so you can better fit the helmet to your head. They also help distribute the weight evenly, so it doesn’t strain your neck.

Batteries & Solar Charging

Is the helmet solar powered? Does it come with a replaceable battery?  

Every welding helmet on the market is solar powered. Because a welding arc produces UV rays (which is what the helmet is protecting you from), the helmet can charge at the same time as it’s being used.

For the most part, you never have to worry about them failing. You can also leave them in the sun if you want to.

Solar-powered helmets still include an internal battery (this is what’s being charged) which powers up the helmet, but they’re not removable or replaceable. So if the internal battery were to stop working or storing charge, the entire helmet would need to be replaced.

That’s why some helmets (usually mid-to-high-end) also come with a separate backup battery. It’ll kick in if your helmet does run out of power or the solar charging fails.

The backup battery will keep the lens darkened if you’re in the middle of a weld, rather than having it turn off and flash you unexpectedly. These batteries are also replaceable if the backups themselves run out.

Grind Mode

Does the helmet have a grind mode option? While grinding may not be as dangerous as welding, it still produces sparks that your eyes should be shielded from.

That’s why some helmets come with a grind mode. It can be external, on an adjustable knob, or internal as a pressable button. In both instances, selecting this mode will stop the helmet from auto-darkening, so when sparks start flying, the lens will remain in shade #4 or #5.

It stays light enough to see clearly, and your eyes and face remain protected from any stray sparks and debris.

Grind mode means you don’t have to take your helmet off and on over and over, especially if you have a lot of grinding to do before or after the weld.

Magnifying ‘Cheater’ Lens

Mag (or cheater) lenses let you zoom in and get a closer view of your weld. They insert over the lens inside the helmet and work the same way that a standard magnifying lens does.

They’re perfect for getting a better view of small joints, or if you can’t wear your glasses with your helmet, you can use a mag lens as an alternative.

Respirators and Other PPE

Can you fit other pieces of PPE under the helmet? A welding helmet isn’t always the only piece of PPE that you’ll need to protect your face with.

If the welding you’re doing is producing a lot of fumes, or your position means your face is trapped in them, you’ll need a respirator. Respirators will keep your lungs clear of any welding fumes and gas.

While welding helmets offer ample protection, it is still recommended that safety glasses be worn underneath for an extra layer of shielding for your eyes.

A lot of welding helmets sit flush against the face, making it impossible to wear respirators or safety glasses without the helmet sitting funny and exposing the front of your neck. If you’re planning to have any added protection, make sure it fits.

PAPR Helmets

Are you going to be welding in confined spaces or somewhere your face is stuck in welding fumes? If you’re exposed to welding fumes, especially for long periods of time, you should look at getting a PAPR helmet.

A Powered Air Purifying Respirator (PAPR) is a battery-powered, belt-mounted, portable respirator attached inside a sealed helmet.

It does all the work of keeping the welder supplied with fresh, clean air. It filters any welding fumes, gas or other particles out to keep you protected while you work. 

PAPR helmets come with an attached hood that slides over the head and can be sealed, so no external air can get in. It’s protective, comfortable, and maximises the effect of the filtered air. 

The powered respirator means you don’t have to try and fit a normal mask under your helmet as well. Instead, a breathing hose connects from the back of the helmet into the filter. The air is filtered and then sent up to the helmet, keeping the entire helmet filled with clean air. 

The UNIMIG PAPR helmet also comes with all the other features that make our helmets top of the line. You don’t have to sacrifice any of the other great features to stay safe.

UNIMIG Helmets

Every UNIMIG helmet is suitable for MIG, TIG, stick, plasma and grinding.

Each helmet comes with the following settings:

• Weld/Grind – weld mode or grind mode
• Shade – select the shade needed for your type of weld
• Sensitivity – how sensitive to the light your helmet is
• Delay – how quickly the helmet goes from dark to

Our entry-to-mid-level helmets come with an optical clarity rating of 1/1/1/2 and a shade range of #9-#13.

Our professional-grade helmets come with an optical clarity rating of 1/1/1/1 and a #5-#13 shade range. They also come with three memory profile buttons on the inside. No matter which helmet you get, just make sure that it’s going to protect your eyes no matter what kind of welding you have planned.

Check out the full range of UNIMIG Welding Helmets

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Changing the waveform affects the weld because different waveforms can change the arc’s characteristics, the bead profile, and the penetration of your weld. Before you go and pick up a new TIG welder, though, let’s cover what a waveform is and what they do.

What is a waveform?

Waveforms only apply to TIG welding and only to AC. DC TIG welding has no waveform, as the current only travels in one direction. DC either runs positive or negative, but not both.

On the other hand, AC alternates between the two. The way the current flows between the positive and negative polarities is known as the waveform.

Because waveforms are only relevant to AC welding, aluminium is the main application that you’re going to be working on when fiddling with these settings.

Sine waves

Sine waves are the original type of waveform. They’re the default (and only) waveform on old-style transformer machines, which were also only capable of running at 50-60Hz.

On the newer inverter machines, you can now choose whether you want to use a sine wave, and it’s no longer the default. Bonus, you can also change your AC frequency on the newer inverters.

The bell-shaped curve of this wave means that it has a smooth transition between the electrode positive (EP) and electrode negative (EN) polarities. The bell curve also means that only a short period of time is spent at the peak of the EP and EN, so there’s not a huge amount of heat being transferred into the metal.

Compared to the other waveforms, the sine wave is about the middle ground in terms of heat input. This could be an advantage or a disadvantage depending on what you’re doing.

Because of the limited amount of time spent at the peak, the output power is constantly (though quickly) fluctuating, so the arc is not the most stable. However, the smooth transition between EP and EN helps to provide good wetting in the toes of the weld.

Sine waves also have a softer, quieter sound than some of the other waveforms.

Using the sine wave on an inverter machine produces the same feeling as the old conventional machines.

These days most TIG machines use advanced square waves as the default waveform, including all UNIMIG TIG machines.

Advanced Square waves

The advanced square wave is just what it sounds like, with a square-shaped wave. Because of this, the max amount of time possible is spent in the peak of the electrode positive (EP) and electrode negative (EN), so it has a very high heat input.

The square shape also means that the switch between EP and EN is almost instantaneous, which gives it an incredibly stable arc.

The stable arc paired with a high heat transfer means that the advanced square wave provides deep penetration, faster travel speeds, and has a fast-freezing puddle.

It does, however, have quite a high pitched and harsh sound.

Soft Square waves

The soft square wave is like a blend between the square and sine waves. It still has the square shape, giving you the max amount of time at the peak of the electrode positive (EP) and electrode negative (EN). However, the slight curve means that the transition between the EP and EN is not as harsh, which gives it a softer arc than the advanced square.

A ‘softer’ arc means that the toes of the weld wet in better. The puddle is more fluid and doesn’t freeze as quickly, but you still have great arc stability and control. The softer arc also means it produces a softer sound.

Soft square waves still have a high heat input, but it’s slightly less than advanced square.

Note: Square waves were originally symmetrical, but with advances in technology, it is now possible to change the amount of time spent in the EN and EP portions of the cycle. This is known as the AC balance, which we’ve covered in-depth here.

Triangle waves

Like the square wave, the triangle wave is named after its shape. Because of its shape, the triangle waveform has some of the most unique features.

There is very little time spent at the peak of the electrode positive (EP) and the electrode negative (EN), but it has a very fast transition between them. The limited peak time and quick transition give it an incredibly stable arc with low heat input.

The low heat input of the triangle wave is what makes it the favourite waveform when it comes to welding thin metals, as it reduces the amount of distortion.

You may need to run the triangle waveform on higher amps than you otherwise would because of this lower heat input. However, once you’ve got the proper settings, it gives quick puddle formation, and you can travel along at a relatively fast speed.

Each waveform has its pros and cons, and which one you want to use will depend on the material thickness. The square waves will work well for most applications, but you can try them all out and see which one works the best for your weld.

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What is Stick (MMA) Welding?

Manual Metal Arc (MMA) welding is an arc welding process in which an arc is formed between a flux covered electrode and the base metal. The arc melts the electrode into the workpiece, forming the weld. 

MMA is also referred to as Shielded Metal Arc Welding (SMAW), but it’s most commonly known as ‘stick’ welding, after the stick like electrodes used for the weld.

How Does Stick Welding Work?

Stick welding is one of the simplest types of welding because it uses the least amount of equipment. It requires a completed electrical circuit to ignite an arc, which is formed by all the components of the welder.

First, an electrode holder is connected to the welder, and the electrode itself is inserted into the holder. An electrode holder is a much simpler ‘torch’ – its only purpose is to hold an electrode in place and allow the welding current to flow through it. There are no buttons or dials involved at all.

The electrode is tapped or struck against the base metal, which ignites the arc between the two. The electrodes used in stick welding are consumable electrodes, as they melt into the base metal to form the weld.

That’s the first half of the electric circuit done.

Unlike MIG or TIG, stick welding doesn’t need an external gas. Instead, the outer flux coating on each electrode works to shield the weld as it melts. The flux coating melts with the metal, releasing gases from within which bubble to the surface.

These internal gases protect the weld from outside contaminants until the puddle begins to cool. The flux coating, once melted, forms a layer of slag over the final weld, which needs to be chipped off to achieve a clean, finished weld.

The second half of the circuit is the earth clamp. If you don’t have your machine grounded, your electrode won’t arc. It needs to be attached to clean, bare metal, as a bad earth will give you issues (like a wandering arc) as well.

So, to complete the circuit, make sure you plug your clamp into the machine and connect it to a clean spot on the metal you’re welding.

Stick Electrode Selection

There is a range of different electrodes available for stick welding. Each is stamped with its own classification code, which details the properties of each electrode. For mild steel electrodes, there is an ‘E’ followed by a 4-digit code, for example, E6013.

Here’s a breakdown of what each part of the code means:

• The ‘E’ stands for electrode. Every mild steel electrode will start with E.
• The first two numbers (60) represent the tensile strength of the electrode after it’s welded. Pretty much every electrode available will be labelled 60 or 70, as a tensile strength of 60,000ksi to 70,000ksi will cover almost every metal.
• The third number (1) indicates the weld positions it can be used in. There are only three variations of this number: 1 (all positions), 2 (flat & horizontal) and 3 (flat only).
• The fourth number (3) refers to the type of flux coating. There are nine different types of flux coating, each with its own characteristics.

Generally speaking, the most common electrodes used for mild steel are E6010, E6011, E6013, E7016, E7018 and E7024. Stainless steel electrodes are marked with their metal grade, e.g., 309L.

When it comes to learning to stick weld, though, we’d recommend using E6013’s, as they’re considered general purpose, they work well on all applications, they’re all positional, and they’re easy to strike.

The electrode size you’ll need will depend on how thick for plate is. Generally speaking, a 2.5mm diameter electrode works for 3mm – 6mm, a 3.2mm electrode works for 6mm – 12mm, and a 4mm electrode works for 12mm – 25mm.

Settings

The best part about stick welding is that there’s only one setting: your amps.

What you want to set your amps to depends on a couple of things, including the electrode type and diameter, the base metal thickness, and your weld position.

Most electrode packets will come with a recommended range of amps that the electrode can handle/will melt at, so even if you’ve got no idea, they provide a good starting place. Starting in the middle of the recommended range and adjusting up or down as needed is usually the best way to find what’s going to work for you.

Polarity

Stick welding can be done in AC or DC.

For the most part, stick electrodes generally run on a positive polarity or Direct Current Electrode Positive (DCEP). That means the current is positively charged and runs from the negative to the positive.

In this case, the current runs from the base plate into the electrode. It sounds counterproductive, but the heated electrode then melts back into the plate, providing solid penetration.

Some electrodes are capable of being welded on negative polarity or Direct Current Electrode Negative (DCEN) as well. The current runs in the opposite direction, from the electrode into the plate, which gives shallower penetration than DCEP.

If you have an electrode that can be used on AC, you’ll find that the penetration of the weld falls between the two. It’s not as shallow as DCEN but not as deep as DCEP. That’s because the current alternates between the positive and negative polarities while it welds.

Each stick electrode will say whether they should be used in DCEP, DCEN or AC on their packaging.

To set up a UNIMIG welder for DCEP, plug the electrode holder cable into the positive (+) panel mount and the earth clamp into the negative (-) panel mount.

For DCEN, plug the electrode holder cable into the negative (-) panel mount and the earth clamp into the positive (+) panel mount.

You can only DC weld on our stick dedicated machines. So, if you have an electrode that can be used in AC and that’s how you want to weld it, you’ll need an AC/DC TIG machine that’s set up to stick weld.

To run an AC stick weld, you’ll set up your leads for DCEP. There is no specific ‘AC stick’ setting on most machines. Instead, you’ll need the AC version of the electrode you wish to weld.

Metals

Stick welding is the least versatile when it comes to how many different types of metal it can be used on. It can weld:

• Mild steel
• Stainless steel
• Cast iron

Common Stick Applications and Fabrications

Despite the limited range of metals it can weld, stick welding is still one of the most used welding processes used today.

Some common stick welding uses include:

• Construction and building – stick welding is the most used type of welding for major construction. Its ability to weld very thick metals with multiple passes make it ideal for major structural work.
• On-site and outdoor work – because it’s gas free (and stick dedicated machines are relatively small), it’s the first pick for outdoor work and on-site work thanks to its portability.
• General fabrication and repairs – while it can’t weld sheet metal, stick welding is still a sound choice for frames, fences, farm repairs, and other jobs.
• Pipe welding – gas pipes, power plant pipes, and any other kind of pipe welding generally favours stick, especially for a root run.
• Home hobby use and DIY projects – the simple setup and lower costs make stick welding a great choice for weekend warriors, plus they’re small, so they’re easy to store.
• Mining – with no gas needed, stick machines are the most portable, perfect for mining sites.
• Underwater – all underwater welding uses stick welding as it is the only process capable of being used in water.

Advantages of Stick  

There are plenty of reasons why stick is still so popular in the welding industry and why it won’t be going anywhere.

• It can be used anywhere. So long as you have access to a power supply, you can use your stick welder. They’re the most portable machine, thanks to not having to lug a gas bottle with you wherever you go.
• It’s easy to learn. The hardest part of stick welding is consistently striking an arc, the rest of the process is super simple, and it’s great as a starting point for welding.
• It’s perfect for outdoor use. Because it doesn’t use gas, you can work on any outdoor application without worrying about your shielding gas being blown away.
• It’s not fussy. While MIG and TIG require thorough cleaning of the base metal before it can be welded, stick welding will work on rust, millscale and other contaminants. However, this is only to a certain degree, and it’s still best practice to clean the metal anyway for the best possible weld.
• It’s affordable. Dedicated stick welders are the least expensive machines you can get at each amperage point, and the only extra you’ll need to get going is the electrodes.
• It can weld thicker. Stick machines can weld thicker materials and thicker electrodes than TIG at the same amperage.

Disadvantages of Stick

While it has its advantages, there are still a few reasons you wouldn’t pick stick.

• It’s slow. The travel speed with a stick electrode, paired with the need to grab a new one each time it runs out, adds up, making it a time-consuming way to weld.
• It’s messy. Stick welding produces a lot of spatter and smoke, much more than TIG or MIG does. Plus, some electrodes are more aggressive, creating more spatter.
• There’s extra downtime. Once you’re done with the weld, you’ve still got a bit of extra work before the job is done removing slag from each weld. Depending on the electrode you’re using, this can be easy, or it can be a bit of a challenge.
• It’s not as versatile. It can’t weld as many metal types as MIG or TIG, so the number of applications it can be used for is limited.
• It can’t weld thin metal. It can’t weld thinner than 2mm metal. If you want to attempt it, you can try DCEN to reduce penetration in the weld, minimising burn through.

If you want to get into welding, stick welding is a great, cost-effective way to learn how to weld, and it’s a skill that can be used across a range of applications.

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Learning how to TIG weld does take a lot of practice, and the need for both hands makes it more difficult than MIG or stick. But that doesn’t mean it’s an impossible task that you shouldn’t even think about until you’ve mastered everything else.

TIG welding is like any other kind of welding. You should start with the basics.  

What is TIG Welding?

Tungsten Inert Gas (TIG) welding is an arc welding process in which an arc is formed between a non-consumable tungsten electrode and the workpiece to create the weld.

Filler metal is added manually, though it isn’t always necessary.

An inert shielding gas is fed through the TIG torch to protect the weld from outside contaminants.

TIG welding is also known as Gas Tungsten Arc Welding (GTAW).

How Does TIG Welding Work?

You can TIG weld two different ways: with alternating current (AC) or direct current (DC). Either way, it needs a completed electric circuit running on a constant-current power source to work. All the parts of a TIG machine work together to form this circuit.

First, the TIG torch is assembled. The collet, collet body/gas lens and back cap all slot together to hold the tungsten in place in the centre. A gas shroud goes over the top to direct the shielding gas.

The TIG torch plugs into the welder, forming one part of the welding circuit. An arc is formed between the tungsten electrode and the workpiece.

Tungsten has a melting point of 3,422°C, so it can withstand the heat of a welding arc. That’s why it is a ‘non-consumable’ electrode. It doesn’t melt and enter the weld pool.

To add metal, an additional filler rod can be fed into the weld puddle by hand to form a proper weld.

That’s half of the electric circuit.

To complete the circuit, an earth clamp is needed. If you don’t have an earth clamp plugged into the machine and connected to the metal you’re trying to weld, the welder won’t even arc.

The ground also needs to be attached to clean, bare metal to work properly. Having a bad grounding will cause issues with the arc and it can become unstable or start to wander.

TIG welding is the only welding process that requires the use of both hands to create the weld, so it has a steeper learning curve than MIG or stick.

Tungsten Electrode Selection

There are a number of different tungsten electrodes, each with its own unique qualities.

The tungsten you’ll need will depend on two things. Whether you’re welding on AC or DC and the metal you’re welding. (A bit of personal preference might also come into play.)

Check out our TIG Tungsten Selection Guide for a full breakdown of each tungsten, including pros, cons, and the distinct features of each. It’ll help you work out which tungsten is perfect for your next TIG weld.

Shielding Gas

Choosing a shielding gas for TIG is actually quite easy. The choices are pure argon, argon, and… argon.

Okay, that’s not entirely true. You can use any inert (noble) gas there is. Out of the six, four of them aren’t financially feasible. That leaves argon and helium.

TIG welding is sometimes referred to as “Heliarc” when helium gas is used. However, helium is expensive, so straight argon is the most common gas used – and it works with every kind of metal.

If you do want to know more, we’ve got an article on which gases you can use and why.

Metals

TIG welding is the most versatile when it comes to the number of materials it can weld. It can be used to weld:

• Mild steel
• Stainless steel
• Aluminium
• Copper
• Bronze
• Zinc alloys
• Titanium

Aluminium can only be welded on AC, so if you’re welding aluminium, make sure you have an AC machine such as the RAZOR TIG 200 AC/DC. Some machines, like the VIPER 185, are DC only.

Your filler metal needs to match the metal grade you’re welding, so if you’re welding 316 stainless steel, make sure you’ve got 316 stainless filler rods.

The filler rod should also be the same diameter thickness as your tungsten. For example, if you’re welding with a 1.6mm tungsten, you’ll need 1.6mm filler rods.

Polarity

So long as you have a welder that is capable, you can TIG weld in AC or DC.

Regardless of which way you want to TIG weld, it’ll be done in negative polarity or Direct Current Electrode Negative (DCEN). That means the current is negatively charged and runs from the positive to the negative.

To set up a UNIMIG welder for DCEN, plug your torch into the negative (-) panel mount and your earth clamp into the positive (+) panel mount.

If you have an AC capable welder, you should be able to select it using the machine’s settings without changing the polarity.

Common TIG Applications and Fabrications

Despite the learning curve, TIG welding is incredibly popular thanks to its range of metal types and weld appearance.

TIG is most commonly used for:

• Thin metals – sheet metals, car panels, exhaust pipes. You name it, TIG is the best way to weld it. With the lower heat outputs, it’s perfect for welding super thin materials without the risk of burning through.
• Precision welds – The sharpened tip of a tungsten means that most TIG weld pools are smaller than MIG or stick. A smaller puddle gives the operator more control and a more precise weld, perfect for things like thin outside corner joints.
• Aluminium – TIG welding is considered the best way to weld aluminium, thanks to the cleaning properties that come with AC.
• Art – A professional TIG weld looks like a stack of dimes, making it the most aesthetically pleasing weld. Sculptures, pictures drawn by welding, coloured welds, etc., are all best done with TIG.
• Home hobby use and DIY projects – it may be the hardest to learn, but TIG welding can still be used for your DIY home projects. Bikes, trays, shelving, even the restoration project on that old car you’ve been putting off forever. 
• Industries like construction, automotive, even aerospace – TIG can cover a full range of metals, it can weld thinner than MIG or stick, and filler is optional. As a result, it can be used for so many different projects: aeroplanes, nuclear plants, car parts and repairs, pipe welds.  

Advantages of TIG

There are lots of reasons why TIG welding is used as often as it is, not just because it looks the best.

• It creates strong, aesthetically pleasing, quality welds. TIG welds are high quality, they look great when they’re done, and they’re just as strong as any other kind of weld.
• It’s versatile. TIG works on a huge range of different metal types (ferrous, non-ferrous, specialty) and metal thicknesses. You can also choose whether or not to use filler metal as well.
• It welds in every position. TIG welding works regardless of whether you’re in a flat, horizontal, vertical, or overhead position.
• It can weld at low amps. TIG’s ability to weld well at low amps makes it ideal for very thin applications like sheet metal or any precision welding where control is critical.
• It’s easy to see. The arc often isn’t as bright (if you’re on low amps), plus TIG torches come with additional accessories like quartz cups that make seeing your weld easy.
• It doesn’t produce spatter or slag. TIG welding is the cleanest way to weld, as it doesn’t produce any spatter or slag, plus there’s minimal smoke too. Sometimes you don’t even need to clean post-weld at all.
• It only uses one gas. TIG welding only runs with pure argon gas, so you don’t have to swap when changing metals.
• It allows for total control. The number of adjustable settings and the ability to change the amps via a foot pedal or potentiometer during the weld means you have complete control over any weld.

Disadvantages of TIG

Even though it has a laundry list of uses, TIG isn’t always the most feasible option, and there are a few downsides as well.

• It’s slow. TIG welding is the most time-consuming way to weld. Hand feeding the filler rod means it takes longer than MIG or stick.
• It takes a lot of practice. It’s well known for being the hardest kind of welding to learn, mainly because of the coordination between moving the torch and feeding the rod in at the same time.
• It’s not great for thick metals. While TIG is great for sheet metal and other thin pieces, it’s not recommended for thicker welds. For example, a 200 amp TIG machine generally caps at a maximum of 8mm, whereas MIG and stick can both usually weld up to 12mm at the same amperage/current.
• Everything has to be squeaky clean. TIG is the least forgiving when it comes to metal cleanliness. There can’t be any rust, paint, oil, dirt, etc., or you’ll end up with defects. Give your metal a wipe down or wire brush it before you start to make sure it’s good to go.

It might take some time and practice to start with, but TIG welding isn’t a skill that needs to be avoided, even if you are just starting out with welding.

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What is MIG Welding?

Metal Inert Gas (MIG) welding is an arc welding process in which a solid wire electrode is continuously fed through a welding gun into a weld pool. An arc is formed between the wire electrode and base metal, melting the base material while consumable filler wire is deposited, creating the weld.

At the same time, a shielding gas is fed through the welding torch to protect the weld from outside contaminants.  

MIG welding is also known as Gas Metal Arc Welding (GMAW).

How Does MIG Welding Work?

The MIG welding process is relatively straightforward, and most of it is automated too.

MIG welding is always done on direct current (DC), which means that the current only runs in one direction. Like a battery, it requires a completed electrical circuit to work. All the components of the welder work together to form this circuit.

First, a wire spool is loaded into the machine. This wire is fed through the driver rollers, into the torch liner and out of the contact tip and nozzle. The wire will start feeding continuously when the torch trigger/button is pressed and stop when it’s released.

Pressing the torch trigger will also start the gas (if it’s needed), which is fed through the nozzle to shield the weld.

The wire plays two parts: heat source and the filler material. When the wire passes through the copper contact tip, it becomes electrically charged with the welding current. The wire comes out of the torch and touches the base metal, creating an arc between the two.

That’s the first half of the electric circuit formed.

The arc melts both metals, depositing filler metal into the molten base metal to form a weld. There are several ways filler metal can be transferred from the torch into the base. Your normal MIG welding transfers metal via the short circuit mode.

Check out our post on short circuit welding and the other modes of metal transfer to learn more.

The final piece of the puzzle is the earth clamp. Without it, your machine won’t arc. You can still pull the trigger and feed the wire through your torch, but all you’ll end up with is wasted wire.

The earth clamp completes the electric circuit that runs from the machine, through the torch, into the base metal, and then back up the earth clamp to the machine.

On top of that, getting a proper grounding is important because a bad earth can cause several issues, including burnback and a wandering arc.

MIG welding is considered a semi-automatic process. The wire feeding is automatic, but the torch movement is still manual, making it semi-auto.

Settings (Voltage & Wire Feed Speed)

There are only two settings on MIG dedicated machines: voltage and wire feed speed.

The voltage determines how much heat is in the weld. Turning it up or down will adjust how much welding current is added to the weld.

The wire feed speed determines how much wire per minute is added to the weld. The more wire that’s added, the cooler the weld will be, and vice versa.

Your voltage and wire feed speed generally work in harmony together. If you turn your wire feeding to the max but leave your volts too low, the wire won’t burn. You need enough heat to melt the wire, but not so much heat that it gets sprayed everywhere except in the weld.

What you want to set them to depends on a few things. The metal thickness, the metal type, filler wire thickness, weld position and joint type will all impact the settings.

If you’re not sure where to start, almost every UNIMIG MIG welder comes with a Setup Guide on the inside of the machine’s door. It provides recommended settings for different metal types, metal thicknesses and wire sizes as a starting point. It also includes the gas flow and polarity recommended for each application.

Polarity

Getting the polarity right is pretty important, as it impacts the quality of the weld. The wrong polarity will leave you with excessive spatter, an uncontrollable arc and poor penetration.

Gas MIG welding runs on an electrode positive polarity. That means the current is positively charged and runs from the negative to the positive. It’s most commonly referred to as reverse polarity or DCEP (Direct Current Electrode Positive).

To set up a UNIMIG welder for DCEP, plug the polarity cable in the positive (+) panel mount and the earth clamp into the negative (-) panel mount.

In our case, the polarity cable acts as the torch because all of our MIG torches come with a Euro quick-connect plug. If your machine doesn’t have a Euro connection, it’ll plug directly into the dinse connecter.

Keep in mind, only gas MIG uses DCEP. The polarity is flipped to DCEN (Direct Current Electrode Negative) if you’re looking to weld with flux-cored (gasless) MIG wire.

That means you’ll plug your torch/polarity cable into the negative (-) panel mount and your earth clamp into the positive (+) panel mount.

Metals

MIG welding is one of the more versatile when it comes to the different materials that it can be used on. These metals include:

• Mild steel
• Stainless steel
• Aluminium
• Copper
• Bronze

Wire Electrode Selection

There are two things to consider when picking your filler wire. Making sure the base and filler metals match and getting the right size.

You want your wire metal and its grade to be as close a match to your parent metal as possible. If you’re welding with mild steel, you’ll need mild steel wire. If you were welding aluminium, you could choose 5356 or 4043 or another grade wire, depending on your parent metal.

Filler wires of the same metal as your base metal will work even if the grades aren’t an exact match. Don’t worry if you’re not sure what grade your metal is; just match the metals.

The other thing to consider is how thick your wire is. If you’re working with sheet metal, you’re not going to want filler wire that’s 1mm thick. Your wire should be thin enough that it’ll melt but thick enough that there’s enough metal deposited to form a proper join.

A good all-around wire size is 0.8mm. You can drop down to 0.6mm for very thin metal or go up to 0.9mm for thicker applications.

Shielding Gas

Shielding gas is used to protect the weld from outside contaminants. The gas you can use will vary depending on the type of metal you’re welding. Different gases also have different effects on the weld.

The most common (and generally best) shielding gas you can use for mild and stainless steel is a 75% argon/25% CO2 mix. It helps stabilise the arc and deepen penetration while shielding the weld. For aluminium welding, pure argon gas is needed for shielding.

These aren’t the only two that are available, though. For a full list of all the different gases you can use, check out our post on choosing a MIG gas.

Common MIG Fabrications and Applications

MIG welding can be used on a wide range of metals across a wide range of thicknesses. It’s also one of the fastest ways to weld. These factors combined make it the most commonly used welding method across several industries.

Some of the most common uses of MIG include:

• Home hobby use and DIY projects – the relative ease of MIG welding makes it a perfect option for first-time welders and weekend warriors
• Automotive repairs – MIG’s ability to weld sheet metal at speed makes it a preferred method for car repairs, as it’s a faster option than TIG
• Farm repairs and outdoor use – the gasless MIG option (otherwise called FCAW) means it’s practical for the outdoors and other off-grid applications
• General fabrication – frames, trailers, etc. are usually done with MIG
• Construction – its speed, ability to weld relatively thick metal (16mm @ 350A) and minimal clean up (compared to stick welding) makes it a time and money saver across construction applications

Advantages of MIG

There are a lot of things that make MIG a great choice, not just the fact that it’s easy to learn (though that is one of them!).

• It’s versatile. MIG welding can be used on a wide variety of metal types and thicknesses, covering most welding applications.
• It’s more efficient, with higher productivity compared to other methods. Because MIG wire comes in large spools (1kg, 2kg, 5kg & 15kg), there’s less downtime than if you were swapping rods or chipping off slag. It also has a higher deposition rate, and there’s no electrode stub loss.
• It’s fast. On top of not needing to constantly replace your filler, MIG welding is the fastest type of welding.
• It’s easy to learn. Being a semi-automatic, point-and-weld process with two settings makes it the best type of welding to learn as a beginner.
• It welds in every position. MIG welding works regardless of whether you’re in a flat, horizontal, vertical, or overhead position.
• It’s relatively clean. Okay, so it’s not as clean as TIG welding, but MIG still produces minimal spatter, and there’s no slag involved at all, saving you time and effort.
• It produces aesthetic, high-quality welds. The ease of use, automatic wire feeding, and clear visibility of the weld pool means producing a good weld is easy.

Disadvantages of MIG

While it might be the most popular type of welding, that doesn’t mean there aren’t a few downsides to MIG.

• The initial cost. When first purchasing a MIG welder, the cost of the machine, gas, filler wire and other consumables can add up. It’s not as cheap to get going with MIG as it is with stick. The good news is that your MIG machine should last you years.
• It’s not suited for the outdoors. Any kind of wind or breeze will blow your shielding gas away, leaving your weld exposed to contaminants. However, there are some solutions, like setting up welding curtains or other barriers. You could also swap to gasless MIG.
• It’s not very portable. The fact that you need a bottle of gas means that moving the welder around frequently isn’t the easiest task.
• It can’t weld through dirt and rust. Your base metal will need to be clean before it can be welded on. This is true of most welding, though there are more forgiving weld methods than MIG in this regard.

In summary, MIG welding is fast, efficient, simple to set up, easy to learn and used for almost everything. If you’re just getting into the world of welding, it’s the perfect place to start.

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Starting from inside the machine and working our way through to the torch, here’s how to troubleshoot every potential issue you might face.

Have you got good quality wire?

The first thing that goes into your MIG welder is the spool of wire. The actual quality of the wire can make a difference to how smoothly it feeds. Make sure to get good quality MIG wire that meets the Australian and New Zealand standards at a minimum.

You’ll also want a wire spool that’s been precision wound by a machine, which these days they mostly are. If you open up your spool and it looks like it’s been randomly wound with wires overlapping all over, it’s not going to feed well. Good quality MIG wire is precision wound for the smoothest possible feeding.

If your MIG wire spool has been sitting in the garage for a while, you should check that it’s still okay to use. If it wasn’t sealed before it was put away, moisture and prolonged exposure to the air might have caused it to rust.

Running rust through your torch liner will cause even more issues, so it’s best to avoid it entirely. If you do see rust on your spool, there’s a good chance that rust goes all the way through, and you’ll need to get a new one.

When you’re done with a roll of MIG wire, place it in a plastic bag or wrap it up in some cloth. Anything that helps keep moisture and air out, so you can get the most from it for future uses.

Is the spool loaded in properly?

The nut used to secure the spool in place is called a ‘spool retaining nut’, and it is there to hold the spool in place and keep it from free spinning.

If the nut isn’t tight enough, the spool will spin freely and potentially come loose from the spool holder, leaving you with a mess of wire.

Your spool should be hand tightened and not loose at all to ensure that it spins properly and brakes.

You should also check that the spool is lined up with the alignment knob on the spool holder. If it’s out of alignment, the spool won’t brake properly when the trigger is released, and your wire will come loose.

Check the wire feeding unit itself

The feeder relay unit, more commonly known as the unit powering the drive rollers or wire feeding unit, might be faulty. If this is the case, unfortunately, there’s not much you can do to fix this yourself.

If the wire doesn’t feed at all, or it shudders and feeds erratically, there’s a chance it’s your feeder unit. If your feeder relay is the problem, you’ll need to take your machine in for a service.

Drive rollers

There are a couple of things that need to be checked when it comes to the rollers.

First, make sure you’re using the correct drive roller for your metal type. V groove rollers are needed for mild and stainless steel wires. F (flux) or K (knurled) groove rollers are required for gasless flux-cored wires. U groove rollers are needed for aluminium.

Second, make sure the roller is the right size. Your roller and wire should be the same size so that the roller can properly grip the wire, but it’s not squished in. For example, if you’re welding with 0.9mm wire, your roller should also be labelled 0.9mm.

Most drive rollers come with two sizes on the one roller, so you could have a roller labelled 0.8 on one side and 0.9 on the other. These labels usually correspond with the groove closest to it, so just check that you’re loading the roller into the machine the right way.

Third, make sure that the tension is correct. The drive rollers have a tension adjustment knob, which doubles as the locking mechanism for the rollers. If there isn’t enough tension on the rollers, the wire will slip. If there’s too much tension, it can cause deformities in or flatten the wire.

You can check you have the right amount of tension by feeding the wire through your fingers (while wearing gloves). Grip the wire lightly, and if the wire feeds smoothly without being stopped or slipping, it’s the right amount of tension.

Keep in mind that the grooves in driver rollers can wear down over time and lose their shape, so they’ll need to be replaced every now and then.

Lastly, make sure your rollers are actually spinning. If the drive rollers aren’t rolling at all, it’s a more serious issue. An electrical continuity failure in the machine is the main reason your rollers would stop working.

If there’s a failure with your electrical components, you’ll need to take your machine in for a service.

Liner

Like your drive rollers, you’ll need to check that your liner is the right type and size.

Your liner size should be able to accommodate the size of your wire. Torch liners are colour coded, so you can tell on sight whether it’s the right one.

These liners are all designed for both gas and flux-cored steels. For aluminium, you’ll need the Teflon version of these liners. The different material is designed to make wire feeding softer metals easier. They also have a neck spring that the steel liners don’t, so it’s easy to tell them apart.

If you’ve got the right liner type and size, the last thing to check is that it’s fitted properly and it’s not blocked.

Over time, bits of wire debris can build up inside the torch liner, narrowing the hole and making it harder for the wire to feed. You can blow some of it out, but generally, you should replace your liner if it’s full of gunk.

Quick tip: Swapping your liner to a Teflon one when welding with aluminium means you won’t be feeding your temperamental aluminium wire through steel shavings. (Saving you from dealing with issues caused by contaminated aluminium.)

If your liner is still clean, check that it fits in the torch properly and it’s been cut to the correct length. There shouldn’t be any overhang, but if it’s too short, that can also cause wire feeding issues.

Finally, make sure the liner hasn’t been kinked. Even if your torch is straight, your liner might still have kinks from previously being bent. These small kinks can affect how well the wire feeds, so if you can’t straighten them out, you’ll need to get a new liner.

Contact tip

Your contact tips are pretty similar to the torch liners.

There are aluminium specific contact tips available, so make sure you haven’t accidentally left your steel tip on for an aluminium wire (and vice versa).

They’re also sized, so you can match them to your wire size. The contact tip size dictates how wide the borehole is, so a tip that’s too small won’t allow the wire to even feed through.

On the other hand, too big a contact tip means the wire won’t make contact, and it won’t become electrically charged, so an arc won’t ignite.

Quick tip: Take your contact tip off when you feed a spool through your torch for the first time. The wire might catch even if it’s the right size, leaving you with a birdsnest while trying to set up. You can slip the tip back on over the wire once it’s through the torch.

Contact tips wear down, and you can’t use the same one your machine came with forever. If your tip is visibly worn or damaged (e.g., from wire burning back), you’ll need to replace it.

They can also become blocked, which you can clear out. If it can’t be cleared, chuck it out and grab a fresh one.

Torch leads & trigger

If your wire isn’t feeding at all, check to see if your torch trigger is working. Use the wire feed button that’s usually found inside the machine to feed your wire through the torch lead. If that works, your trigger is likely broken and will need replacing.

The other reason your wire might not feed is because of a broken control lead inside the torch. If this is the case, you’ll also need to replace the torch.

Some other things that can cause issues with your wire feeding are the torch length and how straight it is.

The longer your torch is, the harder the driver rollers have to work to feed wire to the end. This is especially true of softer metals like aluminium, which are already difficult.

The average torch length is 4m, but if your wire is really struggling, dropping down to a 3m torch could make a real difference.

It’s also a good idea to try and keep the torch as straight as possible. Putting tight curls or having the torch lead double back on itself might kink your liner (see above), which will cause problems. It doesn’t have to be dead straight, but keep any loops in the torch as loose as possible.

If you’re really struggling, especially with softer wires like aluminium, you should try a push-pull gun. They come with a small motor in the torch itself, so the wire isn’t just being pushed the whole way; it’s being pulled through the torch as well.

Not every machine is compatible with a push-pull gun, as they don’t all have the right connection, but if it does, they’re a great option.

Other things to check

Here are a couple of other things you can check if you’ve tried everything mentioned above and you’re still experiencing issues with your wire feeding.

• Earth clamp – make sure the lead is plugged in and connected to the workpiece or close by on a metal table that the workpiece is touching. A bad ground can cause an erratic arc and wire feeding problems.
• Polarity – check that your earth and torch are plugged into the correct panel mounts for the metal you’re welding. If you’re unsure which polarity is correct, check out our Ultimate Guide.
• How long your torch is – when welding thin gauge wires like 0.6mm, a shorter torch is best. A 3m torch will mean the wire doesn’t have as far to travel, so it won’t have space to kink (as much as a 4m torch).

When it comes to wire feeding issues, there are a lot of steps you can take to try and fix the problem and get the machine back to running smoothly. However, if none of the above solutions work, your next step should be taking your machine in to get it serviced.

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Are you looking for a new, fun way to display your wine bottles? Don’t want to spend a fortune on something you could easily make yourself?

Well, why not have a crack at your very own DIY wine holder? Not only is it super simple, but rather than spending $50, you could save and spend just the cost of the metal (which cost us about $15)!

What You’ll Need

Metal

• 40mm x 3mm mild steel flat bar (you’ll need 5x 120mm pieces)
• 48mm (OD) x 42mm (ID) mild steel pipe, cut to 75mm long

Tools

• Combination square
• Half round file
• Angle grinder
• Chalk 
• Rule
• A piece of packing strap or similar
• (optional) Spray paint

STEP 1

Measure your flat bar. If you’ve got yourself one long strip of metal as we did, you’ll need to measure out five 120mm pieces with your chalk. 

STEP 2

Cut the metal where you’ve marked your five lines, using your angle grinder. 

STEP 3

Measure out your cross angles. Now that you have five strips of equally sized metal, you can go ahead and mark out the required angles needed to make the pieces fit together later. Because of the way the base plate is shaped, they don’t all get the same angles. 

On two of your pieces, measure a 45° angle from the corner on both sides. 

On two of your pieces, measure a 45° angle from one corner. On the other side, measure 20mm from the edge on your plate. Then, draw a line from that mark to the corner. 

On your last piece, measure two 45° angles. These two lines should be parallel to each other, as this will be your upright piece. 

Your angles should look like this:

STEP 4

Once everything is marked, cut out your angles. We recommend placing the metal pieces in a vice while you cut them with the grinder. 

STEP 5

Next is the pipe. Set your combination square to 75mm and mark from the end of the pipe. With your initial mark made, grab your piece of packing strap and wrap it around the pipe. You can trace along the edge of it to get a perfect circle all the way around. 

STEP 6

Cut your pipe to size. 

If your piece of pipe is already 75mm, you can skip these two steps. 

STEP 7

Clean up your bits of metal. Once your pipe and flat bar have been cut to size, make sure to clean off any burs with a grinder and flap disk. To get any burs that are on the inside of the pipe, grab your half round file and run it around the edge. You want everything to be smooth. 

STEP 8

Now for the exciting part: the welding. 

We used the RAZOR 200 AC/DC welder with the following settings:

• Set: DC
• Trigger: 4T
• Tungsten: 2.4mm
• Pre-gas: 0.2
• Start amps: 80
• Up slope: 0.2
• Peak amps: 90
• Down slope: 0.2
• Finish amps: 80
• Post-gas: 0.5

First, tack together your four base plates, making sure that everything lines up properly.

The two pieces with outward-facing 45° angles will fit together at the top. The two smaller angles, which you measured 20mm into the plate on, will then join to the bottom of those, creating a diamond with an open end. 

It should look like this when done correctly:

When they’re all lined up and tacked, you can weld them together. Once you’ve finished all your welds, sand them flush using a flap disk. For a sleeker look, you can round off the corners of your base plate as well. 

STEP 9

With your base plate finished, move on to the upright piece. Your base plate should have an open end and a closed end. You want to tack your upright piece in the middle of your closed end. You can line it up against the weld holding the two base pieces together. 

When you’re tacking this piece, make sure that it points outward, in the opposite direction of the open side of the base. It should look like it hangs over the outer edge. You can use a 90° magnet to hold it up while you tack it. 

STEP 10 

With your upright piece tacked, move on to marking a line along the axis of your pipe. You can do this in any way, but we’ve used a piece of angle that fit snug around the pipe to keep our line straight. 

STEP 11

Tack the pipe to your upright piece. You only want to have these tacked first to make sure everything lines up. It’s a lot easier to snap tacks than it is to get rid of a full weld if one of the parts goes wonky. 

STEP 12

Weld the upright piece and pipe together. When they’re done, give them a clean with your wire brush, and if you want, hit them with the flap disk as well.

STEP 13 (optional) 

Your gravity defying wine bottle holder is now done! But, you don’t have to leave it as is. If you want to, grab yourself some spray paint (we used semi-gloss black with primer) and give it a few coats. 

Now you can impress all your future guests with your welding skills and the wine holder.

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Do you need a new firewood rack for your home? Whether it’s for a fireplace inside or the firepit you’ve got in your backyard, you’ll need somewhere to store the wood.

A quick Google search will tell you that firewood racks are expensive. Unless you’re getting yourself a tote bag, most of them are going to cost you more than $100. (Not to mention the ‘honeycomb’ wood holder that was $750. Crazy.) 

Instead, why not save yourself some money, put your DIY skills to the test, and make your own! We’ve got a super easy to follow step-by-step guide on how to make your own firewood rack at home. The best part? Our full size, two-section rack cost less than $50.

What You’ll Need

Metal

• 25mm x 25mm x 2mm mild steel square hollow section (you’ll need 4x 1200mm pieces and 4x 300mm pieces)
• 400mm x 400mm x 6mm mild steel base plate 
• 25mm x 25mm x 2mm mild steel flat bar (you’ll need 4 pieces) 
• (optional) Caster wheels

Tools

• Angle grinder
• (optional) Drop saw
• Orbital sander
• Chalk 
• Measuring tape
• Combination square 
• Rule 
• Right angle magnet
• Clamps 
• Degreaser 
• Spray paint

STEP 1

Measure and cut your square hollow sections to the required lengths. You’ll need four sections cut to 1200mm in length and another four sections cut to 300mm in length. Make sure when you’re purchasing your metal that the bars are long enough; a 1m bar is going to be too short. 

Use your chalk, measuring tape and combination square to mark out the needed lengths along the bar.

STEP 2

Cut your bars. We used a drop saw to do this, but you can also use an angle grinder.

STEP 3

Tidy your metal pieces up. Once the bars are cut, take a grinder and flap disk to the edges to clean them up, smooth them out and make sure there aren’t any burs. 

Do the same for your base plate. Run your flap disk over the edges to get rid of any burs. You can also round out the corners of the plate to take the sharp edge off (it’ll hurt less when you accidentally walk into it). 

STEP 4

Measure and mark the base plate. Now that everything is smooth, take your chalk and combination square to mark 25mm in from each end of the plate, then use your ruler to draw the lines in. You should have a nice white chalk square on your plate when you’re done. This is so that you can locate the frame. 

STEP 5

Mark out 300mm at the bottom of the 1200mm pieces of square section. This will give you the cross-bracing locations (where you’ll weld your 300mm length pieces) and serve as a separator between the firewood and kindling parts of the rack. 

STEP 6 

Now for the exciting part: the welding. 

We used the MIG process on our VIPER 185, but you can weld this project together with any method. 

Note: If you’re welding dissimilar metal thicknesses, your machine settings should be for the thicker metal. If you’re using a UNIMIG MIG machine, you can find all of these recommended settings inside the machine’s door. You can learn more about welding dissimilar thicknesses here.

To weld these together, we’re going to make two H pieces. Grab two of your 1200mm bars and one of 300mm bars. Place the 300mm bar between the two where you marked out the 300mm line on the 1200mm piece so that you now have an H in front of you.

To make sure everything is squared up, measure diagonally from the top to the bottom of the 1200mm pieces. Both lengths should be the same. 

Keep everything in place with a few magnetic right angle clamps and tack the bars together. 

Quick tip: When you tack the 300mm bar in, only make a tack on the bottom to start with. Once it’s got the first tack, you can check to make sure your bars are still square. If they’re not, you can snap the tacks off or hammer the bars around a bit and square them back up. 

STEP 7 

Weld your bars together. When everything is tacked and squared, grab another of your 300mm bars and place it at the top. You should now have a rectangle with some overhang at the top and bottom.

DON’T weld this piece; simply clamp it in place. This will hold your frame still, and the bars won’t be able to bend in or out as much as you fully weld the bottom bars together. 

Now you can weld your H frame. Make sure you weld all four sides of the 300mm bar onto the 1200mm bar.

You can unclamp the top 300mm bar once your H is welded together. 

Do steps 6 and 7 twice. 

STEP 8

Sand your welds flush. It won’t matter so much for the welds that face up and down (the fillet welds), but sanding the two outside welds (the butt welds) flush with the bar will make the firewood rack look better, and it’ll make your next step easier. 

STEP 9 

You should now have two H shaped frames.

Next, you need to add the cross-sections. With your previous welds sanded flat, your remaining two 300mm bars will line up flush, which is what you want. 

Stand your frames up, clamp your cross-sections in place and tack them together. Don’t forget to check your diagonals before and after you tack them in. 

STEP 10

Weld everything together. It’s a good idea to start with the butt welds, check the diagonals, and then do the fillet welds. This will ensure that your frame will still be square once it’s all welded together. 

When you’re done, you can repeat step 8 and sand all your butt welds flush. 

STEP 11

Attach the frame to the base plate. Line the corners of the frame up with the corners on the base plate, using the markings you drew earlier. Once it’s lined up, you can tack it on.

STEP 12

Weld the frame onto the base plate. After you’ve tacked it, give the frame another check to see that it’s still square, and then weld all four sides of the bar onto the base.

Sand your welds flush once they’re done.

STEP 13

Now to make your end caps. The firewood rack still looks unfinished, with the open-ended tops, so let’s fix that. 

Here’s where the 2mm flat bar comes in. Using your combination square and chalk, measure out 25mm x 25mm four times, and cut out some end caps. 

Once they’re cut out, you can tack and then weld them into place, sanding the welds to smooth them out when done. 

STEP 14 (optional)

Add some caster wheels to the bottom. If you’ve got a set space that you’re going to put the rack, and it’s never going to move again, then you probably don’t need to worry about this step. But, if you’d like to be able to easily roll it around, even after it’s full of wood, you can weld on some wheels. 

Line the corner of the wheel’s plate up with the corner of the base plate. Tack it on through the holes. If your wheel’s plate doesn’t have holes, just tack around the edge. Clean the welds up with your flap disk, and now you’re ready for paint. 

STEP 15 

Now that your firewood rack is fully assembled and welded, give it a once over with an orbital sander.

If you’re happy with the rustic, bare metal look, you can go ahead and call it a day here. You now have a completed firewood rack! 

If you’re like us, and you like to finish things off with a nice coat of paint, we’ve got one final step. 

STEP 16 

Paint the firewood rack. But first, wipe it down with some degreaser, then you can grab your spray paint (we used flat black with primer). 

And done! Now all you’ve got left to do is chop up some firewood to fill it. Don’t forget to grab some kindling to fill the bottom part as well. 

Keep in mind that you don’t have to strictly follow the dimensions we’ve used. Just make sure that if you go for a rectangle or 500mm long cross-section bars, you’ll need to adjust all of your dimensions to fit the frame.

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Like most things to do with welding, it’s another feature that’s for your safety. If you’re working on a building site or in a mine, you’ll be required to have a machine with VRD. So, what exactly does it do?

What does a VRD do?

A VRD reduces the open-circuit voltage of a welding machine.

When the welding machine is on, but not being used (like when you’ve just finished an electrode and need to grab a new one), the VRD kicks in and lowers the voltage to a safer level (usually around 13V).

When you’re welding, a complete (or closed) electrical circuit is formed. The power source (in this case, the welder) has electricity flowing through it into the metal, which creates the arc, which creates the weld.

The metal you’re welding is connected back to the welder by the earth clamp, producing a complete electric circuit.

When you stop welding, the circuit stops being closed and instead becomes open. The electricity isn’t going anywhere. It’s just idling inside the power source, like a car idling at a red light. This is called the open-circuit voltage (OCV).

By reducing the OCV when the welder isn’t being used, the risk of being electrocuted is dramatically reduced.

Why is a VRD used?

Your open-circuit voltage will depend on how powerful your machine is. Typically speaking, a stick welder will have an OCV of about 85V, but that can get as high as 110V for really demanding work. On the other hand, your small home DIY stick welder will have an OCV of 50V.

An OCV of about 75V will be able to start an arc on the first strike without the rod sticking, even on stubborn electrodes, like low-hydrogen 7018s.

In normal conditions, open and dry spaces, those voltage levels are relatively safe. The natural resistance in your skin can withstand the zap, and you wouldn’t even feel it with gloves or other PPE on.

However, if it’s damp or humid, that’s where you need a VRD. When your skin becomes wet from washing your hands or sweating in your gloves, the resistance in your skin drops considerably.

If you’re working in confined spaces or off ground level, a VRD is also needed. Accidentally touching the electrode with your bare skin while being in contact with the earth can result in an electric shock, which can be deadly if you can’t get away from the source of it or it disrupts your balance.

Having a VRD kick in and reduce the open-circuit voltage level keeps you safe, which is why you won’t be allowed to work on-site if you don’t have it. They can be internally or externally installed.

How does a VRD work?

The VRD is automatic. It detects the level of resistance against the welding terminal and turns on (reducing the OCV) as necessary.

When the resistance level is high, for example, if the air, your gloves or even your skin is against the machine’s output (the electrode holder for stick welding), the VRD will activate.

When the electrode touches the workpiece, the resistance level drops, which the VRD will recognise and turn off, allowing the open-circuit voltage to increase back to normal levels to start the arc.

When you finish welding and the VRD once again detects a high resistance, it will switch back on after a short delay.

Though the VRD automatically switches off when you begin a new weld, it may react slowly. A delay in reaching a higher open-circuit voltage means it can be difficult to start an arc, as there’s not as much power running through the machine.

Some electrodes, like low-hydrogen or cellulose ones, can often already be difficult to start, so trying to strike them with the VRD active on your welder can be a real struggle.

Note: DO NOT turn your VRD off when you are on-site. Not only is it for your own safety, but it could also be illegal.

A VRD only comes into play if you’re welding without a trigger. When you’re stick welding or lift arc/scratch start TIG welding, the machine is live as soon as it is turned on.

In comparison, MIG welding and high-frequency TIG requires a trigger press to ignite the arc. There is no voltage flowing through the machine otherwise, so there is no need to protect the operator from excess voltage.

Almost every UNIMIG welder has a VRD installed, but it’s not always on. For example, if you purchased a VIPER 185, the VRD would only kick in when the machine was switched to ‘MMA’ and wouldn’t affect your MIG welding at all.

Some people might not love that their stick welds are hard to start, but VRDs are an essential part of keeping welders safe while they work.

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But, if you do have a machine with adjustable inductance, how does it work? 

What is Inductance?

Inductance controls how fast the current rises to reach the amps that have been selected when short circuit welding. Short circuit welding is a type of metal transfer in which the wire connects with the puddle and literally shorts the circuit.

If the welding current could go from almost 0 (when the wire touches) straight to the set max amperage, the wire would feed into the weld rather violently. So, instead of instantaneously reaching the max amperage, there is a short time delay between the start point and reaching the max amps.

That time delay is the inductance, which can be changed to be shorter or longer. The delay is what affects the metal transfer of your weld.

It’s most commonly used with short circuit welding; however, changing the inductance on a spray transfer weld will also have some effect.

Note: For more on what short circuit welding is and the different modes of metal transfer, check out our post on it here.

What does Inductance do?

The inductance changes the characteristics of a short circuit arc because it alters the ‘arc time’. The arc time is how long the arc is touching and providing heat to the weld pool during the short circuit cycle.

Inductance is what allows you to change the frequency of your short circuit – how often the wire touches the joint in the circuit’s cycle. A high inductance means a lower frequency short circuit. A low-frequency short circuit means a longer arc time as it takes longer for the weld current to build back up to the set amps.

The lower your inductance setting, the more frequently your weld will short circuit. A faster short circuit can help to pinpoint a weld in a joint. Less metal is being added, so the bead is narrower and freezes faster. That’s why a low inductance is generally used on thinner metals when you want to avoid burning through.

If you had no inductance set on the machine, you would get a hard and sharp weld pool. However, the lower your inductance, the more explosive the current, and so you get more spatter.

The higher your inductance setting, the less frequently your weld will short circuit. If you set the machine to 100% inductance, you would get a soft, fluid weld pool that wets into the toes well.

That’s why a high inductance is used on thicker metals or on applications like an open root, where full penetration and tying in the toes is a must. The higher the inductance, the less spatter that’s produced.

It might not be the easiest thing to judge while actually welding, but you can hear the difference between a low and high inductance. A low inductance sounds sharper and harsher than the standard bacon crackle that’s associated with a MIG weld. On the other hand, a high inductance sounds much smoother.

For the most part, general fabrication and most standard welding will perform well on whatever the machine comes set at (usually 30%-50% inductance). If your machine doesn’t have an inductance setting, it’s most likely programmed to have between 30%-50% inductance as well.

The actual setting on machines can vary, with some dials labelled with a 1-10 range and others labelled ‘soft’ to ‘hard’. At UNIMIG, our inductance setting reads ‘soft’ to ‘hard’. Setting your machine to soft will give you a high (100%) inductance. Setting your machine too hard will give you a low (0%) inductance.

Keep in mind that while it changes the arc and the weld pool, your inductance has minimal effect on the depth of fusion and penetration of the weld. 

The inductance on a welding machine is one of the many settings that can be fine-tuned to adjust the characteristics of your arc. It only has a minor effect on the overall weld, so the preset setting in most machines will work great on most of your welds.

But, if you have a machine with adjustable inductance, play around with it and see what kind of differences it makes to your weld.

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The problem is that you need enough heat to melt into the thicker piece, but not so much heat that you burn straight through the thin piece.

Thankfully, welding different sized metals to each other isn’t as difficult as it seems, so long as you use the right technique.

Setting Up the Machine

Getting your settings right is the first step to welding different sized metals together. To start, you’ll want to set your machine to the recommended settings for the thicker piece.

For example, if you were stick welding a 3mm plate to an 8mm plate, you’d set your machine to 110A. 110 amps is the lower end of the range that we recommend for a stick fillet weld on an 8mm plate.

You can also choose a thinner filler metal than you would normally use. Sticking with our stick welding example, you’d want a 2.6mm rod rather than the normal 3.2mm that’s used on 8mm. That way, you’ve got less metal to melt, and it’ll melt faster on the lower amp range.

So, if everything is set up for the thicker metal piece, how do you avoid burning through the thinner part? That’s where your technique comes in.

Welding the Metal

Whether you’re tacking your joint or putting down the full weld, you would normally focus your arc on the root of the joint. That way, both sides get equal heat and melt evenly.

However, when you’re working with metal that’s different sizes, you want to adjust your arc so that it’s focused on the thicker piece of metal.

Keeping the Weld Cool

If you find that the weld is starting to get too hot, and you’re worried about the thin piece, move faster. The further into the weld you get, the more heat your base metals will have absorbed, so if you’re MIG or stick welding, speed up your torch movement.

If you’re TIG welding, you can speed your weld up, or you can add more filler. The cooler filler rod will help bring the heat levels down in the joint. You can add more metal with each dab or dab more frequently to achieve this.

The length of your arc will affect how much heat is being transferred as well. The longer the arc, the more volts, and therefore the hotter it is. That’s why maintaining a tight arc (3mm is ideal) is the best way to keep the heat down. This doesn’t apply to MIG welding, as the voltage is fixed to whatever settings you choose.

Heatsinks

If you’re worried about burning through the thinner metal, the other thing you can do is add a heatsink. Aluminium and copper are the most common metals used for heatsinks because they have great thermal conductivity. They help suck the heat out of the weld, keeping the actual join cooler.

Plus, because they’re a dissimilar metal to the one you’re welding, they don’t stick and can be removed easily. (Don’t use an aluminium backing plate on an aluminium weld. You’ll need copper.)

Accidentally Burning Through

If you’ve accidentally burnt a hole in the metal, don’t worry. There are a couple of ways you can fill it in, depending on the type of welding.

MIG

If you’re MIG welding, you’ll need to pause the weld, and readjust your settings. Changing them to be running slightly cooler will allow you to fill the hole in with a series of quick spot welds. Zap, zap, zap until there’s no more hole, and then you can continue the weld. It would be a good idea to leave your settings cooler, to avoid blowing any more holes in your thinner metal.

Stick

When stick welding, you’ll also need to pause your weld. Before you plug the hole, make sure to remove any slag around it. You don’t want to trap any of the flux coating while filling the gap. Like with MIG, it’s a good idea to slightly lower your settings before restarting so you don’t have the same problem.

TIG

Filling burn through holes while TIG welding is a bit easier. If you can see a hole opening up in the weld, you don’t necessarily have to stop. Instead, you can quickly add extra filler metal into the weld pool to close it, then continue as normal.

Quick tip: ‘adding extra filler’ means rather than a small dab, you want to shove a decent amount of the rod into the puddle. There needs to be enough metal deposited to actually fill the hole that’s forming.

Otherwise, you can also pause a TIG weld and readjust the settings.

For more on how to fix holes in your weld, check out our post on it here.

That’s all there is to welding thick and thin metal together. Just keep the focus of your arc on the thicker piece, and you can weld your thin and thick pieces together the same way you’d weld metal of the same size. It’s that simple.

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How and why are some welds colourful?

There’s a decent amount of science behind the how’s and why’s of metal colouring, but we won’t bore you with that. The short of it is that heating steel changes its molecular composition, which reacts with elements in the atmosphere as it cools. This is called oxidisation. Depending on what’s in the air and what temperature the metal is will dictate the colour.

Because the colouring comes from the metal being exposed to the atmosphere and oxidising, it should be avoided on critical welds. Oxidisation can lead to problems with corrosion (it minimises the corrosion resistance), and while you can make a colourful weld that’s strong, it takes a lot of skill.

A coloured weld is not necessarily a ‘bad’ weld, as most colour is the result of surface-level oxidisation. However, anything deeper than surface level is a bad weld and would need to be redone.

That’s why, for anything structural, or really anything integral to what you’re making, avoid colour. It could rust later on, and if you’ve put a nice looking purple weld on your car exhaust, there’s a chance it’s going to rattle itself off.

There are applications where you can get away with some colour. For example, sanitary fields, like dairy and foodservice, will allow for some colour (usually up to light blue). Still, this equipment is also always passivated afterwards to restore the corrosion resistance. Passivation is kind of like an acid bath, and any colours are removed during this process, which is why there is some leeway.

What affects the colours?

Essentially all of the basics of TIG play a role in your colouration.

• Torch angle
• Gas coverage
• Heat input
• Travel speed
• Amperage

Adjusting one of these can impact the others. If you make your torch angle too extreme, you could lose the required gas coverage, or if you turn your amps down, then you have to slow your travel speed to create the proper pool, but this can increase your heat input. They’re all intertwined, so getting good colour on the weld can take a lot of practice and mucking around.

Colour scale

Chrome / No Colour

No colour means no oxidisation, even at the surface level, which makes it the most structurally sound, and you’re not going to have any corrosion issues.

This is usually the colour that the very end of any stainless weld turns because it receives the full post flow duration (as it should to prevent cracking!).

If you’re making art, keep in mind that your last dot at least is going to be lighter than the middle or even beginning.

Straw / Yellow / Gold

These are perfectly acceptable colours. There’s barely any oxidisation, so they look nice while still retaining all the necessary strength needed for a good weld.

Red

Red is the middle ground. If it’s a critical weld, you’re starting to get too warm, but it does look really good.

Blue / Purple

Colours this dark mean your metal was hot when it was exposed to the air, so they’ll have plenty of oxidisation on the surface, even though it looks good. You’ll find that some of your welds that turn out blue or purple (particularly the darker shades) also start to develop the ‘skin’ look (imagine very wrinkled skin) because of this extra oxidisation.

Dull Grey / Black

If you’re getting these colours, the weld has just been absolutely cooked. It was way too hot, and it’s now completely oxidised, not only on the surface but all the way through. All of the corrosion resistance that makes stainless steel ‘stainless’ has been totally burnt out.

To top it all off, it just looks really bad, so even when you’re making art, you want to avoid these colours.

Making Coloured Welds

When it comes to making coloured stainless welds, there’s no ‘one size fits all’. The way you set your machine will vary, and everyone has their own unique way that works for them.

A lot of it is mucking around and tweaking as you go until you find a way that consistently produces colour. There are, however, a few things that you can try if you aren’t getting as much colour (or too much) as you were hoping for.

1. Adjust your angle and heat input

Before changing anything else, play around with your heat input and angle. Of course, this also means increasing or decreasing your travel speed to determine your heat, and changing your angle will also affect your gas coverage. But changing these two things first will generally have the most impact.

More heat means more colour, and a steeper torch angle (like 45°) will severely decrease trailing gas, which means more colour again as the weld will be hotter when exposed to the atmosphere.

2. Gas, gas, gas

There are two things to consider when you’re talking gas. Gas flow and gas coverage.

The gas flow is how much gas is being pumped out of the cylinder. The gas coverage is how much of your weld is being covered by the gas being pumped out. You can have a high gas flow and still have poor coverage, and vice versa.

Because the colours are determined by heat, how much gas hits your weld has a pretty significant impact, as the gas cools things down. However, you still need proper coverage so that it doesn’t become fully contaminated and cause weld defects. You definitely can’t just take it away to get a hotter (see: coloured) weld.

Here’s where gas lenses and gas shrouds come in. Gas lenses can give a more stable gas flow, therefore covering the weld pool with no air pockets or turbulence, as the screen in them spreads the gas more evenly.

More gas equals less colour because the metal will have cooled more before it’s fully exposed to the air. Therefore, a good way to get colour is to put a small gas shroud (ceramic cup) on your gas lens.

You can keep all the benefits of a more stable gas flow while exposing your metal to the atmosphere faster because there’s less trailing gas with a smaller nozzle.

Having a range of different sized gas shrouds will give you the opportunity to play around with gas coverage and see what works best for giving you colour and a protected weld. UNIMIG’s ARC TORCHOLOGY TIG torches come with cups in sizes 4 to 10, so you can get narrow nozzles to wide ones.

3. Try this technique

If you’re not getting the colour you’re looking for, try this to increase your heat input. Lower your amps (not crazy low, say 100A on a 2.4mm tungsten) with a slower travel speed and a gas lens with a #7 (or mid-ranged but on the narrow side) cup.

Then, use a thinner filler rod and add only a small amount in each dab. All of these things keep your piece hot so that you can gain more colours. However, if you can see that your metal is getting too hot, you can add more filler and move faster to slightly cool it.

Otherwise, you can also change your gas shroud to a slightly larger one or turn your gas flow up a little bit if it’s still getting too hot. Running it hot and moving faster is definitely the preferred method, though.

4. Overheating?

If your piece gets too hot, you can end up with a very large heat affected area (this is called the heat affected zone or HAZ). The HAZ is the coloured halo that surrounds a weld. Even if your workpiece is hot, you might not get much colouring, or it might look really faded.

This could be because you’re toeing the line between colour and that dull grey you get from overheating, which you want to avoid.

Pausing to let your piece cool in between passes will help maintain bright colours, keep your heat zone halo thin and lessen distortion if you’re welding thinner metal.

5. Foot pumping

The foot pedal is essential if you’re trying to make a coloured weld. They’re great because you can increase or decrease the amperage at will and add or remove heat as needed.

A foot pedal also means you can do manual pulse welding, which you can play around with for the perfect on the fly settings. If you have a machine that doesn’t have pulse options, then a foot pedal is perfect. If you do have pulse options though, you don’t necessarily need one.

Pulse welding means you have more control over the heat and can, in general, keep the piece cooler because the arc is fluctuating between a high and low point. While this is good if you have a uniform, straight line, all the same size weld, it’s not so simple if you’re doing artwork.

If you’re trying to make a creative piece, and a line starts thick and ends thin, you’d need to go back and change the frequency that your arc pulses at every time there’s a change in line weight. That’s why, when you’re making coloured welds, manual pulsing is great; you can adjust how it pulses as you go without stopping and starting your weld.

The best way to use your manual pulse, or foot pumping, is by backing off when not adding filler and then pumping it (putting your foot all the way down) as you add filler. The burst of heat helps to melt the metal and make the actual weld hot while keeping the workpiece cooler.

Note: If you’re using a TIG machine that lets you input settings like start amp, up-slope, down-slope and finish amps, you don’t need to program these in when using a foot pedal, as that’s all dictated by the pedal and any machine settings will generally be overridden.

6. Post flow

Post flow is needed for all TIG welding, as it helps cool the weld (as well as the tungsten) and protects it from contamination.

Unlike MIG welding, though, you can adjust the amount of post flow at the end of the weld. Even if you’re making a colourful stainless steel weld, you need post flow.

It sounds counterproductive. Why do I want to cool my weld when it’s all about heat? There’s a good reason for it, though.

Your stainless is not immune to weld defects. Yes, your post flow will probably make the end of your weld lighter than the rest, maybe even colourless. But, without it, you’re compromising the metal entirely and likely to get a dull grey colour or cracks at the end instead because the metal was contaminated (while in its liquid form) by not letting it cool.

How much post flow you give to a weld is personal preference, but when you’re trying to leave it coloured, a good starting point is around 4 to 6 seconds.

7. Metal thickness

Your metal thicknesses impact how the colours will turn out. Thicker base pieces will take longer to heat and form puddles, and thicker filler rods will need more amps to melt them. The filler rod also cools the weld pool (cool metal in hot pool = cooled pool), so how much filler you add will affect the colour.

When you’re practising making colours, it’s a good idea to start with a thicker base metal as it’ll be able to absorb more heat without your weld going black or blasting through it entirely.

8. Outside influences

Your environment is going to have an influence on your weld. What that means is if you’re in your garage and you’ve got the door closed, your colours could turn out perfect, and you’ve finally found the right settings.

Open the garage door, or change the room temperature drastically, and those settings are straight out the window.

Things like a breeze, even if it’s a light one, can make a real difference to the gas coverage (by blowing it away), and a freezing room can change how cold your base metal starts, which affects how fast it absorbs the heat.

Trying to keep your workspace as controlled as possible while you’re still learning will definitely help with mastering the settings.

9. Etching

If you’re making a proper art piece (as opposed to practice beads or otherwise), drawing an outline as a guide means you can perfect distances and shapes and check symmetry.

Once your drawing is spot on, running over it with an engraving pen will give you sharp, easy to see lines that you can follow as you weld.

Make sure you re-clean your workpiece super well (with acetone or equivalent) afterwards though, permanent marker residue in your weld is probably going to cause contamination.

10. Colour control

You can’t control the colours you get.

Yes, there is a colour order based on the heat input. Yes, more heat means more colour. Regardless of both those facts, it’s really hard to consistently predict or even achieve the same colour all the way across a weld.

If you’re doing a continuous weld, there’s a good chance it alternates between gold, red, blue and purple in a random order. Maybe it starts purple and then fades red before going blue and then turns gold.

No, this doesn’t really make sense, considering the material heats up as you go. You’d assume the start would be gold and the end purple, but in reality, it’s hard to control, and there’s no guarantee that it’ll come out the exact colour or order that you were hoping for.

You can even get more than one colour on the same dab. Sometimes your bead is half gold and half purple. Even though heat dictates the colour, and a weld gets hotter as you go, there are other variables.

You still have control over the amps (especially seeing as you should be using a foot pedal), your filler metal dabs might not be even, and are you keeping your travel speed consistent? These things have to be factored in, which makes it really hard to try and weld an exact colour, especially given you can’t actually measure the metal’s temperature.

If you’re making art, don’t set your heart on a design that HAS to be red, blue, or otherwise. If you get good colour, it’s a win. Don’t forget that if your weld is too hot, you’ll burn out all the properties in the metal, which will leave it that dull grey you’re trying to avoid.

11. What if I want no colour?

If you want to get a chrome-coloured weld in your artwork, keeping the weld cool is key. A good way to do this is to pick up your travel speed, increase your gas flow (not too much that you get turbulence, though), make sure you’re using a gas lens, chuck on a bigger gas shroud and add more filler if possible.

Maybe you won’t need all of these, but they each help to keep the weld puddle cooler and less coloured. A non-coloured weld on the artwork can work for borderlines or make details pop because they’ll stand out against the colours. 

12. Finishing touches

You can’t clean your art piece once it’s done, not properly anyway. On a typical weld, you would go over the final result with a wire brush just to make sure it’s clean.

However, because the colours can come off, as they’re only surface level, you aren’t going to be able to clean the final product. Any heat affected zone (HAZ) halos will remain on the piece.

You can, if you have open spaces and the patience, sticky tape over the welded sections and run a wire brush or scuff pad over those spaces to remove any of the discolourations there. Having shiny clean spots will make your colours pop, but sometimes it’s just not possible.

Having these halos is not always a problem. They can create their own rainbow colouring as well, which gives its own effect to a piece.

Producing a colourful weld definitely takes a bit of trial and error, but hopefully, these tips help to get you started, and if they have, you should shoot through some photos of what you’ve created!

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A few applications that’ll require a vertical up weld include structural welds on buildings and pipe welding. A lot of those welds will be done on thick, heavy metal, which you can’t just lay down and move later.

Thanks to gravity, it’s one of the harder positions you can weld in, but it’s a great skill to have. Though it can be challenging to learn, there’s a trick to perfecting your vertical up weld every time, whether it’s MIG, TIG or stick.

Welding Up With MIG

In general, vertical up MIG welding is done much the same way as standard MIG welding, with just some minor changes. To get a good, penetrative vertical up weld, all you need to do is turn your settings down and make triangles. Not sure what that means? Let’s explain.

Get the Settings Right

When you’re welding upwards, you’re fighting against gravity. That means if your weld pool is too fluid, you’re not going to be able to control it properly. You’ll find most of it ends up dripping down or falling out of the joint.

That’s why turning your settings down is the first step to getting a good vertical weld. They don’t have to be super low; you still want to get enough heat in the metal to penetrate it. Whatever settings you would typically use for a down hand weld, we recommend decreasing your volts by about 3 or 4 and your wire speed by about 5 or 6.

Here’s an example: say you’re welding 6mm steel with 0.8mm wire. For a standard weld sitting flat on the bench, your settings should be around 23V (volts) and 12m/min (wire speed). If you wanted to weld vertical up on that same metal, you’d drop your settings to look more like 19-20V and 6-7m/min.

Once you’ve adjusted your settings so that your weld isn’t falling out, the second step is your technique. That’s where the triangles come in.

Making Triangles

The triangle technique is exactly what it sounds like. You want to move your torch in such a way that it looks like you’re drawing triangles. Using the triangle technique, you can maintain control over your weld pool and get proper penetration into the joint.

Moving your torch around in a triangle shape will also help spread the heat out. Rather than being focused in one spot, the heat is constantly moved around the joint, keeping the overall temperature down.

So, how exactly do you do that? When it comes to vertical up, you don’t want to start in the middle of the joint. You want to start your arc angled to one side. Whether you’re doing a butt weld or a fillet weld, you’re going to have a left side piece and a right side piece of metal.

It doesn’t matter which one you start on. Let’s say you start your weld on the left. The first step is to move your torch from left to right, going straight over the joint. You want to build a base to start with before moving into the rest of the triangle motion.

Once you have a base, the next step is to weld diagonally up into the joint. Your torch should move from the right-hand side up into the centre of the joint. Next, weld diagonally down to just above where the weld started. The entire motion looks like a triangle. That’s the first triangle done. Now you can just repeat the steps: straight, diagonal up, diagonal down.

Keep the torch as tight in the joint as you can, and you’ll be able to maintain control over the weld pool, leading it where it needs to be.

To get the best result, pausing momentarily on the sides and punching into the middle will help with penetration and get the weld to sit in the joint flatter.

Upside Down V Technique

The triangle technique is not the only one that can be used to weld vertical up. There’s also the upside-down V. It looks and works exactly the way the name suggests, and the principle is the same as the triangles.

The three points of the V will have you wetting into both sides and punching into the middle.

For the most part, vertical techniques all aim to do the same thing: keep the weld pool in the joint and punch into the corners and the root.

Once your root run is done, you won’t need to use the triangle (or any other) technique on second or third (or more) runs. Your second and third runs should be made to strengthen or cap your weld, so all that torch manipulation isn’t necessary.

A small weave will suffice, pausing on the edges to ensure everything is blending in together. If you’re not pausing on the edges, you risk getting undercut in the weld. Undercut is a weld defect that will need to be fixed. Keep your edges tied in, and you’ll finish with a professional-looking vertical weld. 

Welding Up With STICK

Just like with MIG, when it comes to vertical stick welding, gravity is the biggest challenge. Besides adjusting your settings, however, it’s also about picking the right electrode for the job. There are a range of electrode types, each with its own properties, that can impact how well it will work in the vertical position.

Picking a Stick Electrode

Every electrode has a classification stamp on its end. Steel electrodes come with an ‘E’ followed by a 4-digit code (e.g. E6013) stamped on their end. The E simply stands for electrode. The first two numbers (60) represent the tensile strength, the third (1) indicates the positions it can be used in, and the fourth (3) refers to the type of coating on it.

When you pick your electrode, you’ll want one with a tensile strength the same or more than your base metal. Its third digit should read 1, which indicates that it can be used in all positions, including vertical up. You’ll also want a coating that isn’t too aggressive or digging, as it’ll be much harder to control while going uphill.

For more on electrodes and which one you should use, check out our Ultimate Stick Welding Guide.

Push or Pull?

Once you’ve got the right electrode, the next thing to consider is the technique. Unlike any other kind of stick welding, vertical up is the only time you’ll want to push the weld. It shouldn’t be a steep pushing angle, but if you tried to pull the weld up, it would just fall out.

The reason you want to push rather than pull is because it provides the penetration. Pulling molten metal uphill isn’t going to sit in the joint, let alone penetrate. By pushing, you can be sure that you’re getting adequate penetration on the weld.

When pushing a weld, you’ll want to have a travel angle of 10°-15°. That’s also true of vertical up stick welding. Your electrode should be pointed at the centre of the joint (e.g., perpendicular/90° on a butt weld) and then lowered slightly.

Lastly, make sure to keep your arc as tight as you can without sticking the electrode. Keeping a tight arc will help you control the puddle, and it’ll keep the voltage lower. The longer the arc, the higher the volts and the hotter the weld.  

Vertical Up Stick Welding Technique

As well as being the only time a stick weld is pushed, you’ll also need to manipulate the weld as you go vertical up a joint. Generally speaking, stick welding is used on thicker materials. You’re not going to be welding car panels with it. With that in mind, most welds that have to be done vertical up will be relatively thick (around 6mm+).

When welding thicker metal, you’ll almost always be welding into a corner of some sort. Even if you’re doing a butt weld, if you’re working with metal that thick, it’ll be bevelled. If it wasn’t, you’d never penetrate all the way through. So, you’ll probably need several passes on 6mm or thicker plates. That’s where vertical up stick differs from standard stick welding.

Like with MIG, your first run should be done with the triangle technique. Pausing on both sides of the weld and punching into the centre will help bridge the gap and provide penetration.

Once your root run is done, if you need a second run, you can just weave. When it comes to the weaving, you want to make sure that you’re zigzagging from side to side, spending more time on the sides than the middle; the middle will take care of itself.

There’s no need for as much manipulation, but you do want the weld to fill the gap and wet into the sides. When done well, the ripples in your weld should be close together, which is sometimes referred to as the rope effect.

Take Your Time

Stick welding vertical up is a slower process than usual. If you try and rush through it, you’re more likely to lose the entire weld. It’ll fall out and drip down, and you’ll need to start again.

Then there’s the fact that it’s stick welding. You’ll need to chip off the slag after every pass, especially if you need to do several. If you don’t, you’ll get slag inclusions, which are a weld defect.  

Make sure you spend some time getting the settings right. If you have a tight arc and are moving slowly, but your puddle is still too fluid, lower your settings. There’s a good chance your amperage is too high, and turning it down will make your weld much easier to control.

In general, stick electrodes come with a recommended amperage range. For the most part, using the lower end of that range will provide enough heat to penetrate without sending your weld pool crazy.

However, it might not always work that way. If you’re welding metal that’s on the thicker side, you might not be able to stay in the lower range. For example, welding 8mm mild steel with a 2.6mm electrode. 8mm is about as thick as that electrode will weld, so turning the amps down might mean it doesn’t even melt.

Note: If you’re welding on anything structural, use the recommended electrode size. In the case of 8mm steel, that would mean using a 3.2mm diameter electrode.

If you’re not sure what the best settings would be, we recommend starting with your amps lowered by about 10. Grab some spare metal that’s the same thickness and practice on that. If you find the weld is too fluid or it’s barely melting, adjust your amps by 5 until you find the sweet spot.

Welding Up With TIG

TIG welding vertical up is actually done the same way that all TIG welding is done. So, there are no extra techniques or anything special that needs to be done.

Most TIG is done on thin metal; it’s designed for lower amperage welding. If the amps are already relatively low on thinner metal, there’s no need for extra manipulation to aid penetration. Instead, you can just dab in your filler metal the way you always do.

There are only two things you need to do. The first thing: make sure you can see your arc. If you can’t see what you’re doing, it’s not going to go well. The second thing: make sure you can feed your filler rod in.

Welding vertical up might not be the most common kind of welding there is, and it’s definitely the hardest, but that doesn’t mean you shouldn’t give it a go. It’s still a valuable skill to possess, it’s perfect if you’re looking to take your welding career to the next level, and just like everything, all it takes is practice.

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TIG gases

TIG welding will only work with inert (noble) gases. There are six inert gases, but only two of them are cheap enough to be used: argon and helium. That means picking a shielding gas is relatively simple. Pure argon is used for every application: mild steel, stainless steel and aluminium.

Helium can also be used, but it’s more expensive, so it is usually only added to argon as an extra to give more penetration. For example, if you were welding on really thick metal and you were reaching the limits of your welder’s amperage range, you could swap to an Ar/He mix. Helium is common in colder climates as well, as it burns hotter, so it provides more heat and penetration for the weld.

Why can’t semi-inert (active) gases be used?

Inert gases have only one function when being used to shield a weld: shielding the weld. They’re denser than the surrounding air, so they can completely block out any oxygen or otherwise, that would contaminate the weld. They have no effect on the welding process, and there are no changes to the arc.

On the other hand, active gases like CO2 and oxygen do have an effect on the weld. They can alter the characteristics of the arc, as well as aid with penetration, so they do more than just shield the weld.

Unlike MIG welding, which benefits from having active gases mixed in, TIG is not so forgiving. Because CO2 and oxygen affect the weld directly, it reacts badly, and the added heat can blow holes through the workpiece, plus it burns up the tungsten. By only using an inert gas like argon, the weld and your tungsten will both be properly protected.

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Each consumable can be changed: the back cap comes in different lengths, you can get clear cups to see the weld better, and you can swap your collet body out for a gas lens. But, what’s the difference between a collet body and a gas lens, and why would you swap?

Collet Body

A collet body is one of the standard consumables that make up the assembly of a TIG torch. They do two things at once: hold the electrode in place and allow the shielding gas to blow over the weld.

But just because they’re what comes standard in a TIG torch, does that mean they’re the best?

A collet body releases a broad plume of gas over the weld pool to keep it shielded. The gas being pushed out of the torch is filtered through several small, specially designed holes at the end of the collet body.

The force of the flow is what pushes the gas out, so there’s no real direction except out, which can lead to turbulence.

Turbulence in the shielding gas can lead to spotty cover, so even with the perfect torch and work angle, you might find defects – like porosity – in your finished weld.  Despite everything being right, it can still happen because pockets of air get trapped in the gas as it is expelled from the torch.

Gas Lens

A gas lens replaces the collet body in the assembly of a TIG torch (but not the collet itself!), so it does the same things for the most part. It holds the collet in place and distributes shielding gas over the weld.

However, unlike a collet body, rather than a few holes, a gas lens comes with a diffuser and a mesh screen (it looks like a mesh doughnut around the centre, where the electrode sits). The diffuser and mesh screen means that the gas is dispersed evenly across the weld pool in a laminar pattern, with way less turbulence.

Advantages of a Gas Lens

• More gas coverage
• Less turbulence in the gas
• Allows the tungsten to stick out further for better visibility and getting into tight spaces
• A cleaner gas and a cleaner weld

Although the collet body is the consumable that comes with the torch, it’s not the best option, though it’s still not a bad one.

As with all welding consumables, collets and gas lenses come in multiple sizes to match the size of the electrode you’ll be using. So make sure, regardless of which you choose, that it fits the size of your tungsten electrode. For example, a 2.4mm electrode will need corresponding 2.4mm consumables, including the collet body or gas lens.

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There are a few different gas mixes that you can get, and they all do slightly different things. Unfortunately, there’s not a one size fits all when it comes to getting gas for a weld, so which one is going to work best will depend. The type of metal you use, the metal transfer method, how thick your workpiece is – it all makes a difference.

Gas Types

Inert Gas

Inert gases don’t react with external elements (like oxygen and nitrogen), which makes them great shielding gases. Only argon and helium are cost-efficient enough to be used for welding.

Active Gas

Active gases react with external elements, which can affect the arc’s stability, weld penetration, and spatter amount. Active gases are only used on ferrous metals and only in small quantities (as large ones would be damaging).

Semi-inert gases, like carbon dioxide, are a combination of inert and active gases. Because they react with the weld pool, they’re classified as active gases.

MIG Gases

If you’re going to be MIG welding, there are two main gases that are used: pure argon and an argon/carbon dioxide mix. The most common (and recommended) Ar/CO2 mix is a 75/25 ratio, with 75% of it being argon and 25% of it being CO2.

Which one is used for what?

When you’re working with mild steel or stainless steel, you’ll want to use an Ar/CO2 mix.

If you’re working with aluminium, then you’ll want to use pure argon.

Pure argon (an inert gas) gives shallow penetration but a wider bead profile in a weld. It also results in less spatter.

CO2 (a semi-inert gas) can be used on its own, as it gives deeper penetration than argon (plus it’s cheaper). However, it produces a harsher, less stable arc, which results in a lot of spatter.

Combining the two gives you a fully penetrative weld and good arc characteristics without a crazy amount of spatter. That’s why a 75/25 Ar/CO2 gas mix is the best for mild and stainless steel. These days it is often advertised as ‘MIG gas’ as well.

Other gases and their mixes

Argon/CO2 mixes:

While argon and CO2 can both be used on their own depending on the application, and a 75/25 mix produces great results on most things, there are a few other combinations that work.

98% Ar/2% CO2

This mix is called C2 and is generally used on stainless steel. It’s a cheaper option than a tri-mix (see below) but works in the same way.

82%-92% Ar/18%-8% CO2

This mix (anywhere in the range works) is used when using the spray transfer method. Straight CO2 or the standard Ar/CO2 mix is limited to short-circuit MIG, so the gas needs to be adjusted in order to spray transfer.

Helium

Like argon, helium is an inert gas and is most commonly used in colder climates. It burns hotter than other gases, so it gives deep penetration to the weld. That’s why it is often added in small dosages to argon, which allows you to work on thicker materials with ease.

However, helium can be quite expensive, so even though it can be used on its own, it’s more often only used as a mix. The only exception to this is when it is used in tri-mixes for stainless steel.

Helium mixes:

• Ar/He
• He/Ar/CO2
• He/Ar/O

A tri-mix can be used with stainless steel for extra penetration, with 90% helium, 7.5% argon and 2.5% CO2/oxygen. The helium provides the needed heat while the CO2/oxygen helps with penetration and stabilising the arc.

Oxygen (an active gas) can be added in very small amounts (1%-5%) to increase the penetration of a weld and stabilise the arc. It is a cheaper alternative to helium and works better on ferrous metals.

Oxygen mixes:

• Ar/CO2/O
• Ar/O

Oxygen is only added in small amounts, thanks to excess amounts being damaging. Shielding gas is needed to keep oxygen (and the resulting porosity) out of the weld pool. Adding too much to your shielding gas will have the same effect as having no shielding gas.

What happens when you get it wrong?

Choosing the wrong shielding gas isn’t recommended, and it’ll leave you with some unwanted weld defects.

If you were to use pure argon as your shielding gas for a weld on mild steel, more often than not, you’ll be left with an inconsistent bead and lots of spatter.

If you used a highly penetrative mix, like an argon/helium mix, on really thin metal, then you’ll spend more time blowing holes through it than you would actually welding it.

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Short Circuit

Metal is transferred by the short circuit mode when the wire connects with the puddle and literally shorts the circuit. That’s where it gets the name ‘short circuit’. This shorting occurs roughly 20 to 200 times a second and is what creates the ‘crackling bacon’ sound. It’s run on the standard ArCO2 75%/25% gas mix, but it also works with straight CO2.

Short circuit is the most common mode of metal transfer, especially for hobbyists, as it’s done with low volts. It can be used in every position – flat, horizontal, vertical, or overhead – so you’re not restricted like you are with the other modes.

Short circuit works on up to 8mm thick metal. Anything thicker than that, you’ll need to run hotter to get proper penetration (automatically bumping you up into globular transfer anyway).

Globular

Metal is transferred by the globular mode when the wire creates globs of molten metal on the tip that fall into the puddle to make the weld. It looks like a small ball is constantly forming and reforming on the end of your wire (which it is). It can be run on the standard ArCO2 75%/25% gas mix or on straight CO2_.

The bead appearance isn’t as smooth, and the process itself can be pretty messy with excessive spatter, but it has good penetration.

Globular is hotter in value, with more wire feed speed and voltage than short circuit, so the weld pool is more fluid. Because the pool is more fluid, you’re restricted to flat and horizontal positions only.

Spray

Metal is transferred by the spray mode when the amps and voltage are high enough that the wire begins to spray tiny droplets into the pool. It looks like a needle spraying from the wire into the puddle, similar to a pressure washer hose. Unlike short circuit and globular, spray needs to be run on an argon mix of 82% or more.

It has a much smoother sound than short circuit, with little crackling, almost like a low hissing. The spray method is good for heavy fabrication and thick material as it has a deep penetration profile.

However, it’s so hot and fluid that it’s not suitable for vertical up, vertical down, or overhead welding. It’s a much cleaner process, though, with almost no spatter.

Pulse Spray

Pulse spray is similar to the standard spray method, but it ‘pulses’ between the set amps (the peak amps) and a low point. Having a low point means that the weld has a moment to cool each time, making the pulse spray transfer more versatile. Because the weld pool has time to (briefly) cool, it isn’t as fluid, so it can be used in more than just flat positions.  

Pulse spray still needs an ArCO2 gas mix of 82%/18% (a 92%/8% mix is the most commonly used). It also requires a machine with the ability to pulse MIG.

From short circuit to globular to spray, you’re getting consistently hotter, with deeper penetration and less spatter. There are no exact amps/voltage cut-offs that determine when your short circuit becomes globular or spray. You’ll have to tell by sight and sound which type of transfer you’re getting.

In general, though, it will spray if the volts are too high for the wire feed speed. On the other hand, the faster your wire speed, the more wire is introduced to the pool, so you’ll likely be short circuiting.  

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Each site you look at says something a little different, and the colour coding seems to change between brands. We’ve broken it down into a quick and easy guide with the Australian standard colours, so you can find the tungsten you need hassle-free.

What’s in a Tungsten and What Do They Do?

Every tungsten is roughly 95%+ pure tungsten (which used to be the only kind of tungsten you could get) with some additional ingredients mixed in for better results in certain areas.

Thoriated tungstens were the second type of tungsten that became available, so a lot of the time, they’re used as a reference point when comparing how the other (newer) tungstens perform.

2% Thoriated (red)

These tungstens contain a small amount of thorium mixed in with the pure tungsten. Thoriated tungstens were the first to have an oxide mixed with pure tungsten. They can’t be used for AC (the tungsten just burns back into the cup if you try), but they perform well on DC.

In technical terms, the added thorium boosts the electron emission qualities in the tungsten. In simple terms, the added thorium means the tungsten needs a lower amount of heat to start and maintain an arc, which has a bunch of benefits: 

• Good arc starts
• A very stable arc
• A high current carrying capacity
• It operates below its melting point, which improves its lifespan significantly
• It doesn’t spit, so there’s less chance of contamination
• It maintains a sharpened point

They used to be the best for any DC TIG welding, but they’re no longer as popular. The problem? They’re radioactive. The risk is minimal, but the problem occurs when the thorium enters the lungs.

While welding with a Thoriated tungsten isn’t dangerous, prepping them can be. Preparing the tungsten with a grinder means that the previously trapped thorium is now out in the air, where it can be dangerous. Unless your contract requires you to use them, it’s best to find an alternative (like Lanthanated).

1.5% Lanthanated (gold)

These tungstens contain a small amount of lanthanum mixed in with the pure tungsten. The added lanthanum in the tungsten gives it a roughly 50% increase in its current carrying capacity (compared to Thoriated).

Note: The current capacity of a tungsten is how many amps it can be run on before it starts to deteriorate.

Lanthanated tungstens also work well on both AC and DC, plus they have:

• One of the best arc starts (especially on DC)
• A very stable arc
• A low burn-off/erosion rate, so they last a long time
• Excellent re-ignition (no sticking on restarts)
• They don’t spit, which means less weld contamination
• They can strike and maintain an arc at low or high amperages
• They can be sharpened to a point (which keeps its shape well), or they can be balled

Lanthanated tungstens also share the same conductivity characteristics as Thoriated tungstens.

Note: These characteristics mean that electricity passes through them with the same amount of ease, and they conduct heat in the same way.

Unlike Thoriated electrodes, they aren’t radioactive, which is why they’re considered the best general-purpose tungsten and a good replacement for Thoriated.

0.8% Zirconiated ( white )

These tungstens contain a small amount of zirconium mixed in with the pure tungsten. They can’t be used for any DC work, but they’re perfect for AC. Why?

• They ball well and retain the shape
• They have an incredibly stable arc
• Zirconium is a strong metal, so it doesn’t split or spit and contaminate the weld
• It handles high amps well (perfect for aluminium)
• Its current carrying capacity is the same as (and sometimes better then) Thoriated

They’re the go-to tungsten for all of your AC welding because that’s what they’re designed for.

Rare Earth (purple)

Rare Earth tungstens have a mix of different oxides added to them, which can vary depending on which brand/where you get them from. UNIMIG’s Rare Earth tungstens are a combination of lanthanum (1.5%), zirconium (0.08%) and yttrium (0.08%). The combination of several oxides together means it works great on AC and DC, plus:

• Great arc starts
• A very stable arc in AC and DC
• One of the longest electrode lifespans, with less re-grinding needed than usual
• Little spitting
• The ability to use a smaller diameter tungsten on a job
• Can handle high amperages (even with a smaller tungsten)

Rare Earth tungstens also share the same conductivity characteristics as Thoriated tungstens. Some brands refer to Rare Earth tungstens as ‘Chartreuse’, but they’re the same thing.

2% Ceriated (grey)

These tungstens contain a small amount of cerium mixed in with the pure tungsten. Ceriated works best on DC, though it does still run on AC. It’s the most popular tungsten when it comes to welding thin materials, thanks to some of its unique properties:

• Excellent arc starts at low amps
• It runs best on DC with low current settings
• Good re-ignition
• Great arc stability

Because of the way cerium oxides behave when they’re heated to extreme temperatures, it’s not recommended to use them on high amperage applications.

Higher amps cause the cerium to concentrate at the tip of the tungsten electrode (at the hottest point). That means the rest of the tungsten is empty of its added oxide, rendering any benefits null and void.

On the flip side, because cerium works so well on low amperages, Ceriated tungstens are perfect for use on sheet metal and thin piping or tubing.

Which Tungsten Do You Need?

We’ve ranked each type of tungsten based on their performance in certain conditions and material types, but what do all the dots on our chart actually mean?

Arc Ignition

How easily does the arc start? A good arc ignition will look slightly different depending on how you’re creating it (lift arc vs high frequency), but it should generally look like a flare of light with a soft ‘puff’ noise. A good arc will come out in a cone shape.

A few factors can contribute to how your arc starts, but if all your machine’s settings are correct, and your tungsten still starts with little light and remains dull or weak-looking, it doesn’t have a good arc ignition.

Tungsten Life

How long does the tungsten last before it needs grinding, or do you need a new one? Tungsten has the highest melting point of any metal on the periodic table, but that doesn’t mean it will last forever.

Every tungsten handles amp rates differently, and the higher the amps, the faster some tungstens lose their tips. There are a few things that will make your tungsten last longer.

One is proper tip preparation: grinding the end of the tungsten to a point or ball, depending on the application.

Two is being careful not to dip them, which is explained below. Both of these are a great way to make the most out of your tungsten.

Arc Stability

Does the arc flicker or blowout? Is it consistent all the way across the weld? Once the arc has started, it should look like a cone-shaped light that remains totally solid. It shouldn’t flicker, or wander, or blow out if it is stable.

Some things can affect this, like using low amps on thick electrodes, or AC, which is more likely to flicker even when stable, and pulse welding will flick in and out as the arc moves between amp ranges. In general, though, your arc should be steady and maintain that cone appearance for the entire weld.

Resistance to Contamination

How easily does the tungsten become contaminated? One of the main ways that a tungsten becomes contaminated is by dipping it. There are two ways you can dip.

The first way is by touching the tungsten itself into the workpiece. Not a lot will stick to the tungsten generally, and your weld pool should be relatively clean anyway, but if your tip has touched the pool, it will cause a blast of oxide and other contaminations.

When you stub your electrode, you might not always lose the tip’s shape, but the next time you weld with it, it’s going to blow all those contaminants into the start of your weld.

The second way to dip your tungsten is by touching your filler metal rod directly onto it. Instead of the rod melting into your weld pool, it is now coating the outside of your electrode. This causes instant contamination of your tungsten, and a lot of the time it’ll cause the arc to wander.

Long term constant use of the same tungsten will also naturally build up contaminants, like discolouration from the gas and oxidisation, even if you’re cleaning it regularly.

If you’ve dipped your tungsten into the weld pool, don’t worry, you aren’t the first, and even seasoned welders slip up sometimes. It can be a bit of a pain, as you’ll need to re-grind it into shape before you can continue to use it.

If you’ve dipped the filler rod directly onto the tungsten, these can still be salvaged and re-ground; you’ll just need to snap the contaminated end off. This is also true of long-term use contamination and discolouring; you can snap the contaminated part off and grind it into shape until it gets too short to use.

Tungstens that are more resistant to contamination will not suffer as much discolouration or have as many contaminants stick to the tungsten if it is dipped and will take longer to ‘dirty’ from extended use.

AC Performance

How well does the tungsten work when used on an alternating current? AC welding is only used when welding aluminium or magnesium alloys, as you can’t use DC for them.

AC means that the current flows both ways, and a cycle is completed when it has flowed one way and then back the other way. This back and forth of the current has different effects on tungstens than DC (direct current) does, and some tungstens are better suited for AC applications.

‘What happens if I use a Thoriated (or any other DC-specific) electrode on AC?’

We asked ourselves the same thing. The answer: you ruin the tungsten.

When the button is pressed (for high frequency), the tungsten fizzles and burns up back into the cup, and there’s no saving it. We definitely don’t recommend trying it, and if you need to weld aluminium, Zirconiated tungstens are the best.

Find the full range of UNIMIG tungstens here

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Just like with any welding, your metal should be clean. That includes the inside edge of the hole as well. If it’s a really thin piece of metal, it won’t matter so much, but where possible, run a grinder or sander over it so that it catches the inside and gets rid of anything that might contaminate your weld.

TIG Welding Holes

To fill a hole with TIG, you just dab, dab, dab in a circle around the edge of the hole to start building it up, trying to lead it so that it’s filling the inside edge rather than sitting on top.

It’s like welding on a fillet joint (which is exactly what it is if the hole backs onto another piece). You may need to go around a few times, but once it’s a small enough hole, you can hold your filler rod in the middle and fill in the rest.

The reason you want to go around the circle is to make sure you’re melting into all the edges. If you don’t, you could end up with air pockets in the weld.

Blasting it at the end might cause it to cave in, so as you end the weld, add a bit more filler to make it flush. It’ll only cave in if the backside is open, though.

If it does cave in, once you’ve filled the top side, flip your piece over and run the torch over the backside so the metal properly melts into the edges and there’s no undercut. When you end the weld, move your torch away from the centre, towards one side as you finish.

Now that you’ve finished the weld, go ahead and grind off any metal that protrudes to make it flush. If you’ve got any dips or missed spaces or spots that haven’t been filled properly, go ahead and add another layer of weld to fill it up.

If you add extra filler in, you can push it around with the torch while it’s still liquid and spread it around a bit and get it to ‘wash out’. This is extra helpful on thin metal, especially if you’ve already been blowing through it.

When there’s nothing to back the hole, and it’s not perfectly circle, you want to try and start on a solid or thicker part so you can create a pool and build up the edge. That way, you have a base to start on and can work up to bridging both sides.

If you’ve got an open hole, you can use a copper backer to help hold the weld pool in place. When TIG welding, just clamp the backer into place. The copper won’t stick to your weld, and it’ll keep it from caving in. However, depending on accessibility, it might not always be possible to use one.

MIG Welding Holes

To fill a hole with MIG, it’s the same process as it is with TIG. If you can, use a copper backer. For smaller holes, just a spot weld and it’s filled (with a backer). If it’s a larger hole, build up an edge and go around the hole, filling it in.

It’s best if you do the fill as a series of spot welds, just to keep the heat minimal. If you’re filling in a burn through, keeping your heat input down is best because you don’t want to make it wider.

If you’re using a copper backer, aim your weld at it, especially on thin metal. If you aim your weld at the edge of the metal, it could blow away instead because your settings are too hot and you’ll be left with an even bigger hole. Copper backers are great for MIG welding holes – especially burn throughs – because they’re heat sinks, so they’ll absorb excess heat.

When you use a backing plate, watch the weld doesn’t ‘sugar’ on the backside. Sugaring is most common in pipe welding when the back of the weld isn’t being shielded by gas.

Oxygen and other contaminants affect the weld, and it can look like it’s covered by a layer of sugar. If your weld sugars on the backside, you can take a grinder to it, get rid of the crystals, and weld that side so that the hole is fully filled and contaminant-free on both sides.

If you have a big hole, 1cm or more in diameter, and/or you can’t get to both sides of it, it’ll be easier to plug it. To plug a weld, cut out a circle that’ll fit snug, spot weld it in and grind it flush afterwards.

If the hole you’re filling is on a thicker piece of metal, cut your plug from a thinner piece of metal (around 5mm thinner). That way, you can tack in the plug and have room to fill in either side of the plug with weld metal.

If you’ve only got access to one side of the hole, cut your plug from metal that’s only 2mm-3mm thinner. You can grind everything flush once it’s done. Leaving space to fill with weld is just extra security to make sure your hole is properly sealed, and the plug has been fully melted into the outer edges.

You can plug holes of any size with both MIG and TIG, but it might be less time consuming to fill them with a weld if they’re small.

Filling holes in your weld might take a bit of patience, and sometimes it takes a bit of readjusting your settings if you’re burning through. But, once you’re done, most of the time (with a bit of grinding), you won’t be able to tell there was ever a hole in the first place.

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One: the welding problem of burnback on a contact tip. Or, two: the adjustable burnback control available on some MIG machines.

Despite being two different things, burnback controls most likely got their name because they’re used to eliminate the welding issue. So, what are they both, and what do they do?

What is Burnback?

Burnback happens when your wire arcs at the opening of the contact tip and burns back into it, welding itself to or inside the tip. Burnback is specifically a MIG problem, as it only occurs with a continuously fed wire through a small contact tip opening.

Once your wire has burnt back, it’s game over. You’ll have to remove the contact tip and start again. Even if it only welded to the contact tip a little bit and you could file it off, just get rid of it. The leftover residue will make it more likely that the wire burns back again, not to mention the potential weld contamination it could cause.

What Causes Burnback?

Wire feed speed is too slow

A slow wire feed speed means that the arc is melting the wire faster than it’s coming out of the machine. If it’s burning faster, it’s only got one place to go, and that’s back up the wire and into the contact tip. Holding the torch too close to the workpiece

The closer your torch is to the workpiece, the easier it is for your arc to jump up into your nozzle and contact tip.

Erratic wire feeding

Erratic wire feeding usually happens because the filler wire hasn’t been tensioned correctly. If you’ve added too much tension, the wire will struggle to feed, and it’ll jump or bounce between feeding and becoming stuck. Those periods where the wire is stuck create the perfect opportunity for the arc to burnback.

A bad grounding

If your earth clamp loses contact, the voltage will drop, but the wire will keep feeding, which causes burnback.

Wrong contact tip size

If you’re using a contact tip that’s too small, your wire is going to stick and drag through the opening. If the tip is too big, the wire has space to rattle around in it. Either way, you end up with poor conductivity and a recipe for burnback.

Damaged or wrong liner

In the same vein as the contact tip, if your liner isn’t the same size as your filler wire, it’s going to drag or be loose. The other issue with liners is that they can become damaged, kinked, or be cut too short. All these things cause wire feeding issues, which can lead to burnback.

Having the burnback control turned up too high

If you have an adjustable burnback setting on your welder and you left it set to the max, you’ll likely be flying through contact tips.

How to Prevent Burnback

The good news is that there are some easy changes you can make to prevent burnback.

First, check your settings

Your voltage and wire speed work hand in hand, so your wire feed speed should be fast enough to keep up with your heat. If you’re not sure where to start, every UNIMIG MIG welder (except the VIPER 120) comes with a settings chart in the door of the machine. The recommended settings are a great starting point for a wire feed speed that’ll match the voltage.

Second, use the correct consumables

The state of your consumables will dictate the state of your weld, so get the right ones. Your contact tip and liner should match your wire size, and all of it should be clean. Anything less, and you’re going to have problems.

Third, watch your wire tension

It seems like such a small issue, but wire that isn’t tensioned correctly can cause a lot of problems. The wire should feed smoothly, but it shouldn’t be so loose that it slips. For more on loading a wire spool, check out our Ultimate Guide to MIG Welding, or watch our video on how to tension your wire.

Fourth, get a good earth

Having a good ground is essential for any weld. The earth clamp completes your electrical circuit; without it, the machine won’t arc. That’s why you need to make sure your clamp has been attached to clean, bare metal, and it isn’t going to be bumped or moved.

Fifth, maintain your torch distance

For most MIG welding, your wire should stick out of your torch nozzle by roughly 1cm. That means your torch should be at least 1cm away from the joint. Too far away and you’ll get excessive spatter, too close and you’ll weld your contact tip.

Sixth, if you have an adjustable burnback control, adjust it.

Don’t leave your burnback set all the way on or all the way off. Neither of those is going to be ideal for most welds. Somewhere in the middle will work well and leave the right amount of wire on most metals and applications.

Burnback Controls

The burnback control on a MIG welder is used to set how far the wire will burn back once the torch trigger has been released.

If a machine didn’t have any burnback, the filler wire would stick to the weld when you released the torch trigger. The arc would stop at the same time as everything else, leaving your wire where it was – in the weld joint.

That’s where the burnback comes in. It allows the wire to remain electrically charged for a brief moment, meaning you don’t have to cut it free after every weld.

Even if you don’t have an adjustable setting, that doesn’t mean the machine doesn’t have any burnback. It just means that it has a built-in burnback amount.

The burnback controls on a UNIMIG welder can be adjusted from 1-10. 1 would be almost none, and 10 would be the max amount.

Setting your machine to 1 and having no burnback means you run the risk of the wire sticking out too far and becoming stuck in the weld.

Setting your machine to 10 and having the max burnback means you’re probably going to end up self-inflicting the actual welding problem of burnback.

We recommend setting your burnback to 5, or in the middle range, for the best results.

What you set your burnback controls to comes down mostly to personal preference. How far do you want your wire to stick out of the torch when you stop welding? If the answer is a lot, turn your burnback down. If the answer is not a lot, turn the burnback up.

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You’ve also got to weld in one of the more difficult positions: vertical up. With a bit of practice and the right settings, though, you can be pipe welding in no time.

Prep

When it comes to how it’s prepped, metal thickness is key. If you have a really thin pipe, it won’t need any prep. If it’s a really thick pipe, then you’re going to need to bevel your edges.

Bevelling the edges helps with penetration because it gives the weld somewhere to go that isn’t over and down the side of your pipe. You’re creating a groove that will give you more penetration and a stronger weld once filled.

On top of bevelling, you also need to leave a gap between the pieces, called a ‘root gap’, which will be filled with the first weld (‘root run’). You don’t want to make the gap so large you can’t fill it without issue, though.

Your root run should be the only pass that fills the gap and penetrates the backside. Every pass after that is simply filling the groove.

If you’re cutting your pipe to size with a grinder, saw, or plasma cutter, you’re probably going to have to clean it up. The inside and outside edges aren’t going to be smooth, so you’ll need to remove any burs or excess metal from it before you can bevel it.

Then there’s your standard metal prep, removing any dirt, rust, mill scale, oil and fluids before you can tack your weld.

Tacks

There are a couple of different ways that you can tack your pipe together.

You could put 4 tacks in, thinking of a clock and placing one at 12, 3, 6 and 9.

You could place 3 tacks on your pipe, at 8, 12, and 4 (clock hands) and leave the bottom open.

You can tack your pipe whichever way works best for you, and a bigger pipe will probably need more tacks to hold it than a small one. Just keep in mind that you need to tie your tacks into the final weld, so the more tacks you have, the more grinding or weld manipulation you’re going to have later.

You can’t skip them, though. Tacks aren’t just used to keep the two pieces joined. They’re also used to maintain the gap between the two all the way around.

The more tacks, the better (in most cases), because your root gap will try and close if nothing is holding it open while you weld. If your gap is uneven, there’s a good chance your pipes not going to be straight.

Positions

There are four different positions that are used to classify a type of pipe weld. These positions are mainly used to describe the angle and available movement of the pipe that’s being welded.

1G: The 1G position is where the pipe is laying horizontal and isn’t attached to anything else. You can rotate it and move it however you’d like to make welding it as comfortable as possible. This position is probably the easiest, but definitely the least common in you’re on a worksite.

2G: The 2G position is where the pipe is stood on its base (vertical) and is fixed to its position, so it can’t be moved or rotated.

5G: The 5G position is where the pipe is laying horizontal (like 1G) and is fixed to its position. This is where welding can get tricky, as you might have to work at some weird angles to get all the way around the pipe.

6G: The 6G position is where the pipe is laying at a 45° angle and is fixed to its position. 6G is considered the hardest position to weld because of the pipe’s angle and the inability to rotate it.

If you’re welding at home for fun, using these for distinction probably isn’t going to matter too much, but if you’re looking to make a career out of welding pipes, then you’ll need to know them.

Making The Weld

The goal with pipe welding is to start at the bottom and weld all the way up to the top. So, vertical up. If you can do your root run in two goes (all the up the left and then all the way up the right), that would be ideal.

Obviously, this is more realistic on smaller pipes, and if you’re stick welding a large pipe, you could run out of electrode before you get to the top.

Breaking your pipe into small sections works just as well and lets you reposition easier. Just remember that you’ll need to tie the end of the last weld into the start of the new one every time you stop.

Getting everything tied in is important because the points where you’ve stopped and then restarted are considered weak points. Tying the weld together helps to eliminate that weakness.

When it comes to pipe, you’re going to be putting down a root run. The root run is the first pass, which will penetrate all the way through to the backside. Then you’ll do a hot/fill pass (or several) to fill the joint. Finally, you’ll do a cap pass, which will leave you with a rounded top to your weld to tie it to the edges of the actual pipe metal.

Your settings will generally change between passes. You’ll want to run hotter on your root run than you will on your fill passes because you need to penetrate all the way through. The difference, though, will only be a few amps.  

Quick tip: Let your pipe cool down between passes. Preheated metal will react to your settings differently than cool metal does.

If you end up with too much filler in your fill pass, you can grind it down so that your cap will fit.

Having a high cap on your pipe is fine, but it definitely looks better if it’s almost flush. Plus, if you’re planning on cleaning the weld up (grinding it flush), having a high cap means more metal to remove. An almost flush cap is better and means less work later, so try not to overfill in the first place.

Technique

Whether you TIG, MIG or stick weld your pipe, the technique is the same: vertical up. Doesn’t matter if you’re doing your root pass, a fill pass, or you’re putting your cap on. You’ll be going vertical up.

When you weld vertical up on your pipe, you need to watch your torch angle. You want to be working from the bottom of the pipe upwards, right? Let’s think about our pipe as a clock again. You want to start at 6 and work your way up to 12. Your torch should be at roughly a 90° angle to the pipe, give or take. You want to maintain this 90° torch angle all the way up the pipe. Sometimes that means when you’re nearing the top, your arm has chicken winged into the air.

If you don’t move the torch with the weld, you’re going to end up pushing from parallel to the pipe by the time you get to the middle. If you’re flat up against the weld, you’re losing almost all of your shielding gas. Plus, it makes things spray everywhere, and the pool is just harder to control.

Maintaining your torch angle is one reason pipe welding can be so difficult: it’s like a full-body contortion.

MIG Welding

Vertical up can be kind of tricky, even on flat plates, because you’re fighting gravity as you weld. That’s where our zigzag triangle (like a Christmas tree) shape comes in. 

By manipulating your torch in a zigzag, you can be sure both sides of the base metal are being melted into. It’s great for your root pass, as it improves the penetration, and you can be pretty sure your weld is going all the way through.

The zigzag also gives you more control over the arc and helps distribute the heat evenly, keeping the filler metal where it’s meant to be.

TIG Welding

Vertical up with TIG isn’t any different to any other position. You’ll still be laying the filler wire into the gap. If your gap is quite wide, you can do a slight weave to melt the rod into both edges.

If you’re TIG welding, you can also ‘walk the cup’. Simply rock your torch in a zigzag motion, diagonally up side to side to walk the cup. It should look as though the sides of your cup are taking a walk, the right side takes a step forward, then the left side, and so on.

While your cup is ‘walking’, your filler rod is held so that it is hovering in the gap and is being melted in by the heat from the electrode. At no point should you dab it in.

You can only walk the cup with TIG, and if you choose to weld your pipe like this, it still needs to be done vertical up.

Stick Welding

Vertical up when stick welding can be hard to control, especially with the wrong settings. Getting your settings right on stick is important for the root run, so you don’t burn through while still getting proper penetration.

Unlike a normal stick weld, you want to push the electrode along the root gap to fill it. You can’t go too crazy with the weld manipulation, as you’ll just trap slag in your weld when it cools. However, you can do a slight weave between the two pieces on your root run if the gap is a bit big.

If you’re running filler beads, just push in a straight line. You’ll need more than one anyway to fill the groove.  

Purging

To purge a pipe, you need to block both ends so that air can no longer get in. There are specific rubber purging caps that you can get that come with holes in the centre that allow the purging gas to enter. Otherwise, you can use foil to block your pipe (glad wrap is too weak to hold on), but you’ll need to make your own vents.

The vents are essential for two reasons. First, you need a way to insert the gas hose. Second, once you’ve filled the inside with gas, the excess needs a way to escape. If you don’t leave a space for the excess gas, it’ll make its own, usually in your weld.

Once your pipe is sealed, you can add gas to the inside. This creates an atmosphere inside your pipe that works the same way as your shielding gas on a MIG or TIG torch. It keeps contaminants out and protects the backside of the weld.

Purging is done to keep the inside of the pipe free of oxygen, safe from contaminants and clean. How wide your pipe is and what the pipe will be used for will generally determine whether you need to purge the pipe.

If it’s a small pipe, it doesn’t hurt to purge regardless because you can’t get a file or grinder in to clean the weld up when you’re done, so purging keeps it clean, protected and gives it a weld bead appearance instead.

If your pipe is going into a high pressure or food usage, it needs to be purged to meet the sanitary conditions.

Testing The Weld

If you’ve got spare bits of pipe that you can practice with, that’s great, and you can go ahead and cut a section out to look at the weld. If you’re working onsite, your boss will probably get really upset if you cut open your weld to check it.

If it’s not a critical weld, you can go ahead and eyeball it. For the most part, you can see external defects like porosity. Unfortunately, just checking the outside of your weld isn’t the most reliable, considering you can’t see if there are internal issues. Don’t rely solely on it for important welds (like food and infrastructure).

There are more reliable ways to test a weld, like liquid dyes or an x-ray.

You can get liquid dyes that are sprayed or brushed onto a weld to make surface cracks and other issues visible to the naked eye, that might have otherwise been missed. While it is more reliable, a dye still can’t check the inside of a weld. That’s where an x-ray comes in.

A weld x-ray is pretty much the same thing as going to the doctors and getting an x-ray for a bone. That means it also comes with the potential dangers of a normal x-ray. They’re done by professionals trained to use the equipment, so if you’re working on a project at home, you’re not going to have this option.

Fixing A Weld

If something goes wrong and you end up with a defect somewhere in the weld, there’s good news. You don’t have to get rid of the entire weld. Well, you will if the whole thing has defects.

If only a section of your weld has failed, you only need to remove that part of it. Grab your grinder and grind away the faulty part of the weld. Once it’s been ground out, just redo the weld, remembering to tie it in on both sides. To tie it in properly, it’s not a bad idea to feather out the weld on either side.

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Changing the Torch Head

The best part about our replaceable torch heads is that it’s super easy to swap between the T2 and a standard head. Here’s how:

1. Unscrew the 6 small screws on the T2 torch. With the screws removed, the outer plastic on the handle should be easy to pull off.
2. Using a Stanley knife, cut the shrink sleeve off, revealing the nut that holds the torch head in place.
3. Grab two 12mm spanners, and twisting in opposite directions, loosen the torch head.
4. Remove the T2 torch head and swap it for a standard torch head.
5. Tighten the new torch head using the 12mm spanners.
6. Reassemble the torch handle, returning all the screws to their places.

And you’re done! Now you’ve got a torch head (size 17 or 26) that you can attach your standard consumables to. The torch consumables are assembled on the torch the same way as they normally would be.

Not only is swapping parts a breeze, but the replaceable heads are flexi-heads as well. So, they’re just as versatile as our T2 head.

If you ever want to swap back to our long-lasting, high-performance Arc Torchology consumables, just repeat the process. You can switch between the T2 head and a standard head in a matter of minutes.

Check out the T2 TIG Torch Head Replacements here

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1. Clean & prep your metal

MIG welding, when it comes to your metal preparation, is not that forgiving. MIG just generally can’t handle anything but clean metal, and while it can technically burn through contaminants, most of the stuff it’s ‘burnt through’ ends up trapped in the actual weld.

That’s why cleaning any paint, oil, rust (some surface rust can be ok) or otherwise off the surface is going to give you the best results.

If you’re planning on welding pieces together that have been hand-cut, make sure all your edges are smooth and dressed. If you’ve used a plasma cutter or oxy-acetylene or anything similar to cut your metal, it’s pretty likely that where it’s been cut isn’t the smoothest.

Grinding and dressing the edges is a good idea, especially with thin sheet metals, because frayed edges make burning through more likely, due to the gaps in the joint.

2. Hold the torch with both hands

You can MIG weld with one hand. You only need to hold the trigger down to run a bead along the joint. How good is a one-handed weld going to be, though?

No matter how long you’ve been welding or how good you are at it, two hands are always going to be better than one. One hand holds the torch body and pulls the trigger, and the other rests under the torch neck.

A hand under the torch neck provides you with a good stabiliser to prop against, so you can just glide along the joint at the exact same height and distance the whole way.

No wobbling up and down, no pulling the gun too far or pushing it in too close. It’ll be just right. Not to mention the added bonus of your second hand bearing some of the weight of the torch.

Don’t worry about how close your hand is going to be to the weld pool. Most MIG gloves are thick and heavy-duty. Your hands might get warm and sweaty, but they shouldn’t burn.

3. Push or Pull?

Should you push, or should you pull? It depends on the type of wire you’re using.

Does it make a difference? In short, yes. Our rule of thumb is if you’re using gas, you need to push and if you’re using gasless wire, pull.

If you drag your weld pool while you’re using gas, you’re going to lose shielding gas coverage, and you’ll be left with porosity and minimal penetration.

On the other hand, if you were to push a flux-cored wire, then you’re likely to end up trapping some of the slag inside the molten pool, which leads to contamination (slag inclusions) in your weld.

4. Earth clamp

One of the more important parts of your weld setup that sometimes gets forgotten about is the earth/ground clamp.

It’s important because, without a clamp, there’d be no weld. When connected to a metal workbench or the workpiece itself, the earth clamp completes the electric circuit and means the arc can actually ignite.

Not having a good ground will give you an unstable arc, and you’ll be able to hear and see it sputtering and popping. If your clamp or the surface it’s connected to is painted, rusted, or just dirty, it could also affect your earth.

Just making sure your earth clamp is close enough and clean enough will seriously improve your weld.

5. Stickout length

Your stickout is how far the wire comes out from the contact tip while welding. Keep it short for the best results.

The longer it is, the more resistance there’ll be in your circuit. More resistance will cause your amps to drop. Plus, the further your torch gets from the joint, the less gas coverage you’ll have. So keep it short. We recommend around a 1cm stickout.

It’s a good idea to cut the wire back to the right length for good stickout and to keep the end clean each time you finish a weld. If you leave the end of it balled, you could have a cold start with no penetration because it has to burn off that extra blob of wire beforehand.

6. Keep your consumables clean

There are a couple of small parts that make up the end of your torch. The gas diffuser, contact tip and the nozzle. All three are subject to the sparks and spatter that come from every weld, so it’s best to give them a quick clean before you start. A build-up of spatter can block your gas holes and clog your shroud, which will give you a bad weld.

7. Keep your torch lead straight

This seems pretty obvious, but don’t stand on your torch. Standing on your torch lead is going to hinder (or even completely stop) your wire feeding, and it’ll kink the wire inside. It’s best if the torch is also as straight as possible. Leaving it in tight loops or twisted can kink your wire or the liner, and it won’t feed well.

8. Anti-spatter spray

Anti-spatter spray kind of speaks for itself, but save yourself some time and coat your piece in an anti-spatter spray before you start your weld. Once you’ve finished your weld, you’ll be able to easily chip it off with a chipping hammer rather than having to grind it off to get a clean finish.

9. Vertical up

The first trick to a good vertical up weld is to make a triangle shape to keep control over the weld pool and get good fusion on both pieces all the way up.

The second trick is to turn your wire speed and voltage down from the recommended settings for a down hand butt weld.

For example, if you’re welding 6mm steel with 0.8mm wire, your settings would normally look like this: 23V (voltage) and 12m/min (wire speed). If you’re doing a vertical up with these parameters, you’ll change your settings to look like this: 19-20V and 6-7m/min. We recommend decreasing your volts by 3 or 4 and your wire speed by 5 or 6.

10. Make your MIG weld look like a TIG weld

To get a good MIG weld, all you need to do is push the torch in a straight line, which is the proper method. However, the end product isn’t always the most aesthetically pleasing weld you’ve ever seen. If your weld will be somewhere that people can see it, you might want to spruce it up a bit.

The trademark stack of dimes look that TIG is so well known for is achievable with MIG with a few simple techniques and a lot of practice.

Cursive E

Halfmoon

Backstep

Please note these diagrams are to demonstrate tip movements, not speed of weld. That will depend entirely on your situation and settings.

All three of these methods mean that you step back into the weld pool, which creates the raised back edge. If you can repeat each loop, step, curve for the exact same amount every time (hence all the practice), you can create the ‘stacked dime’ effect without a TIG machine.

Keep in mind NONE of these are possible if you’re using gasless flux-cored wire in your machine. Dipping back into your weld pool will trap the protective slag in the weld, and it’s going to leave slag inclusions. You’ll have to stick to the necessary dragging in a straight line technique with flux.

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They both cut through metal, yes, but that’s about where the similarities end. In reality, they’re two totally different processes, and each has its pros and cons.

What is Oxy Acetylene Cutting?

Oxy cutting is a method of cutting through ferrous metals using gas to produce a flame. It uses a mixture of oxygen and acetylene (or propane, natural gas, LPG) to rapidly oxidise the metal and cut through it.

Oxy acetylene will only work on metal that contains iron because the cutting is done by oxidisation. The metal needs to be preheated before it is cut, although it’s done with the same torch.

What is Plasma Cutting?

Plasma is a super-heated column of gas. Plasma cutting (plasma arc cutting) is a melting process that uses plasma and an outside power source. It creates an electric arc between the electrode (which is in the torch) and the metal being cut, melting and ejecting it from the cut.

The plasma beam is usually formed with compressed air, although you can use compressed hydrogen mixtures.

Plasma can cut through anything electrically conductive. That means it will work on steel, stainless steel and aluminium, as well as less commonly used metals like copper or bronze.

Oxy cutting vs Plasma cutting

There are quite a few differences between the two methods, from gas requirements to preheating, travel speed, and portability. So, which is going to work best for you?

PROS

CONS

The pros and cons further explained

Plasma Cutting Pros:

• Plasma will cut through all types of metal, ferrous and non-ferrous, so it’ll work on almost anything you need to cut.
• Plasma doesn’t require any preheating; you can just start cutting your metal as soon as the torch is on.
• You’ll only need an air compressor to connect to your machine to create the plasma. Some plasma cutters (like the RAZOR CUT 40 AIR) come with a built-in air compressor, so it may be a bit heavier than a standard machine, but you don’t need to go out and anything except the machine.
• The torch is ignited and extinguished with the touch of a button instantly, so it’s easier to use, and there’s no need to rotate valves trying to adjust to the gas levels to get the correct flame.
• There is a lot less kerf and dross involved, it’s a much cleaner cut, and any excess metal that remains afterwards can be easily removed with a chipping hammer.
• Plasma machines are generally lightweight (the RAZOR CUT 45 is only 10kg!), especially the smaller, more commonly used ones, so they’re easy to carry around.
• You can cut a lot faster with plasma, especially on really thin material, thanks to not needing to preheat.
• Plasma is a lot safer, with no open flame, and once it stops making contact with metal, it will stop completely after a few seconds. You can put the torch down and forget about it without worrying about burning anything down.

Plasma Cutting Cons:

• The max cut thickness, depending on the machine, can be less. The VIPER CUT 30 Mk II, which has a max amperage of 30, can only cut (cleanly) through 12mm steel. On the other hand, the RAZOR CUT 80, which has a max amperage of 80, can cut through 30mm steel.
• The machine and air compressor require a power source (though these days, power points aren’t too hard to find).

Oxy Cutting Pros:

• It doesn’t need a power source, with only a torch and two gas tanks. That means it’s often more favourable if you’re working somewhere remote and there isn’t any access to power.
• It’s good for thick metal, from 25mm (1 inch) up to roughly 300mm (12 inches), as you aren’t limited by amperage. You’ll just have to travel slowly along thick metal to make sure it cuts all the way through. Oxy torches come with a range of tip sizes for different metal thicknesses that screw on and off easily.
• Oxy torches can be used for more than just cutting. You can also weld, gouge, braze, heat and solder with them without switching machines (you’ll need to switch tips, though).

Oxy Cutting Cons:

• Oxy acetylene will only cut ferrous metals, so its only application is steel.
• The metal needs to be preheated before you can begin cutting, especially on thick sections. The preheating is done with the same torch, but it’s extra time standing and waiting to be ready.
• It requires two types of gas – oxygen and a fuel, usually acetylene (as it burns the hottest). That means purchasing two gases and refilling them. Not to mention they’re highly flammable.
• The setup is longer, despite less ‘equipment’ involved. The gas tanks need to be set to the correct flow rates, and the flame on the torch needs to be adjusted to a ‘neutral’ one each time.
• The torch has to be lit manually with a flint lighter and can only be turned off via the valves on the torch. It’s slower and a lot less safe.
• It’s incredibly messy. As well as a shower of sparks, oxy cutting leaves a lot of the molten metal to drip and sit on the bottom/inside of whatever you’re cutting, which has to be ground off later. It’s like spatter when you’re welding taken to the extreme.

Oxy cutting was the original method of metal cutting, but with new technology, plasma cutting has caught right up, and in a lot of ways, overtaken it.

If you’re going to be working on really thick steel, then an oxy cutter might still be better for you, but for almost everything else, you’ll be better off with a plasma cutter.

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So, which one is going to work best for what you’ve got planned?

Metal Inert Gas (MIG) Welding

Metal Inert Gas (MIG) welding is a welding process in which an electric arc is created between the workpiece and a solid wire. The wire (filler metal) is continuously fed through the welding machine and into the weld pool to form the weld.

The process of MIG welding is semi-automatic, as the machine does all the wire feeding for you, which is why MIG welding is considered one of the easiest types of welding to learn.

MIG welding is done with a MIG torch for mild and stainless steel and a spool gun for aluminium. A wire spool is attached inside the machine and fed through rollers into the torch liner and then out of the torch automatically, so once it’s set up, all you need to worry about is the settings.

There are only two settings on a MIG machine: voltage and wire feed speed. It’s relatively straightforward to set up, and because it’s as easy as aiming the gun in the weld joint and pulling the trigger, it’s the fastest way to weld.

The main downside to MIG welding is that it’s not very good in outside or windy conditions, as it’s a gas-shielded method. However, there’s good news. You can MIG weld with gasless wire as well.

MIG welding is used for a lot of fabrication work as it works on thin and thick materials, so it’s very versatile. Some common applications are things like frames, trailers, car panels and general fabrication. It is also commonly used for DIY and hobby projects because it is so easy to learn.

Flux-Cored Arc Welding (FCAW)

Flux-cored arc welding (FCAW) or gasless MIG, is set up and done almost exactly the same way as gas MIG, though there are a few differences.

Rather than a solid wire, a hollow wire that contains flux, which produces a protective layer of slag on the finished weld. The slag layer means that a shielding gas isn’t needed for flux-cored welding. You can also get gas-shielded flux-cored wire, but that’s generally only used for certain heavy-duty welds.

One of the main downsides to choosing flux-cored is that it can’t weld quite as thin material as standard MIG, and it’s not recommended for sheet metal or car panels.

FCAW welding is almost exclusively used on outdoor applications, as it eliminates problems like wind blowing away shielding gas. It’s also more forgiving on dirty or rusty surfaces, so any repairs or fabrication, like fences and gates, are some of the more popular uses of gasless MIG.  

Check out our Gas vs Gasless post for more on the differences between gas MIG and gasless MIG.

Tungsten Inert Gas (TIG) Welding

Tungsten Inert Gas (TIG) welding is the process in which an arc is formed between a tungsten electrode and the workpiece to join the metals together. A filler rod is often fed into the weld pool to create a weld. Shielding gas is required to protect the weld from atmospheric contaminants.

TIG welding is considered the most challenging type of welding to learn because of all the variables involved and the coordination needed to feed the filler into the weld.

On top of learning how to make a proper weld, TIG welding is also more complicated because of the number of settings that can be adjusted. Plus, the more features the machine has the more settings that can be changed.

For example, the VIPER 180 AC/DC Mk II TIG Welder only has the standard set of pyramid settings (pre and post gas, up and down slope, peak amps, etc.).

In comparison, the RAZOR 320 AC/DC TIG/Stick Welder has some added features, like being able to change the AC waveforms as well as being capable of mixed arc welding. These features come with their own settings on top of all the normal ones the machine comes with.

TIG welding uses a non-consumable tungsten electrode, of which there are several different types, all with their pros and cons, which allows TIG welding to be the most versatile when it comes to metal types.

Once you’ve gotten the hang of TIG, you can also introduce a foot pedal to adjust the amps manually while you weld, rather than being limited to whatever you’ve set on the machine.

Despite how complicated it is and how long it takes to master, TIG is popular because of how much you can do with it. It works the best on thin sheet metals and aluminium, so it’s a great choice for most automotive work.

It’s not often used for production work, however, as it is quite a slow process. It’s also the most aesthetically pleasing, with its stacked dimes look, so it’s used on welds that will be seen or for artworks.

Manual Metal Arc (MMA) Welding

Manual Metal Arc (MMA) welding or ‘stick welding’ is the process in which a power source is used to create an electric arc between a flux covered electrode and the workpiece. To ignite an arc the electrode is struck against the metal and then melted into the joint to create the weld.

The flux covering acts as a protective layer for your weld, so no protective gas is needed. The protective coating on the electrode leaves behind a topcoat on your weld known as ‘slag’, which needs to be removed to expose a clean weld.

In some ways, stick welding is the easiest to set up, as there’s not much to it. All you need is an electrode, an electrode holder, and to set the amps on the machine.

On the other hand, it can take some practice to strike an arc in one go (and some electrodes are harder than others to start), and adjusting to the electrode melting away can be difficult. You have to move with the electrode, otherwise, your arc will get too long, and it’ll go out, or you could stick it to the workpiece instead.

Thanks to its simplicity, almost every welding machine can also stick weld, but you can get machines that are dedicated stick welders, which are super easy to work because their only setting is an amperage knob.

Stick welding is most commonly used for construction and on structural builds, as they’re the most capable when it comes to thick material. They’re also the most portable welding machine, so they’re great for on-site work.

The downsides to stick welding are that you can’t weld on very thin material, it can’t weld aluminium, and there’s usually more cleanup to do at the end of a weld.

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Gas-shielded MIG

Gas-shielded welding is the standard, run-of-the-mill MIG welding that is usually what everyone is talking about when they talk about MIG. It requires an external gas (generally an ArCO2 mix) to protect the weld pool from the atmosphere and other outside contaminants.

Gasless MIG

To weld gasless, you need to use the specific flux-cored filler wire required. It’s kind of like MIG welding a stick electrode because a protective slag layer forms over the metal to shield it from contaminants. It can be argued that gasless welding isn’t technically gasless.

As the flux inside the wire melts, it releases its own vapours (also known as gases) to protect the pool, which bubbles to the surface to form slag over the weld. That’s why gasless welding is also known as ‘self-shielded’ welding because there’s no gas cylinder needed.

What are the Differences?

Wire Types

The flux-cored wire spools that are used are loaded into a MIG machine in the same way that a standard MIG spool is, and they’re welded the same way (mostly).

The main difference between how you weld with gas or gasless is whether or not you’re pushing or pulling the gun. If it’s gas, you push. If it’s gasless, you drag.

Gasless is generally only used on mild steel because flux-cored MIG wires don’t really come in other kinds of metal. Mild steel is by far the most common when it comes to flux-cored wires. There are flux-cored stainless steel MIG wires, but they’re not as easy to come by.

Flux-cored wires need their own drive roller as well. The knurled (F groove) rollers come with serrated edges, so they can grip and feed the softer wire through the torch without crushing it. Make sure to swap the drive rollers when you switch wire spools.

Polarity

Gas and gasless use different polarities. If you’re welding with gas, then you’ll need to set your machine to DCEP (positive polarity). If you’re welding with gasless, you’ll need to set your machine to DCEN (negative polarity).

Fumes

MIG welding produces smoke, whether it’s gasless or not. It’s simply a question of which one is worse. The answer? Gasless.

Gasless (flux-cored) welding creates a lot more fumes than when using a shielding gas, thanks to all the things in the flux that work to protect the weld. That’s why gasless welding is much better for outdoor use.

The smoke and fumes that come off a gasless MIG weld are toxic, with short term effects like dizziness and nausea and long-term effects that are more serious.

If you’re inside, you’ll need a respirator or proper ventilation, with an actual ventilator or with a fan to blow it away.

Outside/Inside

Gasless welding isn’t affected by air movement. There’s no shielding gas being blown away by the wind, so it’s perfect for when you need to work outdoors. Not to mention that being outdoors is a great way to ventilate all the smoke that you want to avoid breathing in.

You absolutely can weld outdoors with the gas process, but it’s recommended that some sort of screen or wind shield is put up. The screens will keep any wind or otherwise out, so your shielding gas isn’t blown away, and your weld remains contaminant free.

Portability

Gasless uses less equipment because you don’t need a gas cylinder, so it’s lighter and more portable because only the machine is required. Keep in mind every MIG welder needs a power source, regardless of if you’ve got a gas or gasless machine.

Metal Prep

Just like stick welding, gasless wire can weld through paint and rust, for the most part. But, just because you can, doesn’t mean you necessarily should. If you’re welding with gas or gasless, clean metal is the best metal.

Clean Up

Also just like stick welding, the flux-cored wire leaves a layer of slag on top to protect the weld, which needs to be removed.

Gasless welding is prone to more spatter too, which adds to your overall clean up time after a weld. That’s where your handy anti-spatter spray comes in, so the bits of spatter can be chipped off quickly.

Gas-shielded Flux Core

There is a third kind of MIG wire that you can get: gas-shielded flux core. Otherwise known as ‘dual shielded’, it forms a slag covering and requires gas to protect it.

It’s a much more specialised type of MIG welding, and if you’re a home hobbyist, you won’t really need to bother with it.

The ‘dual shielding’ makes it great for structural welding, with increased weld deposition rates, high penetration and a super protected weld.

However, it also comes with some of the cons of gas and flux-cored wires. It produces a lot of fumes, there’s extra clean up of slag once you’re done, and you’ll still need to purchase a gas cylinder, as it adds that extra layer of protection to the weld pool.

Which One Should You Use?

There are pros and cons to both gas and gasless MIG welding, so which process you choose is going to depend on what welding work you’re looking to do. There are a couple of things that should be considered when debating between the two. 

Your location ­– where are you going to be welding? 

If you’re going to be welding outside, especially if it’s farm work like repairing a fence and you’re somewhere kind of remote, gasless is the way to go.

If you’re going to be inside or out of the elements, you’ll want gas.

Your metal – what metal type and thickness are you welding?

Gasless welding has a few restrictions, so if you’re working with stainless and aluminium, then you’ll need gas-shielded MIG.

Portability – do you need to be portable?

Is trying to move a gas cylinder practical for where you’ll be welding? If your answer was no, go gasless.

Cost – what’s your budget?

Flux-cored wire spools are generally more expensive than their solid wire counterparts, but overall, it’s cheaper because you don’t have to pay for a gas cylinder on top of the cost of the wire spool.

Every UNIMIG MIG welder can do gas and gasless MIG in the same machine. You’ll just need to change the torch polarity and have the correct filler wire.

That means you’ll be able to run gas-shielded MIG, flux-cored MIG and gas-shielded flux core MIG wires on one machine. Having a welder with the ability to run both gas and gasless applications makes your choice easier. You won’t be locked into a single method, and you can pick and choose depending on each individual application.

Check out UNIMIG’s range of Gas & Gasless MIG Welders

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A foot pedal, or foot control, can be used to control the amperage of your welder while you’re welding. Weld getting too hot? Ease off the pedal and lower the amps, which lets the weld cool. The foot pedal gives you complete control without having to stop in the middle of a weld and readjust.

They can only be used while TIG welding, as stick welding uses an electrode holder rather than a torch and MIG’s amperage is dictated by the wire feed speed. Considering TIG often requires more control over low amps on thin metals, it’s not a big deal.

Why do I need a foot pedal?

When you’re first starting out, TIG welding, in general, can seem pretty daunting. Especially if you’ve gotten yourself a TIG dedicated welding machine that has a hundred little lights and options and settings.

Okay, there aren’t that many, but that little pyramid of weld parameters on your TIG welder can be kind of overwhelming to start with.

If TIG is already a handful, why on earth would you want to add another variable into the mix with a foot pedal?

A foot control gives extra control over the amps (heat) of your weld, thanks to being adjustable mid-weld rather than being static throughout. The added control means a better weld. Plus, it can be more comfortable.

The welder’s comfort can make a world of difference to how a weld turns out. It’s a lot easier to hold a pedal down with your foot than it is to constantly hold a button down with your finger.

How is it set up?

The setup for a foot pedal is pretty simple, thanks to having just one cord and one settings knob.

1. Plug your cord into the front of the machine.

The actual connection is a pin plug setup, so make sure that the pin plug number on your foot pedal and the machine match up. You can get adapters to connect different pin plugs.

2. Set the peak amps on the machine.

All of your settings are set on the machine, the same way they’d be set if you were using a torch. The peak amps you select on the machine will translate to the pedal.

3. Switch to remote mode.

In order to use the foot pedal’s controls, the machine needs to be placed in Remote mode. To do this, just hold the pedal down for 5 seconds and until the Remote green light appears.

4. Make sure the machine is in 2T.

The foot pedal won’t work in 4T. Because you have to hold the pedal in to weld, having it in a mode where you let go of the trigger doesn’t work.

Now your pedal is set up and ready to use.

Pressing the pedal in will start the arc, the same way pressing the button on a High Frequency torch does. Once the foot pedal is pressed, the machine’s screen will read what amps you are currently at.

If the pedal is all the way down, it will read the peak amps you set the machine to. Anything less than fully pressed, and it’ll show you what the amps you are sitting at are. As you adjust your foot pressure, the screen will adjust its reading to reflect the new amperage amount.

It may take some time to get used to how it works and how far back you can release the pedal before you’re lowered too far. The pedal comes with an adjustable knob on the side, which allows you to control the max amps from the foot pedal – to a certain extent. With your pedal knob set at ‘max’, it will only go as high as what the peak amps are set to on the machine.

Say you set the peak amps on the machine to 150 and have the pedal knob set to max. Holding it pressed all the way down, it’ll weld at 150 amps.

If you were to adjust the knob to halfway, it would then only weld as high as 75 amps when pressed all the way down. However, you can’t exceed whatever amperage you have set on the machine with the foot pedal. It has to be increased the way all your other settings do, using the interface on the machine.

Pulse welding with a foot pedal

One of the best things about having a foot pedal and control over your amps is you can manually pulse weld. If you don’t have a TIG machine that comes with a pulse option, just do it yourself.

Press and release, press and release, at a steady pace, and you’re pulse welding. By flooring it, you reach the peak amps. Then, by backing off, you lower to the base amps.

It does take some practice to get the timing and pressure consistent, though. Being able to pulse is incredibly useful if you’re welding really thin metals, and you adjust your pulsing on the fly by doing it with a foot pedal.

Limitations of a foot pedal

You can’t use a foot pedal if you don’t have a machine that can support it. For example, UNIMIG multi-process machines like the VIPER 185 doesn’t support the use of a foot pedal.

Foot pedals are great for giving a welder that added bit of control over every weld. Just be sure that you have a machine that can support it.

Check out the UNIMIG TIG Welding Foot Control

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How often it pulses, what the peak amps are, what the base amps are, and how long it spends on either amp setting can all be adjusted to suit the weld you’re doing.

Pulse Frequency/Pulse Hertz

The pulse frequency or pulse hertz are the same thing: the number of pulses per second. For example, the UNIMIG AC/DC machines have a pulse frequency range of 0.5-200Hz per second. That means that 1Hz equals one pulse per second, and 50Hz is 50 pulses per second.

One pulse per second is relatively slow and easy to follow with your eyes. 30 pulses or more is pretty fast, and it’s hard to see the individual pulses. Anything between the 5-30 pulse range is painful on the eyes. It’s kind of like staring at a strobe light, which is super unpleasant to look at and really hard to concentrate on timing a weld with.

When it comes to picking how many pulses a second you want, it really depends on the application. If you’re welding thin material, then a fast pulse is usually better, and it will leave a high profile bead. If you’re welding thick material, then a slow pulse is usually better, and it will leave a low profile bead.

Pulse Percentage (%)

The pulse percentage is the amount of time spent in the peak and base amps for each pulse. If you set the percentage to 50%, that means 50% of the pulse cycle will be the peak amps, and 50% of the pulse will be the base amps.

You can adjust this either way, where 90% is almost entirely peak amps and 20% is almost no peak amps. The more time spent on the peak amps part of the pulse, the more penetration you’re going to get and vice versa.

TIG Pulse

Pulse welding with TIG is done almost the same way as standard TIG welding. There are just a few extra settings to adjust on the machine first. But, when you pulse weld with TIG, you can feed your filler rod in two ways (rather than one).

1. The first way is your standard dabbing. Depending on how many pulses a second you’ve got it set to, you can dab on the peak and pause on the base amps. If you’re only on one pulse per second, this isn’t too hard to get used to. However, if you’re welding at around 50 pulses a second, your dab time can just be consistent, as there’s not really a way to time it with the pulses because your eyes almost can’t see them anymore.
2. The second way is to just lay the wire in the joint. Now, you don’t just lay it flat and weld over it, but instead, you have the tip of your rod in the leading edge of the puddle, and you drag it down the weld, keeping it in the leading edge so that it melts in.

Both techniques work, and you can do either regardless of your pulses per second, but if you use the lay method on high pulses, you won’t get the stacked dimes look. It’s still a good, penetrative weld, but it just won’t be as aesthetically pleasing.

You can still use your foot pedal when you pulse as well. You can hold it at full throttle and have your peak amps sit at what you set them to, or you can pulse within the pulse.

What that means is if you’re pulsing along and you still believe that the weld is getting too hot, you can ease off the pedal, lowering the peak amps in the pulse. Your background (base) amps will remain the same, but the high part of your cycle will be slightly cooler.

For example, say you’ve set your machine to a peak amps of 200 and your base amps to 50. Holding the foot pedal down will leave your peak amps at 200 for the whole weld.

However, if you were to ease up on the foot pedal, your peak amps would reduce, say to 150, while your base amps would remain at 50. So, overall, the entire weld would cool as your peak amps aren’t as hot.

Then if you decided you needed more heat again, you could go back to full depression of the pedal and increase back to your original 200 amps.

MIG Pulse

There are two kinds of pulse MIG welding:

Single Pulse – Single pulse MIG is a type of spray transfer that, like TIG, alternates between the peak current and the background current.

MIG pulsing is generally spatter free because the wire never actually touches the weld.  Droplets of metal are ‘sprayed’ into the weld on the peak part of the cycle.

The background current of the pulse cycle isn’t hot enough to transfer metal. It simply maintains the arc. It produces all the benefits of spray transfer (speed, no spatter, deep penetration) without all the excess heat.

Single pulse MIG welding sounds similar to an AC TIG weld, with a constant high pitched buzzing.

Double Pulse – Double pulse is two pulses that happen simultaneously.

The first pulse is your standard (see: single) pulse with a peak amp and a base amp.

The second pulse, which doesn’t transfer any wire, turns the first pulse on and off in its cycle. During this second pulse, the arc remains on, but the temperature is so low there is no welding happening.

When the second pulse is ‘on’, the first pulse takes over (turning on) and alternates between the peak amps and base amps, creating the weld the same way a single pulse does. When the second pulse is ‘off’, nothing is happening.

The ‘off’ part of the second pulse can be adjusted to be hotter or colder, but its purpose is to give the base material a moment to cool. In order to make the most out of a double pulse, leaving the base of this cycle low is recommended.

Double pulse MIG welding is a cooler procedure as there’s even more downtime between the high amperage moments, so you need more amps in the peak to get full penetration.

It’s great for a good-looking weld because it creates the stacked dime effect of TIG with a MIG machine and no effort from the operator. It has an on-and-off high pitched buzzing that accompanies it.

These processes can either be synergic, in which the welder makes your life really easy and picks all the best settings for you. Or, it can be non-synergic, and you’ll have to input every value yourself (which, let’s be honest, takes some serious trial and error, especially when it comes to the double pulse).

While the arc itself doesn’t look like it’s pulsing, it definitely sounds different to a normal MIG weld, whether you single or double pulse.

Despite it sounding convoluted and confusing, making the actual weld while pulse welding with MIG is just like standard MIG welding. Once the machine is set, just press the trigger on your torch and weld along the joint. It does the rest for you.

Why should you pulse weld?

Pulse welding focuses the arc and keeps the bead smaller, so it stays in place. Not only is it easier to control, but you still get full penetration.

When you enter the base amps part of the pulse cycle, the puddle freezes, and that moment of cool helps the weld to sit down flat. The longer you spend in the background amps, the better the ‘puddle freeze’, which is what creates the stacked dimes look.

Pulse welding also totally eliminates spatter, so you won’t have any post-weld clean up.

When should you pulse weld?

Out of position welding

The cooling of the puddle that keeps it small means it’s not as likely to drip. If you’re welding out of position, then using the pulse will keep the weld where it’s meant to be, rather than on you.

Sheet metal

Pulse welding is a cooler process than standard welding because of the moments of low amperage. With less heat in the metal, you get less distortion, which is perfect for thin materials.

Different metal thicknesses

Like with welding out of position, the pulses help hold the weld puddle exactly where you want it, which makes it much easier to weld thin pieces to thick pieces. It’s especially true when welding a lap joint that’s made up of two different sizes. You don’t need to worry about the pool spilling over the top edge.

Stainless steel, aluminium and other high thermal conductivity metals

Not only is pulsing good for keeping the distortion out of sheet metal, but it’s also often used with metals that are known heat sinks. The cooler welding provides all the needed penetration without having to blast the metal with too much heat.

Filling holes

Having the ability to weld without putting excess heat into the metal makes filling holes a lot easier. There’s way less chance of blowing further through a hole (or through metal in general) with the lower heat levels.

No spatter

It’s not really an issue when you’re TIG welding anyway, but reduced spatter when you’re MIG welding means less clean-up once the weld is done.

Pulse welding isn’t the only way that works with any of these applications, but it certainly makes some of the more difficult kinds of welding a lot easier.

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1. Current settings

There are two parts to the current settings: polarity and amperage. The good news is that getting the correct settings for both of these is fairly easy, given that they’re listed on the electrode’s packaging.

For example, the HYPERARC 6013 General Purpose electrodes have a recommended polarity of AC & DC+ and a current range of 90A – 130A (for the 3.2mm size).

Why is there more than one option for both? The 6013 GP’s are a more versatile electrode, so they’ll weld well on AC and DC+, which one you use is more of a personal preference. A lot of electrodes will only come with one recommended polarity setting.

In regards to the amperage, every electrode will have a range, as it will run without problems within that range, though you may need to move faster towards the higher end, or if your workpiece metal is thinner, you’ll want the lower end.

How do you know if your amps are wrong?

If you don’t have a high enough amperage, you’ll find the electrode is a lot stickier, and it’ll be difficult to strike an arc without getting stuck to the metal.

Not enough amps also means there’s not enough heat to melt the core wire. Rather than fusing it into the base piece as you weld, it’ll leave little balls of metal on the surface. You’ll also find your arc winks in and out or stutters, regardless of how close you hold your electrode.

On the flip side, if your amps are too high, you’ll find that the weld pool is incredibly fluid and hard to control (but you won’t have issues starting an arc). Too many amps will make your arc louder and will often produce way more spatter as well. It can also cause the electrode to gouge the workpiece without filling it in.

With amperage, a good place to start would be in the middle of the recommended range. If you’re not happy with the way it’s running, adjust your amps by 5-10 either up or down, depending on what is happening with the pool, arc and spatter.

You’ll also need to adjust your amps based on your position; if you’re in an overhead weld, lowering your amps by about 15% will help keep the molten metal in the joint and not on you.

UNIMIG has a guide on which amperage range to use based on workpiece thickness, so check out the free Ultimate Welding Guide.

2. Arc length

Once you’ve started an arc, the key is to maintain it. The best way to keep an arc consistent (and lit) is by holding your electrode a steady distance from the plate. In general, holding it roughly 3mm off the workpiece will give a good arc.

If your arc gets too short, then you’re going to lower your voltage and stick your electrode to the workpiece. If your arc gets too long, your voltage will increase, your puddle will widen, you’ll get more spatter, the metal can spray as the arc isn’t focused, your arc can extinguish, and you’ll also get undercut. Undercut occurs when the weld gets too wide (sometimes because of too many amps) and the base metal melts along the edges, but there is not enough filler material to fill the gap, so you are left with a groove on the toes of the weld.

When you’re first learning to stick weld, keeping your arc tight can be hard, especially considering your electrode is melting away and getting shorter as you go. It can be tricky to adapt to the movement while still making sure your arc doesn’t get longer, but proper arc length is essential.

3. Drag your weld

Always pull (or drag) your stick welds. If you try and push your electrode, all you’re going to do is trap the protective slag inside the weld pool, where it will be the opposite of protective. It’ll contaminate your weld instead.

There is only one exception to the drag rule, and that’s when running a vertical up weld. Pushing your weld up a joint is the only time you should ever push your stick weld.

4. Visibility

Just like with any kind of welding, being able to see what you’re doing is super important. How are you going to run your bead in a straight line or watch your arc distance if you can’t see?

Make sure you’re in a comfortable position where you’ll be able to watch what’s happening. Also, keep your face and helmet out of the fumes. Not only do they limit the visibility of your weld, but they’re harmful to breathe as well.

5. Clean, clean, clean

Is stick welding the most forgiving when it comes to cleanliness? Yes. Can you just weld over several millimetres of rust with it? No.

While stick welding is absolutely the most flexible when it comes to surface contaminants, even it has its limit. Cleaning your metal is going to give you the best possible weld, so take a few extra minutes to hit your material with a wire brush or a grinder. If you can’t get everything off, that’s ok, but do slow your travel speed if that’s the case. Going slower will leave more time for the gas bubbles to boil out before the slag forms.

Having clean, bare metal to attach your earth clamp to is also a priority because, without a good grounding, you’re not going to get a good weld.

6. Wet is bad

Generally, electrodes contain some moisture in them, but excessive moisture (or a totally wet electrode) is not good. If you’re using a low hydrogen electrode, then any moisture in your electrodes is a no-no.

If your arc is erratic, wandering or rough, there’s a good chance your electrode isn’t dry. Your flux will also chip off and end up in the weld pool (un-melted) which causes weld defects as well.

There are two ways you can fix this.

The first: prevention. Make sure your electrodes are stored somewhere that is dry and preferably sealed so they stay dry.

The second: an electrode oven. Not to be confused with your kitchen oven. An electrode oven will re-bake the flux coating on an electrode, evaporating any moisture and leaving them ready to weld.

7. Movement

Running a bead with your stick electrode is pretty simple; it’s a steady, straight line. For the same reason you only want to drag a weld, you don’t want to be circling over the back of your weld pool and trapping slag inside.

If your weld joint is too wide for just a single bead, make a second, third, or however many passes you need in order to properly fill it. These will all be straight lines, with a 50/50 overlap of the filler and base metal to fuse them together.

Once again, the only exception to this rule is a vertical up weld. You can rock slightly side to side so that the electrode tip makes contact with both sides of the weld joint. Don’t hover over the middle, as it will take care of itself; you just want to ensure that the bead penetrates the corner properly and you don’t get any undercut on the edges.

8. Speed

A good travel speed is a consistent one. It’s also one that doesn’t burn through your plate or leave your bead sitting on top of the metal instead of melted into it. How can you tell if you’re too fast or too slow?

If you’re moving too fast, you’ll end up with a narrow, high bead that looks like it’s sitting above the metal. That’s because it is, as there wasn’t enough time to heat the workpiece and electrode to have it melt in.

If you’re moving too slow, your puddle will get wider, but the build-up will also be higher, and you’ll have shallow penetration. That’s because instead of melting down, your puddle goes sideways instead, so you get a fat bead with no extra penetration.

9. Dry runs

Doing a test run for any weld is a good habit to pick up, but it’s especially good for stick welding.

It’s definitely better to find out before you start welding that your elbow is going to bang into the table or another corner or anything as your electrode melts.

Making sure you can move down with your electrode, and you won’t be obstructed means you won’t need any unnecessary restarts halfway through your joint because you suddenly realised you had to reposition.

You always want to be comfortable before starting your weld, and doing a dry run will ensure that you can stay comfortable.

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Which one is going to work best for you?

What’s a Spool Gun?

A spool gun is a pistol grip style gun with a compartment for a wire spool roll to be attached directly onto the gun.

The gun also comes with its own drive rollers inside the gun, so the wire can feed from the spool, through the gun and out into the weld.

The wire only has to travel the length of the gun instead of through a 4-metre torch lead, which means there are so many less places for things to go wrong.

What’s a Push-Pull Gun?

A Push-Pull gun is a pistol grip style gun with a small, second motorised wire feeder directly in the gun.

This motor works in harmony with the feeder inside the machine, and together they achieve a smooth feed as the machine pushes the wire through the torch lead and the gun pulls it through from the other end.

A Push-Pull gun is more like a standard MIG torch than a spool gun, as the wire spool is still loaded up inside the machine and fed through the machine’s rollers and into the torch lead.

Which one should I use?

Spool guns and Push-Pull guns are both operated in the same way as a regular MIG torch; hold down the button, and off you go. They’re also both designed to weld aluminium (although you can swap your drivers and use steel in them if you really want).

Spool guns and Push-Pull guns have longer torch leads than standard torches; UNIMIG spool guns come with a 6-metre torch lead, and the Push-Pull guns come with an 8-metre lead.

Despite the fact that they were made to do the same thing, there are a couple of differences to consider when you’re picking between the two.

Spool guns totally eliminate the birdnest and wire kinking problems that are the biggest issues when it comes to aluminium. You’re going to save yourself a lot of time and material if you’re not always having to fix your wire because it’s kinked in the torch or just not feeding at all.

Generally, a spool gun is the best choice for aluminium if you’re using it for smaller applications or you only weld aluminium occasionally.

They don’t come with the ability to do as many max amps as a Push-Pull gun can, so their duty cycles are lower, meaning you can’t weld very thick material.

They also only have the capability of housing 0.5/1kg spools and can be heavy, fatiguing your hands faster because of the spool you’ll be supporting. That’s why they’re recommended for shorter welds.

The spool holder on the gun makes them bulkier than other guns, so you may find it harder to get into tight spots as well, as the gun’s angle is really important for a good weld.

Push-Pull guns can withstand higher amps than a spool gun, so they can weld for longer periods of time on thicker metals.

They have a different plug to a spool gun or MIG torch, so there are not as many machines that are compatible with them. However, the machines that do have the right connection also have the higher amp ranges that the Push-Pull guns are capable of.

A Push-Pull gun, though bulky, is usually lighter and smaller than a spool gun but still heavier than a standard MIG torch. It’ll fit into small or tight spaces better than a spool gun because it doesn’t have the spool holder getting in the way.

In general, if you’re planning on doing lots of aluminium welding or welding it for long periods in one go, a Push-Pull gun is for you.

However, if you need to swap between materials often, then a Push-Pull gun can be a pain. You’ll lose all the wire still inside the gun every time you switch before finishing a spool. Push-Pull guns are also usually much more expensive than spool guns.

Check out the full range of Spool Guns and Push-Pull Guns

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1. Get a good earth

When you’re working with sheet metal, you need a good grounding, even if you’re working on part of your car. Say you’re working on fixing a front door panel; having your earth clamp attached to the boot isn’t going to help. It’s too far away.

Getting a good earth may mean grinding some paint off and clearing some metal to make it bare, but having your clamp as close to – or directly on – the metal you’re welding is going to provide the best result.

When your earth clamp is too far away or not directly touching bare metal, your arc can wander, and the weld quality plummets.

2. Backing plates

Get yourself some copper backing plates. They’re used as heat sinks, so you don’t blow holes in your metal if there’s a gap between the two pieces or if it’s super thin.

Not only are they good for absorbing some of the extra heat, but they can be easily removed once you’re done, as steel and aluminium won’t stick to copper.

Unfortunately, using a backing plate is only possible if you have access to the back of the panel, so you won’t be able to use them in every situation.

3. Keep your fit flat

If you’re working on a car, you’re probably more likely to have a body hammer, but they’re useful for more than just car panels.

Working your metal with a body hammer as you go helps to release some of the stress that’s in the metal, which reduces the warpage. You can do this on your tacks as well as the actual weld, and it helps to flatten your tacks down, so they’re easier to weld over later.

Hammering the stress out of the metal will usually flatten it back out as well, removing a lot of the warpage as you go so you can weld a mostly straight piece of metal the whole time. You don’t need to hit it too many times or beat it as hard as you can. You’re not hammering a nail, be gentle.

Be careful when hammering a MIG weld, though, as the actual weld is more brittle, and if you hit it too hard or too much, it’ll crack.

4. Metal manipulation

If your metal needs to be shaped to fit, like when you’re making a panel that needs to match the rest of the curves on the car, it has to happen before you start welding.

Sometimes the weld will pull the piece into the correct shape, but exaggerated curves or two different bends on a single panel – that kind of thing needs to be done beforehand.

5. Don’t leave holes

Like with every weld, you need to fill the entire joint. When you’re working with sheet metal for car panels, it’s even more crucial that you don’t leave any holes at all. Even a pinhole will allow moisture in.

Whenever you restart your weld, start over the end of the previous weld. That way they’re tied together, blended properly, and there’s no chance of a hole being between two welds.

Any kind of moisture in your metal is going to cause rust, which is why eliminating any potential points of entry is essential.

6. Making your welds flush

When you’ve finished welding, all you want to do is sand your welds flush with the sheet metal and smooth them out. To do this, attach a flap sanding disk to your grinder to go over it.

Don’t gouge your metal with your grinder; you don’t want to touch any of the actual sheet metal. Rather than running back and forth over the weld (often hitting the base metal on either side of the weld and then humping over the actual weld), angle your grinder so that it only touches the weld metal.

7. Don’t freehand it, use a template

If you need to make a specific shape, or you’re trying to recreate a part, don’t try and freehand draw it.

Paper, manilla folders, cardboard, etc., make for great templates. They’re flexible, so you can fold them as needed, plus make measurement notes and mark where a piece bends or curves.

If you mess up the drawing or cutting and need to restart, you aren’t wasting metal either.

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Thanks to its ability to weld effectively at low amps, TIG welding is a great option when it comes to sheet metal.

Tungsten Selection and Prep

First things first, tungsten selection and prep. At UNIMIG, we recommend the gold-tipped Lanthanated tungstens for mild steel, but you can use any of the others that work with steel (e.g. Ceriated and Thoriated) as well.

Though tungsten type is more down to personal preference, your tungsten diameter needs to be small.

A 1.6mm tungsten is going to be your best bet on really thin sheet metal, but if you’re working on something closer to 3mm, you can use a 2.4mm tungsten. A small tungsten needs fewer amps to fully heat, and the lower the amps, the better.

Using lower amps does mean that you’ll need to move slower, as it takes more time to melt, so sometimes it might be better to switch methods. Go for a slightly bigger tungsten, up the amps and pick up the pace.

Running hot but fast means the metal melts faster, without having to linger in the one spot for as long, keeping the actual heat levels lower. If you’re not confident in being able to maintain a faster pace though, stick to a smaller tungsten, lower amps and a speed you’re comfortable with.

Regardless of the application, your tungsten needs to be prepped, and sheet metal is no different.

If you’re working with stainless or mild steel, you’ll want to grind the end to a sharp point (grinding lengthways on your grinding wheel!) to get the best results.

A pointed tip helps keep your arc and puddle as fine and controlled as possible, which is key to keeping your HAZ (heat affected zone) narrow.

If you’re working with aluminium, a balled or flattened point on the tungsten is needed.

Filler Metals

Your filler metal thickness is super important when it comes to working on sheet metal. You want your filler to be melting before or at the same time as your base metal.

If you have a filler rod that’s too thick (like using a 2.4mm rod on 1mm metal), then you’ll need more time and heat to get it to melt, which is a big no-no.

When you’re working on super thin sheet metal, you can use MIG wire as a filler rod. All you have to do is cut some off from the spool (being careful not to unravel the whole thing) and straighten it out.

Straightening the MIG wire so that it’s easier to feed through your fingers is probably the hardest thing about using it as filler for TIG.

Using MIG wire is a good option for the really thin stuff because you can get a lot smaller diameter wire than TIG rods. The smallest rod available is 1.6mm, whereas you can get 0.6mm MIG wire.

The thinner the filler you use, the easier it is to melt, and the smaller your bead will be. Just make sure if you’re welding 2mm-3mm sheet metal that you aren’t using 0.6mm wire – you still need enough metal to join the two pieces with proper penetration.

Settings

Most TIG welding on sheet metal can be done at fairly low amps. If you’re not sure where to start, check out UNIMIG’s free Ultimate Welding Guide.

It includes a full list of settings based on tungsten, filler and base metal thicknesses. Our guide is just a starting point, so if you need to fine-tune it for the best result, go ahead.

Getting yourself a foot pedal so you can increase and decrease the amp level as needed can also be really helpful.

Metal Prep

When you’re TIG welding sheet metal, you don’t want there to be any gap. You want your two pieces to be flush, and it’s a good idea to have it clamped at regular intervals while you do the tacks so that one side can’t lift or overlap onto the other.

Having a good and proper metal fit-up can save you a lot of time later. The better the fit-up, the less issues you’ll have to face when it comes to blowing out.

Keep in mind that you’re still working with TIG, so make sure your metal is spick and span, and there’s no rust, dirt, coating or otherwise on your metal when you start.

Tack Everything

Once you’re set up and ready, with your metal clamped into place, you can start your welding. TIG welding sheet metal is a lot like TIG welding any other kind of metal, with only a few changes to technique.

The first thing you want to do that’s different is your tacks.

You want a lot of tacks. Like, a lot. Making regular tacks, roughly every 5mm-10mm seems like overkill, but it’ll keep everything where it’s meant to be once you start properly welding.

If your tacks are too far apart, you’ll find that your metal sheets begin to pull away from each other and leave a gap that you’ll need to fill. Or one side could rise higher than the other, even beginning to overlap (if you’re working on a butt weld), which needs to be corrected.

As time-consuming as it may be, having close together tacks helps stop all of that from happening.

When you’re making the tacks, you want to add as little filler rod as possible. You’re almost aiming for more of a fusion weld.

That way, when you go back over the top of them for the actual joining weld, there isn’t just a big lump of metal in the way that you have to work around.

When you weld the metal together, you don’t have to skip the tacks. Instead, you weld straight over the top of them to avoid leaving a gap, so the flatter they are to start with, the better.

Once you’ve done your tacks, you can hammer and dolly all of them to remove any warpage. That way, when you start the final weld, you’ll still be working on a flat piece of metal.

After you’ve finished all your tacks and the metal’s cooled down again (which shouldn’t take long), you can go in for the final weld.

Making The Weld

TIG doesn’t put as much initial heat into the metal if it’s running at a much lower temperature, so in theory, and if you’ve got the skill level and confidence, you can run a weld without stopping across the length of an entire car panel.

If you were to do that, your weld speed and filler dabs have to be pretty much the exact same the whole way. If you’re still getting familiar with TIG or you’re just not super confident about your travel speed consistency, you can just weld small distances and jump around the panel.

But you can absolutely go for longer periods of welding than MIG. You’re not confined to only making small stitch welds for fear of blowing straight through the metal.

For example, if you’ve placed your tacks every 10mm, you could go along the span of five of them and cover a good 5cm before you stop. You don’t have to do these longer welds, and often you can feel the metal start to move or warp as you go after only a few centimetres.

Each time you feel or see the metal move, you can pause your weld, use a hammer and dolly to flatten it back out, and then restart.

Doing these shorter welds and adjusting the warpage (hammering it flat) as you go is a slower process, but it means that half your post weld work is being done during the weld instead.

You can also stagger your TIG welds instead of running along the metal in one straight line. Start your weld at one end, do your stitch weld, then jump to the other end, then come back again, alternating back and forth to join in the middle.

In general, though, TIG welding sheet metal can be done like TIG welding any other metal. Get your amps going, stick to a consistent travel speed and dab, dab, dab.

If the fit-up is tight (and thin) enough, you don’t even need filler, but you should keep it on hand to add if needed. For example, if the weld was opening up and widening, you could add a dab to cool it back down and close any gap that may have been forming.

You can, if you have a machine that is capable of it, use a pulse TIG setting on your sheet metal. Using pulse TIG helps to minimise how much heat is being put into the metal as the amps decrease and then increase (back to your set amps) at your chosen rate.

It can also help stop any blowouts that might happen, as the metal has brief moments to cool in the ‘off’ or decreased amps part of the pulse cycle.

Quick tip: The tighter you keep the arc, the fewer amps you’ll need to properly melt your filler because the heat is more concentrated. It means you can travel faster and keep your metal cooler overall. The downside to a tight arc is obviously the closer to the base metal you get, the higher the chance of dipping your tungsten into the base metal or with the filler wire.

When you stop a weld, you need to restart about 5mm back along the top of the previous weld. Wait for the puddle to form again and then continue along on the next part of the weld.

You restart like this to keep the integrity of the weld and so that there’s no little gaps or holes between any of them. Holes allow moisture to sneak in, and moisture in your metal will lead to rust down the track.

Warpage

Even though TIG can run at a much lower amp rate than MIG, you’re still going to get some warping. Warpage happens no matter what, though sheet metal is much more prone to it because you’re adding heat to thin metal. It’s just a matter of how much you can limit warping.

There are a couple of ways to help cool your metal faster. One is by blowing compressed air on it, and the other is by putting cold water over it. Neither of these will cool the metal instantly, but they will speed the process up.

Thanks to being unable to totally stop warpage, being able to go over it with a dolly and body hammer is one way to flatten your metal back out. This is possible with a TIG weld (and only on sheet metal), as it’s a softer weld, so it doesn’t crack under the hammering.

If you make your welding process as consistent as possible, when you go back in to correct the warpage, it’ll only need consistent hammering instead of light and heavy hammering to accommodate the different levels of warpage.

Blowouts

If you accidentally blow through your metal, don’t worry; you won’t have to start again. To fix a blowout, you just need to fill it back in, so start by slightly lowering your amps.

To fill the hole, begin from the outer edge and work your way in, dabbing filler as you go until you’ve reached the centre. Once you’ve filled the hole back in, you can just grind or sand it back to flush with the rest of the metal like you would with a normal weld.

TIG welding is usually used on the thinner sections of sheet metal as it’s more controlled, there’s no spatter, you can see what you’re doing better, and you can get a cleaner fit. Also, you can hammer and dolly it as you go because the weld is softer. However, it is a slower process than MIG and can be pretty time consuming if you’ve got a large panel to weld, so you’ll have to be patient.

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1. TIG gloves

There are a few types of safety gloves you can get to protect your hands, but getting some TIG specific gloves is definitely the best way to go if you’re TIG welding.

They’re thinner, so you have a better feel of the torch and the filler wire you’re feeding through your hand. They’re also still fully protective, and because a lot of TIG is done at lower amps, it doesn’t matter that they’re thinner because there’s less heat to absorb.

2. Perfect the arc

Getting your arc right is going to have the biggest impact on your TIG welds. To do that let’s first talk about distance.

In general, keeping your tungsten roughly 3mm from your joint will give you enough space to add filler while also keeping the arc concentrated and covered by the gas.

If you get too close, you’re more likely to dip your tungsten, and if you get too far away, your puddle becomes wider, and you lose the focus of your arc.

Next are your angles. Holding your torch vertical from the weld might seem like the best way to get proper gas coverage, but you lose your line of sight, and it makes it a lot harder to feed in the rod.

Instead, you want to turn your torch about 10° from vertical, in the opposite direction of travel. This gives you a bit more space to see around the torch and creates a bit more room to add filler without worrying about hitting the tungsten.

For both of these, consistency is key. Make sure you’re in a position where you can maintain your distance and angle without becoming uncomfortable or losing vision.

3. Shield your filler rod tip

While you don’t want the tip of your filler rod so close to the arc that it’s melting, keeping it in the gas is recommended.

Having the gas cover your filler rod helps keep it contaminant-free and stop it from reacting with the atmosphere while it’s waiting to be added to the weld.

4. Swap your consumables

If you’re swapping between metals, it’s not a bad idea to swap the consumables on your torch as well.

Even though TIG welding doesn’t spark or leave spatter, the consumables on your torch will still have remnants of whatever was just being welded.

These little bits could potentially contaminate your next weld, so having a dedicated set of consumables gives that extra bit of protection for your weld.

This can be especially helpful for stainless and aluminium, as they’re incredibly touchy metals when it comes to cleanliness.

5. Reduce your arc slowly

When you’re finishing a weld, don’t just let go of the pedal or leave your finish amps as high as your peak ones.

Instead, ease off slowly (and with a good post flow afterwards!) to avoid craters, pinholes and cracks in the weld. Your weld is hot, and suddenly cutting that off can shock your metal, which often results in cracking.

6. Gas lenses

Gas lenses make a world of difference to the gas coverage your weld gets. They’re generally wider, and they more evenly distribute the gas across the covered area.

They also create a more stable plume, so it’s directed straight out of the cup and onto the weld. That’s why with a gas lens and larger gas shroud you can have your tungsten stick out further without issues.

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• MIG Welding Aluminium
• TIG Welding Aluminium
• Troubleshooting

Metal Grades

There are a few types of aluminium filler wire, but the most common ones you can get are 4043 and 5356. Both of these fillers are aluminium alloys, with 4043 containing 5% silicon and 5356 containing 5% magnesium.

• 4043: use on 4000 to 6000 series aluminium
• 5356: use on 3000, 5000 & 6000 series aluminium

These different alloys give the filler wires different characteristics, the most notable being that 4043 is softer than 5356. 5356 wire is generally preferred for this reason when MIG welding, as it tends to feed better because of that little bit of extra hardness. However, if you’re welding a 4000 series aluminium, you’ll have to use 4043 filler.

Hot Shortness

Aluminium is ‘hot short’, which means that it’s prone to cracking when it’s close to its melting point. Basically, as the weld cools, aluminium is more likely to crack. It usually starts where the weld has ended and will often spread down the entire length of the weld. Cracks in your weld are bad news, and you’ll need to redo it because they’re structurally weak.

Metal Preparation

When it comes to aluminium, preparation is super important. Aluminium is not forgiving at all; anything left on it will mess up your weld.

Any dirt, paint, oil or otherwise needs to be completely removed, and that’s just the first part of cleaning it. Aluminium also has a layer of oxide on it which needs to be cleaned off.

There are a few ways that you can clean off this oxide layer. The first is with a handheld wire brush. Select a brush that you can dedicate to aluminium only because using a brush that you’ve previously used on steel or stainless can contaminate the aluminium.

You want to brush until it’s dull and lost its shine. It shouldn’t be shiny because that’s usually an indication that there’s still an outer layer on the metal.

Using a wire brush wheel or anything similar is a big no-no because aluminium is soft. It won’t clean the oxide off; it’ll just embed it into the metal further because of the high speed of the wheel heating the metal up.

If you’re using a wire brush, make sure to only scrub in one direction, as brushing back and forth can also imbed the oxide further into the aluminium.

The second way you can clean aluminium is with isopropyl alcohol or acetone. It’s a good idea to give your metal a wipe down before you hit it with a wire brush, just to ensure there’s nothing on the surface that’s going to get embedded accidentally.

Keep in mind that you don’t need to go too crazy with the cleaning because no matter how well you try to clean this off, it’s never going to be perfect.

Aluminium immediately begins to reform its oxide layer when oxygen touches it, so once you’ve wiped and/or wire brushed it, let your welder do the rest because you’re never going to get ALL of it off.

If you’re TIG welding aluminium, giving your filler rod a quick wipe down doesn’t hurt either.

It sounds like a hassle, but cleaning your aluminium thoroughly is critical because of the metal’s melting points. The arc will still ignite even if the metal is dirty or still has its oxide layer. However, if you leave too much of the oxide layer on the aluminium, you might not be able to start a weld pool.

Aluminium melts at around 660°C, but the oxide layer on top melts at about 2000°C. What that means is that you could be melting the aluminium that’s underneath the surface layer, but you won’t actually be able to start a weld pool until you burn through the oxide.

MIG Welding Aluminium

MIG welding aluminium can be a lot faster than using TIG, and you can stick to your standard DC settings, so you won’t need a machine with AC/DC capabilities.

However, welding aluminium on MIG is like ‘pushing a wet noodle through a straw’ if you’re using the standard torch. It is possible, but it can be really hard and incredibly frustrating.

Aluminium is a softer metal than steel and stainless, so trying to feed it through a torch lead becomes much more difficult because it bends easier.

There are a few ways to combat this with your MIG torch.

The first thing you’ll need to do is replace your liner with a Teflon one, as they’re designed for aluminium, which you’ll attach a neck spring to. While you’re changing the liner, switch out your guide tube to an aluminium designed one as well.

You’ll need to make sure you’ve got U-groove rollers, as these will grip the aluminium better and help stop birdnesting. Lastly, you can get aluminium specific contact tips, which will also help with the wire feeding.

The second thing to do is try and keep your torch as straight as possible when you’re welding. The shorter torch you have, the easier this is (and the shorter the travel distance for the aluminium), but it does get tricky if you have a 3 or more metre torch. Big loose curves or loops can be ok, but any tight circles are almost definitely going to kink your wire.

You’ll also need a separate gas bottle. Unlike steel and stainless MIG welding (which uses an ArCO2 mix), aluminium needs pure argon gas. If you’re not going to be welding aluminium a huge amount, then a small bottle will work fine.

You load an aluminium spool in the MIG welder the same way you would for steel and stainless, by lining up the locating lug and hole, slotting the spool into place and screwing the nut on to lock it in. Once it’s on, you can feed the start of the wire into the inlet guide, over the roller and into the beginning of the guide tube.

Sometimes this will work, but you must have the correct setup. Otherwise, you’re going to run into birdnesting.

What to do if your wire keeps birdnesting

What exactly is a birdnest anyway? What does it look it? Great questions.

A birdnest in your wire happens at the drive rollers. It occurs when the rollers are pushing the wire through the torch, but somewhere along the line it’s being stopped, so it’s not coming out the end of your torch.

The wire’s still being pushed, though, so it has to go somewhere. That somewhere is all around your drivers, where it tangles and loops over itself and looks a bit like a loose bird nest.

There are a few things you can check if your wire does birdnest, but even if you check everything, it might not work.

Change your liner

Let’s go back to our ‘wet noodle in a straw’ idea. You want your straw to be as hospitable to your noodle as you can make it. To do that, you’ve installed a new Teflon liner into your torch, which you’ve done for two reasons. One, it’s slipperier and offers less resistance against the aluminium. Two, pushing your aluminium through a liner that’s had steel in it can contaminate it.

Make sure you keep your straw as straight as possible. If you think about those crazy curly straws you got as a kid, there’s no chance a wet noodle would push through that, regardless of how slippery it is.

That’s why it’s super important your torch stays straight, and you also don’t accidentally kink it in your hands while you’re moving around. Even if you can’t see it, the liner in the torch will hold some of those small bends itself even if the torch isn’t bent.

When you change your liner, if you were inserting a steel one, you’d cut off any excess that hung out the end of the torch tip. Aluminium is different (of course). Once you’ve threaded your Teflon liner through the torch, don’t cut anything off the back, you want to keep that excess. It’s going to feed into the new guide tube you’re about to insert into the machine.

Change your guide tube

You can use some long nose pliers (or something else that will reach) to remove that steel guide tube. When the torch is unplugged, you can reach into the hole on the front of the machine to grab it.

Replace this with a guide tube made specifically for aluminium (you’ll need to cut it to size, so use the steel one you removed for the correct measurement).

You can then feed the excess Teflon liner into the new guide tube when you reconnect the torch. If your Teflon liner sticks out further than the tube and over the drive rollers, then you would cut that bit off. The liner should be flush with the guide tube.

This guide tube and liner will stop the aluminium wire from vibrating around freely in the 6cm or so between the end of the steel guide tube and the beginning of the torch liner, which is one of the biggest causes of birdnesting.

Check your consumables

Once your spool is in and the wire is threaded through the drive rollers (which you’ve swapped to U-grooves), you can hold down your torch button and feed it through.

Make sure you take your nozzle and contact tip off the torch first because you don’t want the wire to hit them and get stuck, as that would cause a birdnest in the machine.

Keep in mind that your liner, rollers, and contact tip should all match your wire’s size (e.g. 1mm wire needs 1mm sized consumables). Mismatched sizing will also cause issues because of aluminium’s softness.

That’s why aluminium specific consumables are the best to use; they’re drilled just a bit bigger to accommodate for the fact that the wire swells with the heat.

A lot of the time, you’ll be able to run the wire all the way through the lead and out the tip without issues. It’s once you put your tip and nozzle back on and try to weld with it that you start seeing problems.

Check your tensions

If your torch is straight and you fed your wire through without a contact tip, but when you tried to weld it failed, check the tension on your wire.

You can have more tension on a steel or stainless wire than you can on aluminium, and too much can flatten or deform your wire. Be careful not to loosen it too much, as not enough tension means the drivers will just spin and not push. (Getting all these things just right can be a bit of a juggling act; trial and error is the main way to find what works best for you.)

Now you’ve fixed the tension on your wire, fed the wire back through the torch, no problems there. You’re ready to weld. Your wire birdnests again. This is usually the point people start pulling their hair out at, but there’s one last thing you can check to try and fix the problem.

The tension on the spool’s lock nut. This is (again) a bit of a spin the knob until you get it right kind of deal. Too much pressure on your spool means the drivers have to work extra hard to pull the wire and make it spin.

On the other hand, not enough pressure and the wire will unravel on the spool and be impossible to feed. You can adjust this pressure by loosening or tightening the nut that holds the spool in place.

UNIMIG sells an aluminium kit that contains an aluminium liner, neck spring, drive roller, guide tube and contact tips. You can get everything you need for a standard MIG torch in one place, all in one go.

If your wire birdnests again, and you’ve exhausted all of these options, it might be time to try out a spool gun instead. Life will be much, much easier if you purchase a spool gun.

Spool gun

Spool guns were designed specifically for welding aluminium. Instead of feeding your wire through a long torch lead, the spool holder is attached to the gun, reducing your travel distance from 4-metres to roughly 30cm. It also includes a small wire drive inside, which feeds the wire through. There’s no fiddling around with the correct liner or straightening your torch; you can lock your spool in and be ready to go in just a few minutes.

Setting up your spool gun is relatively simple, and most of the process is pretty similar to setting up your standard MIG torch.

Keep in mind that when you detach your MIG torch, if you have a steel or stainless spool already loaded inside, you’ll need to cut it behind the inlet guide and hook it in the roll or tape it down. You’ll then need to pull all the wire still in the torch out.

Once you’ve removed your MIG torch, you can attach your spool gun. UNIMIG spool guns have a Euro connection, so they plug into your machine just like your MIG torch does.

The next step is to attach your wire spool. This, again, is done pretty much the same way as with a normal torch:

• Unscrew the nut and lift the plastic casing off
• Release the spool brake
• Slide your spool onto the shaft
• Feed the first part of the wire through the inlet guide (found at the bottom) and between the drive rollers
• Reapply the spool brake
• Put the plastic casing back on and re-screw the nut

Spool guns are pre-loaded with U-groove rollers, but just remember that if you change your filler wire thickness, you might need to change those rollers to match.

There is one additional step for a spool gun, and that’s making sure to flick the switch on the machine to ‘spool gun’. Now you can hold the trigger and feed the wire through.

You’ll still need to take off your nozzle and contact tip so the wire doesn’t catch, but at least you don’t have to wait for it to fill 4 metres of torch.

Even though the setup is the same, welding aluminium with a spool gun requires a bit of a different technique to get it right. You’ll need to increase your travel speed.

With increased travel speed comes increased wire feeding speed, which means turning your voltage up. Your wire feed and voltage still need to work together.

Because you’re adding more wire into the weld, to get a proper weld and not just have little blobs on the surface, you’ll need to move across the joint faster than you would with steel. Aluminium is also incredibly heat absorbent, which is another reason you’ll need to up your pace.

UNIMIG machines come with a setup guide inside the door, which includes recommended settings for aluminium. It’s not a bad idea to start with lower volts than what is recommended (if it recommended 13V, then try 11V) so you can make sure they’re right, but also so you can get an eye for what too low does look like.

If your voltage is too low, the wire will make little round balls or globs (because it’s not melting properly) at the tip and fall into the weld, rather than looking like it’s flowing steadily.

Tips for your aluminium MIG weld

1. Use the right technique

One of the most important things for getting a good aluminium weld is your angle. Aluminium should always be pushed. (Anything with gas should be pushed.)

If you pull (or drag) your aluminium weld, you can trap the contaminants inside the weld puddle, resulting in a poor-quality weld. Plus, you won’t get any penetration if you pull it.

However, if you push, the argon gas can properly shield the molten weld pool and keep it clean.

2. Thoroughly clean your metal

MIG welding aluminium is naturally a dirtier process than TIG welding it and a thin layer of black soot on the weld is normal, as well as a bit of spatter, but too much soot is a problem.

Cleaning your aluminium thoroughly and making sure it is spick and span is just as crucial on MIG as it is for TIG.

3. Get the gas flow right

One of the things that will affect how black the weld is is the travel angle and the gas. In general, a higher gas flow is recommended for aluminium in comparison to steel. If you’re getting a lot of black soot, try turning your gas up first, with your gun at roughly a 5° to 10° pushing angle.

Don’t go too crazy with the gas though, you’re not going to be able to get rid of all the soot no matter how high it is, and too much gas will give you an erratic arc. Plus, it’s wasteful.

If your gas flow is quite high and you’re pushing but still getting soot, check that the gas itself isn’t contaminated (yes, that can happen) or that there aren’t any places in the torch that oxygen is getting in.

4. Fill in the ends

When you finish an aluminium weld, you’re often left with a crater or ‘fisheye’ at the end. This looks like a round dent, and it can cause a few issues if it isn’t filled in.

To fill it in, when you reach the end of your weld, pull your torch back into the puddle and let it bubble before you release the trigger.

The other way to fill it is by dashing it a few times. When you reach the end of your weld, release the trigger for a half-second, and then press it quickly, as if you were adding tacks, onto the end of the joint to fill it.

If you leave your crater unfilled, you may find that your weld cracks after some time. This is especially true for any welding done to trailers or anything that’s subject to constant vibration.

The crater is the weakest part of the weld, so when put under too much pressure, or constant vibration, it can crack. The crack can spread all the way down your weld, even if the rest of it was structurally sound.

When you end a weld, whether you’re making tacks or running a joint, your aluminium wire will usually form a small ball. You’ll need to cut this off before you start your next weld.

MIG welding aluminium can be tricky, and it’s not nearly as good looking as a TIG weld, but it’s a lot faster, so it’s usually more preferred for a lot of production work. It does depend on your material thickness as well. 2mm thick base metal is about as thin as you can get with MIG; any thinner and you’ll need to TIG it.

TIG Welding Aluminium

TIG welding aluminium is arguably harder, but there are more options to play with that will affect (and probably improve) the weld than there are with MIG. It’s definitely a slower process feeding the wire in by hand yourself, but you can get finer, nicer looking welds with it.

As with all TIG welding, the first thing you need to do is choose and prepare your tungsten.

So, which tungsten should you choose? You can technically use any tungsten that can run on AC (Lanthanated, Zirconiated, Ceriated and rare earth). Depending on who you ask, you’ll get a different answer, but we recommend Zirconiated for its arc stability and AC performance.

Now that you’ve picked a tungsten, you’ll need to prepare it for the weld. The rule used to be that if you were welding aluminium, you’d need to ball the tip of your tungsten (mostly because operators used to mainly use a pure tungsten).

Every machine used to be a transformer machine, and these, paired with pure tungsten, would mean that to prepare the tungsten, you held it over a piece of copper (in AC) at a high amperage until the tip had formed a ball.

These days, with improved technology, TIG machines are now almost always inverter machines, which means that you can prep your tungsten how you would for a steel weld, by grinding it to a point.

A pointed tip will give the arc more focus, but when in AC will still cause your tungsten to ball naturally. The ball in these instances will be nowhere near as big as what would’ve appeared on a pure tungsten and generally doesn’t affect the weld very much.

You can influence how much your tungsten tip balls by changing your amps and AC balance settings.

Unlike MIG, welding aluminium with TIG is always done in AC. There’s one main reason for this, and that’s because the AC cleans off the oxide layer as it welds. But how does it do it?

AC Balance

AC stands for Alternating Current. When you’re using DC, you can choose if you’re using a negative or positive current. In AC, you get both. It flows between negative and positive in a ‘cycle’.

You can, however, choose how much time will be spent in positive and how much time will be spent in negative. This is your AC balance.

The positive and negative currents have their own properties, which is why some welds may require different percentages of positive to negative.

The positive part of an AC cycle is what cleans the metal, and the negative part is what provides the heat and penetration for the weld.

In general, if you’ve pre-cleaned your metal, a 30% positive to 70% negative ratio will work pretty well. The setting varies between machines, but it should either say ‘balance’, ‘%’ or have an image of a square wave on it, which will indicate that you can adjust the balance.

Increasing your positive percentage will increase the cleaning on your workpiece. However, the more you up your cleaning, the less penetration you’re going to have. You pretty much never want a 50/50 balance, as you won’t have enough heat to actually make a weld pool.

Besides your lack of penetration, upping your cleaning means you spend longer in the positive part of your AC cycle. The longer you spend in the positive, the hotter your tungsten gets.

This heat, however, does not get transferred into the metal. Instead, it sits inside the tungsten, which results in your tungsten balling and then melting entirely. If your tungsten starts melting, there’s a good chance part of it is going to end up in your weld pool, which will contaminate it.

At UNIMIG, every one of our dedicated TIG welders comes with the ability to adjust the AC balance (except the RAZOR TIG 220 DC Welder, as that can’t run AC).

When using any of our machines set to AC or AC pulse, you can scroll through using the knob to the ‘AC Balance’ setting, which has a picture of a square wave.

UNIMIG TIG welders are partly synergic, in that once you’ve programmed in the tungsten electrode size and your amps, it will automatically select what it believes to be the best balance setting for your weld. However, if you find that you’re not getting enough cleaning or penetration, you can manually adjust it.

When you scroll through to the setting, the machine will read 0, which is what the machine has selected. You can change this up to +5 and down to ­­-5, with negative numbers meaning less cleaning (and more penetration) and positive numbers meaning more cleaning (and less penetration).

AC Frequency

The AC balance is not the only setting that affects your weld. The frequency of your cycle also plays a role in how your weld is going to turn out. While your balance determines how long you spend in the positive and negative currents per cycle, your frequency will determine how many cycles are completed per second.

Older machines won’t let you change this at all and are generally set to a standard 60Hz per second. However, with newer technology, you now have the option to increase or decrease your frequency as well.

Turning your frequency up and down will change your weld profile and the sound that the machine makes. UNIMIG TIG machines have a frequency range of 20-200, and this can be adjusted by scrolling through to the ‘AC Hertz’ setting.

The higher the frequency, the more cycles per second, which creates a thinner, more prominent weld appearance as the arc becomes smaller and more focused. The lower your frequency, the flatter your weld will be.

A higher frequency is usually recommended for thinner metals, as the arc is tighter, so you can be more accurate in thin joints (like outside corners).

The higher your frequency, the higher the pitch of your weld, so if you’re welding with 200Hz all day, investing in earplugs will be a lifesaver.

Tips for your aluminium TIG weld

The actual process of TIG welding aluminium is basically the exact same as TIG welding steel or stainless. Start your arc, form a weld pool and feed in your filler rod. There are, however, some things that are different.

1. Get a foot pedal

Being able to control your amps is really helpful for making a good aluminium weld. While you can program in start amps, up slope, peak amps, down slope and finish amps, using a foot pedal is probably the easiest way to weld aluminium.

You may need to fluctuate your amps in the middle of the weld, which isn’t really possible with just a torch. Aluminium heats up fast, so easing off from your peak amps halfway through the weld can help with distortion and melting through to the other side.

The foot pedal means you can ease up slower at the end of your weld and cool the metal down gradually. This, plus your post flow, is critical to stopping your weld from cracking because of aluminium’s ‘hot shortness’. A pedal also lets you start cooler and clean the start of your weld for longer.

2. Make sure the cleaning is happening

You can see the cleaning happening when you begin a weld, as the top oxide layer almost looks like snow melting off the ground as the metal heats up.

This cleaning continues all the way along your weld, so you’ll find when you’re done that there’ll be an outer edge of white around your weld bead. This frosty look is the oxide layer that’s been cleaned from your weld by the AC.

It’s a good sign and gets wider or narrower depending on your AC balance. It can be cleaned off at the end of your weld with a wire brush with no issues.

3. Let the puddle form

You will need to wait until the weld puddle has fully formed and you have a shiny pool before you begin adding your filler metal. Because of the cleaning action that happens at the start, it may take some time. Give your weld a few seconds to form a proper puddle before you start dabbing in filler.

4. Watch the heat

Like MIG welding, you’ll generally need to move along the joint faster than you would with steel. If your metal is getting too hot and you have a foot pedal, then you can back off your amps a bit to help bring the heat back down.

Otherwise, you can add more filler, or dab more frequently, to keep cool the weld. The colder filler rod helps to bring the overall temperature down.

5. Finish strong, not harsh

Once you reach the end of your weld, as well as easing off your amps slowly to prevent cracking, you can also add some extra filler metal to fill in the crater that would otherwise form. If you’re using a torch, setting your finish amps lower than your peak is recommended; you don’t need to keep your amps full blast on the edge of your metal.

Troubleshooting Your Aluminium Welds

Is your metal clean?

One of the main things that will affect your weld is how clean your workpiece is. This is probably the most crucial step, and most issues can be resolved by giving it a more thorough clean.

Things like excessive black soot (when MIG welding), porosity, black floaties, peppering in the weld and ‘skin’ (think of the layer that forms on tomato soup that’s been left out) can usually all be fixed by going back to step one and giving the metal a good clean.

Check your gas

If you’re getting a thick ring of black soot around your bead when MIG welding and your aluminium is as clean as you can get it, then it’s most likely a gas problem.

The first thing to check is whether or not you’re using the right gas. You should be using pure argon. Try turning the flow rate on your gas bottle up and see if that helps, as you might not be getting enough coverage.

If that doesn’t help, your gas might be contaminated, or there could be a leak. If it’s contaminated gas, then you’ll need a whole new cylinder. If your gas hose is leaky, then you’ll need to replace it.

It’s pretty unlikely you’ll completely eliminate the soot, but a thin ring typically means that the gas is cleaning contaminants and blowing them out of the way of your weld, so the actual joint will be fine.

Maintain your contact tips

While we’re on common problems you get when MIG welding, let’s talk about contact tips. Whether you’re using a standard torch or a spool gun, you should expect to go through a few contact tips.

Because aluminium absorbs heat faster and you need to move along the weld faster, you need to increase your wire speed to match. The problem is if you don’t have enough wire speed or your volts are too high, the filler wire burns back.

It’s called burnback, and this is how far the wire recedes when you stop welding. If your wire does burn back onto the contact tip, it can ruin it, and you’ll need to replace it to keep welding.

Fill the ends

Whether you’re MIG or TIG welding, fisheyes in the crater at the end of the weld are not good. In both cases, you want to add more filler wire to fill in the crater. You should also leave your torch over the weld so that it remains shielded by your gas until it has fully cooled to prevent cracking afterwards.

How thick is the parent metal?

Your parent metal’s thickness is also going to play a role in how well your weld comes out.

If it’s too thick and you’re MIG welding, there’s a good chance your filler wire is now sitting on top of the joint rather than inside it.

If you’re TIG welding, you might not be able to even start a weld pool because the torch can’t get enough heat into the metal.

Make sure you’ve got a machine that’s got enough amps for your material’s thickness. You can also try preheating (more on this later), but that’s not always guaranteed to work.

Another trick you can try is using an argon/helium mixed gas. Pure argon is generally recommended, but adding helium to your gas will give you more heat if you need just that bit more penetration. It’s like turning your 200 amp machine into a 250 amp machine.

Tungsten choice

There are a number of things that can go wrong with a weld that are TIG specific. 

Using the wrong tungsten size is relatively common, as you generally need to go up in tungsten size for aluminium compared to steel.

For example, say you’ve got a machine that goes up to 120 amps max, and you’re welding steel on DC. You can put a 1.6mm tungsten in your torch and crank the amps all the way up to 120, and that’s fine; your tungsten can handle it with no problems (120A is usually about the max for a 1.6mm tungsten, though).

However, if you were to use that same tungsten at 120 amps on AC, it’s a totally different story. Because the current flows in two directions, rather than just one, it makes it much harder for the tungsten to cope.

Your tungsten will start balling, melting, splitting and otherwise. It will break down. Technically, you can still weld with it in this condition, but your arc will be super erratic, and there’s a good chance the tip of your tungsten ends up in the weld pool, contaminating it.

There is a super easy fix to this problem, though, and that’s upgrading to the next size tungsten. If 1.6mm can’t handle it, grab a 2.4mm instead.

Don’t use a 50/50 balance

The next thing that can go wrong is your settings, specifically your AC balance. A 50/50 cleaning to penetration does sound like it would be the optimal settings. The best of both worlds, right? Wrong.

Too much time on the cleaning part of the AC cycle can seriously harm your weld, and in most cases, actually makes it dirtier. The contaminants it’s trying to remove often get stuck on the surface of the weld, and you end up with the peppered effect.

Too much of the positive current in AC also makes your tungsten ball really quickly, so you might find your arc starts to wander halfway along the joint. That’s because your nice sharp point (which you started with on an inverter machine) has now turned into a fat circle that’s not concentrating your arc. Turn the cleaning down, add some more penetration, and you’ll be good to go.

Tungsten contamination

Like regular TIG welding, tungsten contamination is another thing that could be affecting your weld.

When you get filler metal on your tungsten while welding steel, it can be pretty obvious; the arc starts sputtering and becomes unstable. The same goes for aluminium.

Once the aluminium is on there, the arc starts wandering. Some of the common symptoms of tungsten contamination are globulars (your filler sits on top of the metal, rather than fuses with it), black soot, a wandering arc or your puddle doesn’t flow.

Unfortunately, if your tungsten does get contaminated, you can’t just grind it off because aluminium camouflages very well on tungstens, and even if it looks clean, it might not be.

Instead, you’ll need to break the end off. To do this, you can snap it off against a sharp edge, or you can use a grinder to cut it. You’ll need to break it in one quick motion, as tungsten has the tendency to splinter if you break it slowly.

Once the contaminated tip has been removed, you can regrind it into shape and start again.

Storage

Aluminium has to be stored correctly, as it can become contaminated if not, which will affect your weld quality.

Placing it in a dry, clean space is your best option, preferably at a consistent room temperature. If aluminium is stored somewhere cold and then is moved into room temperature or a warmer area, it can cause condensation on the metal. Moisture on your filler metal, whether it’s 4043, 5356, a MIG spool or a TIG rod, is going to give you a bad weld.

Placing the filler back in its original packaging will help protect it against dirt and other bits, and only handling it with gloves will keep the natural oils from contaminating it as well.

Preheat

Preheating for thicker pieces is a good idea, especially if your voltage or amperage is already pretty high. Just take a propane torch and put some heat into the metal as evenly as you can.

You don’t want it to be melting, but it helps with penetration if your metal already has some heat in it, rather than going from a cold start. If you do preheat your metal, doing a quick test run is recommended, as you’ll need to be moving faster if your metal is already hot.

Welding aluminium takes a bit more juggling compared to stainless and mild steel. Practice runs on scrap metal are going to be your best friend while you learn. Even if it takes you a few tries, don’t worry, it’s a hard metal to work with.

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The key to MIG welding sheet metal is to run it on the same settings as though you were doing a vertical up weld. However, don’t forget that if your machine is running too cold to properly melt your filler and penetrate the metal, you’re going to have to spend extra time in each spot, which adds more heat. The trick to sheet metal is finding the right balance.

Filler

You can do a couple of things to combat this extra heat, the first of which is picking the right wire size. In general, don’t use a wire that is thicker than your sheet metal.

If you’re welding 1mm thick steel sheet metal, then you’ll want to use an 0.6mm wire for the best results, although 0.8mm would also work. The thinner your wire, the less heat you’ll need to melt it, and so the less heat you’ll put into the sheet as you work.

For the same reason (keeping your heat level down), you don’t want to use flux-cored MIG wire, as it requires more heat and more post-weld work.

Gap or No Gap?

There are two ways that you can fit up your metal: with a gap or without one. There are pros and cons to both ways, but if your metal is thinner than 3mm, you won’t need a gap.

Gap

When fitting your sheet metal together, you can leave a small (like 1mm small) gap between the two pieces.

When you go to weld, you’ll fill this gap with the filler wire, which allows for better penetration as there’s space for the wire to fill (which can help as MIG often deposits more metal).

The problem with leaving a gap, especially if you’re still learning, is that it can be difficult to properly fill. Plus, if you get your machine settings wrong and do blow through the metal, then you’ve got an even bigger hole to fill back in.

If you work with a gap between your metal, a good technique you can try is to start with your torch at a steep angle (around 45°, nozzle resting on the plate). Angling the torch means you can see what you’re doing.

As soon as it’s puddled, pull the torch up, back to 90° (vertical). The entire movement should occur over the span of 1-2 seconds, so you don’t blow through.

You’re still making a tack weld, but doing it this way basically ‘leads’ the puddle from one edge to the other, giving you full penetration. It also leaves a relatively flat bead, so you’ll have less grinding to do later on.

No Gap

If you don’t leave a gap and press the two pieces directly together, then you’ll need to run a bit hotter than if you were leaving a gap. The reason is, with no gap, you’re trying to melt the two pieces directly together, so you need them both to have melted. No gap does mean you can achieve flatter welds if you have your machine set to the exact settings.

Settings

When you’re working with sheet metal, the best thing you can do is get some extra metal that’s the same thickness and play around with the settings (and practice your speed). That way, you’re not trying to figure it out on the main piece, and you can tweak them as needed.

If you’re working on a car panel, finding out you’re running too hot and blowing a hole through the actual piece is not how you want to learn.

Grab some spare metal, and make sure that your machine is running hot enough to form a puddle and penetrate properly before you start on the real thing.

If your weld bead is crowned and you’re not getting full penetration, you can turn the volts up and/or wire speed down. You want the weld as flat as possible, so minimal grinding is needed at the end.

Making the Weld

Once you’ve got your machine all set up, it’s time to weld. The two most common techniques are a spot/tack weld and a stitch weld.

To do a spot weld, hold your torch over the joint, press the trigger for 1-2 seconds until you can see a puddle form. As soon as you see this puddle, you can release the trigger. That’s your spot (or tack) weld done. It’s exactly like if you were making a tack on a normal weld joint to hold the two pieces together.

To weld a full sheet, you make a series of spot welds, with each new spot overlapping the previous weld by about half. Welding with the overlap ensures you don’t leave any gaps.

When making a series of tack/spot welds, you only want to do about 3 or 4 overlapping tacks in one spot, as any more and you risk burning through the now heated plate. Then move to the other end of your weld and make another series of overlapping spot welds.

A stitch weld is a continuous weld that is short, only 2cm-3cm long. Rather than having a series of overlapping tacks, you’d instead have a small run. If you’re going to be stitch welding, make extra sure that your settings are spot on.

Like with tack welding, you don’t want to make your stitch welds directly next to each other. Start at one end and swap to the other so the metal doesn’t overheat in one spot.

The idea is to move around the plate as you go, to evenly distribute the heat and stop it from warping. Don’t go back to a previously welded area until it’s cooled down. You’ll know it’s ready to be welded on again if you can touch it with your bare hand.

Welding sheet metal can take a lot of time (and patience), especially if you’ve got a long panel to weld, but if you rush through it and try to run a long bead on it, you’re just going to end up with problems that’ll need fixing which will take even longer, so take your time.

Quick tip: keep an eye on your MIG wire stickout each time you pull away, as you want to trim it whenever a ball forms on the end. The ball that forms is thicker than the wire, which means you’ll need more heat to melt it in. If it doesn’t cause you to blow through your sheet, you’ll have to grind the excess metal off later anyway, so it’s best to just trim it.

A good way to keep from accidentally blowing through is to insert a copper backing plate behind the joint (one that you can remove!). The copper helps to absorb the heat being pumped into the metal, and because it’s a dissimilar metal, the weld won’t stick, so you can pull it out when you’re done.

Post Weld

When you’re working with sheet metal, especially if it’s for car panels, there’s usually going to be some post weld work, especially when you’re MIG welding. You need to make the weld flush with the base metal so that when you paint it, there aren’t any obvious areas that stick out.

Because you’ll be grinding the top part of the weld off, it’s super important that you get complete penetration. If your weld hasn’t gone all the way through to the back, when you grind down and smooth out the top of your weld, you’re losing most of it.

The other thing to keep in mind, and why you’re trying really hard to make your weld sit flat in the first place, is that you have to grind it flush once you’re done. The flatter your final weld, the less grinding you’ll have to do after.

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Quick Navigation

Jump to:

• Porosity
• Cracks
• Undercut
• Overlap
• Distortion
• Burn Through
• Lack of Fusion
• Lack of Penetration
• Slag Inclusions
• Spatter
• Craters
• Convex and Concave Weld Beads

1. Porosity

What is it and what does it look like?

Porosity occurs when elements in the atmosphere are absorbed into the weld pool while it’s still molten. These gases become trapped once the metal solidifies, and you’re left with a weld full of holes. Porosity is often referred to as the ‘swiss cheese’ look because of the little bubbles left behind.

What causes it?

• Dirty parent metal
• Not enough shielding gas
• The wrong type of shielding gas
• Contaminated gas
• Incorrect torch angle or position

How can you prevent or fix it?

• Thoroughly clean your parent metal and give your filler a wipe down
• Clean your consumables and replace any that are worn or damaged
• Make sure all of your equipment is moisture free
• Check your gas flow (UNIMIG recommends 8-12L/min), make sure it’s not leaking or empty
• Check you have the correct type of gas: ArCO2 for MIG stainless and steel, pure argon for MIG aluminium and all TIG
• Angle your torch 45° and roughly 3mm off the joint for good positioning
• If there’s a draft or you’re outside, set up some makeshift walls to block any wind

2. Cracks

What is it and what does it look like?

There are 3 types of crack that you can get:

Hot Cracks

Occurs when the strain on the weld pool is too high, or it is forced to cool too fast.

Cold Cracks

Unmalleable material, residual stress (from constant vibration or flexing) and diffusible hydrogen inside the metal can all create cold cracks.

Crater Crack

Occurs when the end of a weld isn’t filled properly, a weak point forms and can crack.

Sometimes, a crack won’t immediately form, and it’s not until days, months, or years later that the metal begins to crack. Once it’s there, though, it’ll only get bigger. The problem with cracking in a weld is that you can’t just go back over the top of it and fill it in. You have to remove that part of the weld, or the entire weld, and restart from scratch. If you can prevent the crack from forming in the first place, then it’s going to save you a lot of time and effort.

What causes it?

• The wrong type of shielding gas
• ‘Shocking’ the metal (not cooling it slowly enough under shielding gas)
• Using the wrong type of filler metal
• Not filling the joint in properly, especially at the end (this will cause a crater crack)
• Poor joint configuration and preparation

How can you prevent or fix it?

• Use the correct type of gas for your metal type
• Cool your metal slowly, using an appropriate amount of post flow for your weld (TIG)
• Pre-heating and post-heating your metal so that the temperature range isn’t so severe
• Make sure your filler metal’s tensile strength and metal grade matches or is as close as possible to your parent metal
• Use a ‘backfill’ method to add extra filler at the end of your weld and let the weld build up slightly to prevent craters
• Clean, grind, deburr, bevel and clamp your joint so that it’s lined up as tight as possible with no impurities
• If a crack has formed on your weld, you’ll have to grind the whole thing off and start again

3. Undercut

What is it and what does it look like?

Undercut occurs when the weld gets too wide, and the base metal dips in along the edges (due to poor welding technique), but there is not enough filler material to fill the gap, so you are left with a groove on the toes of the weld.

What causes it?

• Arc length is too long
• Too many amps or too much heat
• Not adding enough filler
• Too fast a travel speed
• Angling the torch too far in one direction

How can you prevent or fix it?

• Make sure to keep a tight arc
• Lower your amps and heat so that you’re not excessively digging into the joint
• Slow your travel speed, so there is enough time to fill in the joint properly
• Keep your torch tip centred on the middle of the joint or towards the thicker metal
• If the pass is wide, or you’ve gotten undercut, use multiple passes to fill it in

4. Overlap

What is it and what does it look like?

Overlap is pretty much the opposite of undercut. There is too much filler in the weld, and the machine is running too cold (not enough amps). The type of joint you’re working on will determine whether you’ve got overlap or not. There’s usually a bit of wriggle room with a butt weld, as the bead is generally slightly convex on these. A fillet weld, on the other hand, should be mitre (flat in the joint). Either way, the bead should be fused into the edges rather than hanging over them.

What causes it?

• Too much filler metal
• Incorrect welding technique
• Not enough heat (amps/volts)

How can you prevent or fix it?

• Use less or a smaller filler wire
• Make sure you’re welding at the correct angle with a good arc distance
• Increase your volts (MIG) or your amps (TIG & stick)

5. Distortion

What is it and what does it look like?

Distortion can also be referred to as warping, in which the metal hasn’t been able to cope with the expansion and contraction that comes with heating and cooling. It often looks as though the metal has begun to pull and warp. A lot of the time, it means there’s been too much heat in the plate, not just the joint, which the metal can’t handle.

What causes it?

• Too much heat
• Travelling too slowly
• Not clamping enough
• Not enough tacks

How can you prevent or fix it?

• Where possible, do short welds or stagger your welds to spread the heat
• Increase your travel speed (but up your amps, so the puddle still forms) so less heat sinks into the parent metal
• Weld on both sides, the metal will often pull towards the weld, welding the opposite side pulls it back
• Let your weld cool in between passes
• Clamp your piece correctly; use turnbuckles and lots of clamps if need be
• Use lots of tacks
• Metal is always going to warp, even if it’s just slightly, once there’s heat in it; the important thing is to minimise the amount of distortion, especially on critical welds
• If you do end up with warped metal, you can go back and re-heat it to fix it; there are plenty of ways to reshape it (e.g. hammer and dolly)

6. Burn Through

What is it and what does it look like?

Burn through is, literally, burning through your metal so that filler protrudes out the other side, or in more extreme cases, where you’re left with a hole.

What causes it?

• Too much heat in one concentrated area
• Too high an amperage
• Too slow a travel speed

How can you prevent or fix it?

• Turn your amps down
• Increase your travel speed
• If you’ve put a hole in your metal, there are two things you can do
  • you’re going to need to start again from scratch and grab some new metal, or
  • you can adjust your settings, fill the hole in, grind it down and then weld over it as if it was never there

7. Lack of Fusion

What is it and what does it look like?

A lack of fusion occurs when the weld metal doesn’t fuse with the base metal properly. You can also have a lack of fusion between multi-pass weld beads. There are often gaps along the edge of the weld, and it’s usually characterised by a high crown weld bead. You might not be able to see how well it’s fused on the actual weld, but if you can break it apart by placing it in a vice and cracking it apart, then it wasn’t fused together properly. You can also check the fusion with an x-ray or other non-destruction methods.

What causes it?

• Too fast a travel speed
• Not enough heat
• The torch angle is incorrect
• The filler metal or electrode size is not big enough
• Incorrect joint design or fit-up

How can you prevent or fix it?

• Increase your amps and slow your travel speed
• Wait until a wet pool has formed on the metal before moving and focusing on pushing or pulling it along; you want to be in control of it
• Make sure that your joint is lined up properly, with the correct sized gap

8. Lack of Penetration

What is it and what does it look like?

A lack of penetration means that your weld bead hasn’t gone all the way into the joint. The groove or root of the metal hasn’t been completely fused. This is a lot easier to see on a butt weld (that’s not attached to anything), as you can flip it over and check the backside to make sure the weld bead has fused to both sides and filled in the entire space. Like a lack of fusion, if you’ve got shallow penetration, the weld can be deemed faulty for crucial situations.

What causes it?

• Too small a root gap or a misaligned/improper joint fit-up
• Not enough heat
• Too fast a travel speed
• Using an electrode that is too large with amps to match (TIG)
• Poor welding technique

How can you prevent or fix it?

• Check that you’re using appropriate amps/volts/wire speed and travelling at a speed to match
• Make sure that you’re holding your torch at an appropriate angle with a tight arc
• Prep your root gap so that it is not too narrow you can’t get into it, but not so wide you can’t fill it and that everything is lined up

9. Slag Inclusions

What is it and what does it look like?

A slag inclusion occurs when a piece of flux falls off and ends up in the weld pool but doesn’t melt out, becoming trapped inside and contaminating the weld as it solidifies. These only happen when stick and gasless MIG welding, as they’re the only two that use a filler metal with a flux core or coating that can come off. A slag inclusion will typically leave a hole in the weld with the slag exposed.

What causes it?

• Slag wasn’t removed prior to the next pass (on multi-pass welds)
• Poor quality or poorly stored electrodes
• Using the wrong welding technique (pushing instead of pulling)

How can you prevent or fix it?

• Store your filler metals in a cool, dry space, preferably sealed in a container
• Re-bake any damp electrodes before use
• Use the proper welding technique: pull (drag) the filler
• Maintain a good arc length
• Clean slag off properly between welds

10. Spatter

What is it and what does it look like?

Spatter is the small balls of metal that surround a weld once you’re done. While welding, the sparks that spray from the torch or electrode often include little bits of molten metal, and these are left around the weld once they’ve hardened. They don’t actually cause any harm to the weld, but it certainly adds to your clean up time after you’re done with the weld. Stick and MIG welding are the main welding processes that will produce spatter, and a lot of the time, it’s impossible to not create it. There are a few ways that you can minimise how much spatter you do make.

What causes it?

• The amps are too high
• The volts are too low, or the wire speed is too high (MIG)
• The arc length is too long
• Your work angle (torch position in relation to joint) is too steep

How can you prevent or fix it?

• Move your torch or electrode closer to the joint to shorten the arc length (a good length is 3mm)
• Readjust your amps/volts
• Prep your metal and clean any dirt, paint, or otherwise from the surface
• Use an anti-spatter spray so you can just chip it off once you’re done, rather than coming back with a grinder

11. Craters

What is it and what does it look like?

A weld crater is a dip or hole at the end of a weld that hasn’t been fully filled. Weld craters can happen on any kind of weld. They can often lead to cracking, so filling the end of your welds is important.

What causes it?

• Not enough filler metal deposited at the end of the weld

How can you prevent or fix it?

• Pause for a few extra moments (or dab extra filler for TIG), and let the weld bead build up slightly
• Ease off the amps slowly to narrow the weld pool as you come out of the weld
• Once you reach the end of the weld, ‘back step’ to fill in the end

12. Convex and Concave Weld Beads

What is it and what does it look like?

A convex or concave weld bead is generally a sign that something is not quite right with your weld. If the correct settings and technique have been used, the weld should lay flat (mitre) against the parent metal.

What causes it?

• A convex (or ropey) bead is caused by
  • Not having enough heat to properly flatten the weld at the same time as,
  • Travelling too fast
• A concave bead is caused by
  • Too much heat
  • Travelling too slow

How can you prevent or fix it?

• Adjust your settings and travel speed to suit your parent metal (UNIMIG machines all come with a settings guide)
• Make sure you’re using the proper welding technique: push for gas and pull for gasless

Almost every issue you encounter when welding can be prevented with proper preparation. It can seem like a lot of work and hassle, but doing it in the first place will be a lot faster than having to remove a dodgy weld and start again (and then still need to be prepped!).

If you start with dirty metal and a poorly calibrated machine, you’re not going to get the greatest weld. Be patient, and if something goes wrong, we can help identify and solve the problem so you can be back up and running in no time.

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Here are a couple of tips for prepping yourself before a weld so that you’re as comfy as can (practically) be.

1. Rest your hands

Having steady hands can make or break a weld. If you’re working on a bench or otherwise flat surface, support your wrists, forearms or elbows against it.

Being able to lean up against a solid surface will give you more control as you run along a joint; there’ll be less movement in your torch, giving you a more consistent weld. You can set up a wood or metal block to elevate your hands for the same effect if you need to.

If you’re welding vertical or overhead, you can attach a clamp to something nearby, and then use it to lean on instead.

2. Get rid of some weight

If you’re welding out of position, overhead, vertical, you name it, you’re going to be dragging the torch lead along behind you as you go. These can get pretty heavy, especially if you’re holding the torch above your head. That extra weight can build pretty quickly.

Grab a chair, bench, horse or otherwise and drape your torch lead over it. You can eliminate a lot of that extra weight by having something else support the length of the torch so your arms and shoulders don’t get tired so fast.

 3. Use both hands

Welding with both hands is always going to be better. Holding the torch in one hand and using the other for support and guidance will help your weld and keep you stable. Tack your job so that you can have both hands available, and then use both of them to keep your arc and torch steady and consistent.

This doesn’t apply to TIG, as one hand is needed to feed in your filler metal, but it definitely applies to stick and MIG welding.

4. Put something under your knees

If you have to weld on the floor, get something for your knees. If you can move whatever you’re welding off the floor, that’s even better, but kneeling down trying to weld can get painful.

Get an old jacket (the thicker, the better) or knee pads, anything that’s softer than the ground to protect your knees.

5. Make sure you can see

If you can’t see what’s going on, you’re not going to get a nice weld. Make sure that you’ve got a good, clear view of your arc and weld. The best way you can do that is with a good helmet.

The bigger your viewing lens, the more you’ll be able to see out of it. On top of that, keep your helmet clean. If the lens is dirty or scratched, you’re not going to be able to see regardless of how big it is.

For TIG welding, you can get quartz cups. They’re see-through, so you can see what you’re doing better. No more straining your neck trying to get a good view of your weld.

6. Flex head torches

Some MIG and most TIG torches come with the option of getting a flexible neck these days. Instead of bending or folding your body and arms in weird ways to reach tight spots, you can just bend the torch neck.

If you’re stick welding, you can bend the electrode where it inserts into the holder if you’re trying to weld at an awkward angle.

7. Tidy your leads

Before you start a weld, just take a moment to make sure that your torch lead, power cables, or anything else that you’ve got plugged in is neat. You don’t want to find halfway through a weld that your torch lead has wrapped itself around your chair or something else, and now it’s tangled and stuck. Keep it tidy.

8. Sit down

If you’re TIG welding, sit down. It sounds super lazy, but seriously, if you can reach the weld sitting, do it. If you don’t have to hunch over and give yourself back problems, that’s a bonus, and it’s going to show in your weld. Sometimes sitting isn’t possible, like if you’re doing an overhead weld, you won’t be able to sit for that, but if you’re working on something at a bench, go ahead and take a seat.

Unfortunately, this doesn’t apply to MIG or stick welding because sparks can land in your lap and burn, rather than just bouncing off and falling down if you were standing. Instead, if you can’t sit, try to lean a hip, shoulder or elbow against something for that added stability.

Welding might not be the comfiest thing you’ve ever done, but there are a few things you can do that will make a job feel a lot better.

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1. Clean your metal

When it comes to how clean your workpiece is, TIG is the most unforgiving. Any kind of rust, paint, oil or otherwise that hasn’t been wiped or ground off your base metal can seriously impact your weld, and not in a good way.

Go over your workpiece with a grinder or a wire brush to get rid of almost everything that is going to cause issues. Then you can give your material a good wipe down with acetone or a low VOC cleaner.

Don’t use a heavy-duty cleaner; even after it has dried, residue remains on the surface of your metal. This residue will give you a dirty weld, and you’re probably going to create mustard gas as you try and burn through it.

2. Use the right tungsten & prep

Not every tungsten is suited to every metal, so it’s important to pick a tungsten that will work well with the base metal. For example, a gold-tipped Lanthanated tungsten is a great all-rounder, but if you were working with only aluminium, a white-tipped Zirconiated tungsten would be better.

The other thing that will improve your weld is how you prepare your chosen tungsten. You almost always want to grind your tungsten to a point, and you always want to grind lengthways.

If you grind your tungsten in a horizontal position to the wheel, you end up including more grooves across the top, which the arc has to navigate. Grinding lengthways, so the grain runs in the same direction as the whole tungsten, will give you a more focused arc.

Keeping a separate, dedicated tungsten grinder (preferably with a diamond wheel) will also help to keep your tungstens from picking up contaminants from anything – like steel or stainless shavings – that are still present.

3. Feeding your filler

A great way to improve your TIG is by practising your wire feeding. There’s a couple of ways to add filler, but one good technique is to hold it like a pen or pencil.

Rest the wire on top of the middle finger, pinched between forefinger and thumb (with the thumb further back). Push it through by bending back the forefinger and middle finger down the rod and then pushing them forward, dragging the filler metal with them, using the thumb as a guide or to help if necessary.

You can make your feeding a lot easier if you don’t hold too far up the rod. Having roughly 10cm of rod out in front of your fingers is ideal; otherwise, you could lose control as it wobbles around.

To get an even looking weld, it’s also good to try and dab an equal amount of filler into the pool each time. A good rule of thumb for adding filler wire to your weld pool is to dab the width of your rod. If you have 1.6mm thick filler, you want to add roughly 1.5mm into the pool.

4. Don’t melt the filler rod directly

By ‘directly’ melting the filler, you’re using the heat of the tungsten or the arc to melt the filler metal. Your filler rod shouldn’t be balling or ballooning at the tip.

Using the arc to melt your metal won’t give very good fusion, as the metal often ends up sitting on top of the workpiece rather than actually building up the joint. You want to be pushing your filler into the weld pool, as it’s the hot pool that then melts it.

5. Keep your tungsten clean

Dipping is natural. Whether you’ve gotten too low and put your tungsten into the weld pool or you got too close with the filler rod and touched it against the tungsten, everyone does it. The most important thing is to make sure you clean it as soon as it happens.

If you’ve dipped your tungsten, you’ll need to pause your weld and regrind it to remove the contaminants. Unfortunately, once it’s been dipped, you can’t just burn that extra metal off, and if you do, it’s going straight into your weld, where it’ll cause issues.

If you don’t want to stop what you’re doing to regrind your tungsten, having some pre-prepared tungstens on the side makes it easy to swap tungstens on the go. Then, when you’ve finished your weld, you can regrind any that need cleaning in one go.

6. To gas or not to gas?

Getting ample gas coverage for your weld makes a world of difference to the final result, so why not just crank it up all the way? Wouldn’t that be best? No, it wouldn’t. Having too much gas is actually bad.

If you’ve got your gas flow all the way up, it creates turbulence, which destabilises your arc. Not to mention, pouring unnecessary gas over your weld is wasteful, and you’ll need to replace your cylinders more often.

Stick to the recommended gas flow rates; we recommended 8-12L/m, and if you do need more, just go up a little bit at a time.

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1. Earth clamp

Make sure you have a good earth. Like welding, plasma cutting machines come with a torch and an earth clamp, as you need to complete the electric cycle to ignite an arc.

You want to attach the clamp to a clean section of your workpiece. When you attach it to the workpiece, make sure it’s not the part coming off, as you’ll break the cycle, and the arc will cut out. If you’ve got a bad ground (dirty metal, not close enough, etc.), it can affect the cut quality.

2. Cutting distance

Contact cutting tips are dragged along the surface of the metal as they go to create the cut. This often means that they wear out faster, as they’re directly exposed to any spark splashback or any stray metal going flying.

If you can, use a ‘stand off’ shield on the torch, this will hold your torch at a good height off the metal consistently and can help with the movement.

Every UNIMIG plasma cutting machine comes with a torch that has a stand off shield option, which extends the life of your consumables.

If you’re trying to cut through the max metal thickness your machine can do, having the tip flush against the metal can be more helpful, but in general, leave a bit of space.

3. Amps & Travel speed

When it comes to plasma cutting, your amps and travel speed impact each other. Technically, you could have your machine set to run its max amps for every single cut, and all you would adjust is the travel speed.

Running at full power all the time probably isn’t the best for your torch, so if you’re cutting thinner metal (like sheet metal), then turning your amps down to match that will still give you a good cut, you’d just slow down a bit. How do you know what’s a good travel speed though?

A good travel speed will mean that the sparks fly straight down from the cut, and your torch is running smoothly over the metal.

If you’re going too fast, you’ll have sparks flying back at you from the top of the cut because it’s bouncing off the metal that isn’t being entirely cut through.

If you’re travelling too slowly, the sparks will still shoot out from the bottom, but you’ll find that the torch gets stuck because more dross (the excess melted metal) builds up.

Find a good travel speed that matches your amperage.

4. Sample runs

Doing a sample run along a piece of metal that is the same thickness as the one you’re planning to cut will help you perfect your travel speed. When you go to do the actual cut, you’ll have no issue and a clean cut with minimal cleanup.

5. Consumables

One of the main things that can impact a cut is the consumables inside your torch. It’s good to get into the habit of checking over your torch before you start cutting, as you’ll want to clean or replace any dirty or damaged consumables.

For example, metal slag covering any of the air holes, chipped, burnt or notched nozzles and electrodes will all lower the quality of your cut.

The other thing to keep in mind with consumables is making sure that they can handle the amps. If your plasma cutter maxes out at 80 amps, but your consumables are rated for a max of 60 amps, you’re going to burn through them fast.

Get consumables that are compatible with each other and your machine.

6. Dry runs

As well as sample runs to check your settings, doing a dry run to make sure you can reach the whole way and be comfortable are also recommended.

While you can technically pause in the middle of a cut, you’re going to be left with a hole at the point where you restart. Checking that you can run the entire length of the cut without issue doesn’t hurt and will keep you from making any gaping craters in a piece that you had to stop and reposition on.

7. Perfect Your Shape

Freehand plasma cutting is fine, and it works, and if you’re cutting a squiggle, then it’s your only option. But, if you want straight lines or perfect shapes, then using a guide, stencil or other bits of metal for perfect lines is definitely recommended.

For straight lines, clamp down a straight-edged piece of metal next to where you’re planning to cut so that you can press the torch up against it. It’ll ensure that you get a dead straight line without wobbles.

For circles, UNIMIG has a circle cutting guide available for purchase that you can attach to the torch to get perfect circles.

Check out the circle cutting attachments here.

8. Don’t start from the middle of the plate

Where possible, start your cut from the edge of the metal. If you start over the metal, the sparks blow back into the torch as it’s trying to burn through the metal, which damages your consumables.

If you have to start from the middle, angle the torch (roughly 45°) until it’s gone through and then reposition to 90° (or square) against the metal for the rest of the cut. Angling the torch means that when the sparks blow up, they’ll fly past the torch tip rather than into it.

9. Cleaning

Give your metal a quick clean and make sure there’s no burs or rough spots that the plasma torch will catch on; you’ll get an uneven cut that will need work to make it smooth. Checking for any bumpy patches on the metal you’re using for a guide (if you’re using one) is also a good idea.

You don’t want to be following a straight line and then find that it’s actually got a few hills and dips that have now transferred to your cut.

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What is a HYPERARC 16TC?

To start, let’s run through what exactly we mean by a 16TC. ‘16TC’ is short for a 7016 twin coated electrode. Now you might be thinking, ‘Great. What exactly is a 7016 electrode? Why’s it twin coated?’

Stick electrodes have a set coding system, where the first two numbers (70) represent the tensile strength, the third number (1) represents the positions it can be used in, and the fourth number (6) represents the type of coating on the outside of the filler metal.

In the case of a 7016, it has a tensile strength of 70,000, it can be used in all positions (except vertical down), and it has an outer coating that is low in hydrogen.

7016 stick electrodes produce a high-quality weld and are often used for structural applications. They’ll weld onto all carbon steels though, so don’t feel like you’re limited to using them on buildings.  

While the 7016 electrodes, in general, are a great electrode, our HYPERARC 16TCs take it to the next level with all the added benefits of twin coating.

Twin Coating

Most stick electrodes are single coated, which means that all the ingredients needed to be both conductive and protective are included in the same outer layer that covers the inner core. However, you can purchase twin coated electrodes, and these are precisely what they sound like: electrodes with two layers.

The inner layer contains the ingredients that ionise and make it conductive and the outer layer, which is non-conductive, contains the shielding and slag forming components.

The separation of the two layers means the electrode has an extremely stable, concentrated arc which is easy to direct.

The twin coating isn’t the only thing that makes the HYPERARC 16TCs a superior electrode, though.

What’s so great about our HYPERARC 16TCs?

Easy releasing slag

Every stick electrode leaves behind a topcoat that needs to be removed once you’ve finished your weld; it’s why stick welding doesn’t need gas. The problem is that some electrodes have difficult slag.

With the HYPERARC 16TC, you won’t need to spend ten minutes hammering at it with your chipping hammer only to have small chunks leftover. The easy releasing slag means a few taps with a hammer will have it practically falling off the weld, so you won’t have to spend as much downtime cleaning up.

Low spatter

Spatter is the small beads of molten metal that fly out from your weld and leave a mess around your final product. Thanks to the more stable and concentrated arc created by the twin coating, the HYPERARC 16TCs produce less spatter as you weld.

Less spatter means less clean up, so not only will you not be hammering away at hard slag, but you also won’t have to spend nearly as much time brushing or grinding away spatter to have a nice-looking weld.

Easy arc ignition & restrike

Trying to light a stick electrode is kind of like trying to light a match. You have to strike it against the metal with enough force that it’ll light, and then pull away just enough that the arc stays ignited, but you don’t get your electrode stuck to the metal.

Learning how to do this in one swift motion can be a bit of a challenge. With a HYPERARC 16TC, you eliminate the frustration of trying to ignite a difficult electrode; striking and restriking your arc is easy.

Low amp capable

While some electrodes can struggle to maintain a steady arc on low amps, this is not the case for our HYPERARC 16TC. High amps or low, the 16TC will keep its stable, concentrated arc for a penetrative weld on any material thickness.

AC & DC compatible

Not every electrode will work on AC, but this isn’t true for the HYPERARC 16TC. It’s compatible with both AC and DC currents (positive and negative), making it a versatile electrode that’ll work with every machine you have.

Low Hydrogen

There are a lot of things that can cause contamination in a weld. There are outside atmospheric gases that can cause it, dirt or otherwise left on the metal can contaminate it.

If you go a little wild with your weld technique and start weaving your slag into the joint, you’ll contaminate it. Moisture will also cause contamination in the weld, and you’ll have to redo it.

With a low hydrogen electrode, there’s no moisture in the electrode, which means there’s no risk of contamination from the electrode itself.

Vacuum-sealed

Our HYPERARC 16TCs come in vacuum-sealed packaging in order to keep them moisture-free. There’s no chance of moisture re-entering the electrode during transportation from manufacturer to you, so you can use them straight out of the box without any worries.

No matter what you plan to use them for, the UNIMIG HYPERARC 16TC Low Hydrogen Electrodes are a perfect fit for all your steel welding needs.

UNIMIG sells a range of HYPERARC electrodes that include general-purpose, low hydrogen, stainless steel, hard facing and cast-iron electrodes.

Check out the full product page here: HYPERARC 16TC

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Torch Sizes

TIG torches come in a number of set sizes: 9, 17, 18 & 26.

These, generally, are in numerical order, in that 9 is the smallest size torch and 26 is the largest. ‘Generally,’ because the size 20 torch is the water-cooled version of the size 9 (but UNIMIG doesn’t sell that torch). The size 18 torch is the same as the size 17, but it is also water-cooled rather than air-cooled.

The smaller the torch you purchase, the lighter it will be, but the hotter it will get at higher amps. Professional welders often prefer a lighter torch so that they can weld for longer before their hand gets fatigued. On the flip side, the bigger the torch, the higher amperage you can run it at. A size 26 torch can use more power and stay cooler for longer than a size 9.

Each torch uses the same types of consumables, which each have their own sizes that fit inside when put together. A size 9 torch will have much smaller consumables than a size 26, meaning you can’t mix and match.

Arc Torchology

UNIMIG Arc Torchology TIG Torches are our very own home-grown torches. They follow the same sizing pattern as standard TIG torches. Keep in mind that the consumables used for these torches aren’t compatible with any others, so if you’ve got an Arc Torchology torch, you’re going to need the specific consumables designed for it. There’s good news, though, as these torches come with some added bonuses you won’t get from a standard torch.

The consumables used have up to 20x longer life with better performance than standard TIG torch consumables. While it’s not an option to mix and match between brands, why would you want to when UNIMIG consumables last longer, meaning you’ll be spending less in the long run with less replacements needed.

On top of great consumables, a few technologies are employed in every Arc Torchology torch that really add the cherry on top.

Force cool technology: a highly effective series of passages and wells force cool the collet, maximising conductivity and extending consumable life.

Heat zone technology: transferred heat from the ceramic cup is isolated by a unique external barrier resulting in cooler running torches with increased power to weight performance ratios.

Tungsten release system technology: trouble-free extension of the electrode with a 180° twist of the back cap. There is no need to remove any other wear parts to extend the electrode.

Bi-flow technology: high-capacity cooling chambers remove excessive heat at source, allowing greater performance from a smaller body. Bi-flow is only available on the water-cooled T3W.

Air vs Water-Cooled

This one is pretty self-explanatory. Air-cooled torches are cooled by air (with a fan inside the machine), and water-cooled welders are hooked up to a water-cooler unit. Water-cooled torches have a higher duty cycle and so will last longer before heating up.

Duty Cycle

Duty cycle is measured in 10-minute increments, so if you have a 60% duty cycle, you’ll have 6 minutes of constant use and then 4 minutes cooldown time. Welding torches have their own duty cycles that are separate from the machines.

Torch duty cycles are much higher than a machine’s, though, so you’ll pretty much never have to worry about your torch overheating before your machine. The only way you’d manage something like that is if you were to attach, say, an SB15 torch (max 180A) onto a Razor 500 Welder set to its max 500 amps.

If a torch does overheat, it won’t shut off like the machines do; the consumables inside it will just start burning up, as there’s no thermal overload protection on them.

The other difference between the duty cycle listed on a UNIMIG machine and a UNIMIG torch is that the machine’s duty cycle is its performance at the maximum amps.

In contrast, a torch can run on higher amps than what is listed. The listed duty cycles on the torches are the recommended max amps they should be used at (and are roughly 75% of the max power of the machines they’re paired with), but they can all run at higher amps.

This does affect the duty cycle, which will get lower the more you up the amps. Even with a lowered duty cycle, a torch will still last longer than the machine.

There’s a good reason for the way every machine is paired up with its torch, and the torch provided will always be able to handle whatever the machine is pumping out. You don’t have to stress about whether the torch is the right match for your welder.

Arc Torchology® TIG Torches

ARC TORCHOLOGY T2 TIG Torch

• Air-cooled
• Tungsten electrode size 1.0mm-3.2mm
• Dinse size 35/50
• DC duty cycle: 35% @ 190A
• AC duty cycle: 35% @ 135A
• High Frequency

Besides all the benefits of the Arc Torchology line, the T2 is the same size as an SR17 with the performance of an SR26.  You get more bang for your buck and more power in a smaller gun.

View more info: T2 TIG Torch

ARC TORCHOLOGY T3 TIG Torch

• Air-cooled
• Tungsten electrode size 1.6mm-3.2mm
• Dinse size 35/50
• DC duty cycle: 35% @ 240A
• AC duty cycle: 35% @ 170A
• High Frequency

The T3 is the same size as the SR26, but it comes with 30% more power than it, plus all the other great parts of being an Arc Torchology gun.

View more info: T3 TIG Torch

ARC TORCHOLOGY T3W TIG Torch

• Water-cooled
• Tungsten electrode size 1.6mm-3.2mm
• Dinse size 35/50
• DC duty cycle: 100% @ 400A
• AC duty cycle: 100% @ 280A
• High Frequency

The T3W is the same size as the T2 and is water-cooled (the W stands for water). You’ll need to purchase a water-cooling unit for this torch.

View more info: T3W TIG Torch

High Frequency TIG Torches

SR9 TIG Torch

• Air-cooled
• Tungsten electrode size 1.0mm-3.2mm
• Dinse size 35/50
• DC duty cycle: 35% @ 125A
• AC duty cycle: 35% @ 90A
• High Frequency

View more info: SR9 TIG Torch

SR17 TIG Torch

• Air-cooled
• Tungsten electrode size 1.0mm-3.2mm
• Dinse size 35/50
• DC duty cycle: 35% @ 150A
• AC duty cycle: 35% @ 105A
• High Frequency

View more info: SR17 TIG Torch

SR26 TIG Torch

• Air-cooled
• Tungsten electrode size 1.0mm-3.2mm
• Dinse size 35/50
• DC duty cycle: 35% @ 180A
• AC duty cycle: 35% @ 125A
• High Frequency

View more info: SR26 TIG Torch

SR18 Water-Cooled TIG Torch

• Water-cooled
• Tungsten electrode size 1.0mm-3.2mm
• Dinse size 35/50
• DC duty cycle: 100% @ 380A
• AC duty cycle: 100% @ 270A
• High Frequency

View more info: SR18 Water-Cooled TIG Torch

These torches are your standard, run of the mill, High Frequency (HF) TIG torches, which use standard interchangeable consumables. The main differences between these torches are how big they are (which affects how big your electrode can be) and their max amps/duty cycle. If you’re looking to get the water-cooled SR18, don’t forget that you’ll need to purchase the water-cooling unit as well.

Valve TIG Torches

9V TIG Torch

• Air-cooled
• Tungsten electrode size 1.0mm-3.2mm
• Dinse size 10/25 or 35/50
• DC duty cycle: 35% @ 125A
• AC duty cycle: 35% @ 90A
• Valve (lift arc)

View more info: 9V TIG Torch

17V TIG Torch

• Air-cooled
• Tungsten electrode size 1.0mm-3.2mm
• Dinse size 10/25 or 35/50
• DC duty cycle: 35% @ 150A
• AC duty cycle: 35% @ 105A
• Valve (lift arc)

View more info: 17V TIG Torch

26V TIG Torch

• Air-cooled
• Tungsten electrode size 1.0mm-3.2mm
• Dinse size 35/50
• DC duty cycle: 35% @ 180A
• AC duty cycle: 35% @ 125A
• Valve (lift arc)

View more info: 26V TIG Torch

These torches are your everyday, standard valve TIG torches. Like the HF torches, the main differences between these three are the size and the max amps/duty cycle. Instead of pressing a button, these torches work by twisting the valve to let the gas flow. There is no water-cooled version of a valve torch.

Every UNIMIG AC/DC TIG welder comes with a T2 or T3 torch.

If you’ve purchased a 3-in-1 multi-process welder, these only come with a MIG torch and stick electrode holder, so you’ll need to buy a separate TIG torch that has a matching dinse size (otherwise, it won’t plug in) and a high enough amperage level.

Personal preferences about how big you want the torch will also influence your decision, but keep in mind that these multi-process machines are not compatible with HF torches. You’ll have to purchase a valve torch.

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Binzel vs Bernard vs Tweco

What’s the difference? The main difference between the three is the original manufacturers of each. Tweco was born out of a basement in 1936, Binzel popped up in 1945, and Bernard joined the scene in the 1950s. Since then, they’ve dominated the welding industry with their three styles of MIG torches.

The other difference is their consumables. Despite the fact that these three guns look almost identical, the consumables inside them are not interchangeable.

Every UNIMIG MIG welder comes with a Binzel style torch, so you’d need to buy Binzel style consumables. They’re all basically the same thing, but slight differences in the gun models mean that a Binzel consumable won’t fit into a Tweco gun and vice versa.

Air vs Water-Cooled

This one is pretty self-explanatory. Air-cooled torches are cooled by air (with a fan inside the machine), and water-cooled welders are hooked up to a water-cooler unit. Water-cooled torches have a higher duty cycle and so will last longer before heating up.

Duty Cycle

Duty cycle is measured in 10-minute increments, so if you have a 60% duty cycle, you’ll have 6 minutes of constant use and then 4 minutes cooldown time. Welding torches have their own duty cycles that are separate from the machines.

Torch duty cycles are much higher than a machine’s, though, so you’ll pretty much never have to worry about your torch overheating before your machine. The only way you’d manage something like that is if you were to attach, say, an SB15 torch (max 180A) onto a Razor 500 Welder set to its max 500 amps.

If a torch does overheat, it won’t shut off like the machines do; the consumables inside it will just start burning up, as there’s no thermal overload protection on them.

The other difference between the duty cycle listed on a UNIMIG machine and a UNIMIG torch is that the machine’s duty cycle is its performance at the maximum amps.

In contrast, a torch can run on higher amps than what is listed. The listed duty cycles on the torches are the recommended max amps they should be used at (and are roughly 75% of the max power of the machines they’re paired with), but they can all run at higher amps.

This does affect the duty cycle, which will get lower the more you up the amps. Even with a lowered duty cycle, a torch will still last longer than the machine.

There’s a good reason for the way every machine is paired up with its torch, and the torch provided will always be able to handle whatever the machine is pumping out. You don’t have to stress about whether the torch is the right match for your welder.

Binzel Style MIG Torches

SB15 BINZEL Style MIG Torch

• Air-cooled
• Wire size 0.6mm-1.0mm
• CO2 duty cycle: 60% @ 180A
• Mixed Gas duty cycle: 60% @ 150A

View more info: SB15 BINZEL Style MIG Torch

SB24 BINZEL Style MIG Torch

• Air-cooled
• Wire size 0.6mm-1.2mm
• CO2 duty cycle: 60% @ 250A
• Mixed Gas duty cycle: 60% @ 220A

View more info: SB24 BINZEL Style MIG Torch

SB25 BINZEL Style MIG Torch

• Air-cooled
• Wire size 0.6m-1.2mm
• CO2 duty cycle: 60% @ 230A
• Mixed Gas duty cycle: 60% @ 200A

View more info: SB25 BINZEL Style MIG Torch

SB36 BINZEL Style MIG Torch

• Air-cooled
• Wire size 0.8mm-1.2mm
• CO2 duty cycle: 60% @ 300A
• Mixed Gas duty cycle: 60% @ 270A

View more info: SB36 BINZEL Style MIG Torch

SB38 BINZEL Style MIG Torch

• Air-cooled
• Wire size 1.0mm-1.6mm
• CO2 duty cycle: 60% @ 340A
• Mixed Gas duty cycle: 60% @ 300A

View more info: SB38 BINZEL Style MIG Torch

SB500 Water-Cooled BINZEL Style MIG Torch

• Water-cooled
• Wire size 1.0mm-1.6mm
• CO2 duty cycle: 100% @ 500A
• Mixed Gas duty cycle: 100% @ 450A

View more info: SB500 Water-Cooled BINZEL Style MIG Torch

Our MIG welders come packaged with torches that are capable of handling the max amps they’re putting out, so if you’re buying your first welder, you won’t need to stress too much about which torch is going to be the best for you. We’ve already done the work for you and selected a torch that will suit the machine, and therefore should suit your needs as well.

However, if you are looking to swap torches, keep in mind which wire sizes you’re going to need and the fact that you’ll also need consumables to match whichever torch you get.

One of the reasons you might look to get a new torch or upgrade from what you currently have is to swap from air-cooled to water-cooled. A water-cooled torch will run pretty much indefinitely (though your machine won’t), but you will need to purchase the water-cooling unit the torch connects to separately.

While every MIG welder at UNIMIG comes with a Binzel style torch, we also sell Tweco and Bernard style torches for those who prefer them.

Spool Guns

A spool gun is a pistol grip gun with a compartment for a wire spool roll to be attached directly onto the gun. They’re designed specifically for welding aluminium, as it’s a much softer wire, so only having to feed it through the gun and straight into the weld pool saves you from the otherwise, often infuriating process of trying to weld aluminium.

150 AMP Spool Gun

• Air-cooled
• Wire size 0.8mm-1.0mm
• CO2 duty cycle: 60% @ 150A
• Mixed Gas duty cycle: 60% @ 130A

View more info: 150 AMP Spool Gun

220 AMP Spool Gun

• Air-cooled
• Wire size 0.8mm-1.2mm
• CO2 duty cycle: 60% @ 220A
• Mixed Gas duty cycle: 60% @ 200A

View more info: 220 AMP Spool Gun

These two guns can both only carry a 1kg wire spool, so the one difference between the two is how many amps they output, and therefore how thick your filler wire can be. Because the spool gun feeds the wire directly through the torch, your drive rollers are located in the gun. You’ll need to make sure that the roller size matches your wire size.

Push-Pull Guns

Push-Pull guns are similar to spool guns in that they’re designed to make welding aluminium easier. A Push-Pull gun works by having a small, second motorised wire feeder directly in the gun. This motor works in harmony with the feeder inside the machine, and together they achieve a smooth feed as the machine pushes the wire through the torch lead and the gun pulls it through from the other end.

300 AMP Push-Pull Gun

• Air-cooled
• Wire size 0.8mm-1.2mm
• CO2 duty cycle: 60% @ 300A
• Mixed Gas duty cycle: 60% @ 270A

View more info: 300 AMP Push-Pull Gun

400 AMP Water-Cooled Push-Pull Gun

• Water-cooled
• Wire size 1.0mm-1.6mm
• CO2 duty cycle: 100% @ 400A
• Mixed Gas duty cycle: 100% @ 350A

View more info: 400 AMP Water-Cooled Push-Pull Gun

Because there’s an internal wire drive system in the gun, there are small rollers inside it. Like the spool gun, make sure you match the rollers to the wire size you’re using.

The Push-Pull guns have a Euro connection, too; however, they also come with a ‘pinout’ connection. Only a few machines have corresponding pinholes that will fit these pins, so Push-Pull guns are considered more ‘specialised’ than a spool gun.

The advantage of them, though, is that while they’re still a hefty gun, there isn’t an entire kilo resting on your hands. Plus, you can use standard sized spools so you can weld for longer.

The Push-Pull guns also have an 8-metre long lead (double the size of a standard MIG torch), giving you extra flexibility.

If you prefer the water-cooled version, you’ll need to purchase the water-cooling unit that the torch connects to separately.

Liners

A liner guides your wire inside the torch, and it ensures the wire makes it out of the torch tip. You may need to change your liner before you feed your wire through, as these liners – much like the rollers – will only fit specific sizes. There are separate liners for steel wires and aluminium wires.

Steel liners are fairly straight forward; they just need to match the wire size and can be inserted into the torch lead as they come.

If you’re going to use a standard MIG torch for an aluminium wire, you’ll need a teflon liner. These liners will need a neck spring attached to the top before they’re inserted. The neck spring keeps the liner ridged so it can be fed into the torch with no issues and keeps the wire from kinking.

Because there are several liner types and thicknesses, they’re colour-coded to make it easier for you.

When purchasing the liners that you’ll need, make sure it’s the correct length for your torch, as they come in 3, 4 and 5 metres.

The wire sizes on the MIG torches are recommendations rather than strict guidelines, as you can insert most liners into the torch hoses. The problems arise if you put too thick a wire in a lower amperage machine. For example, if you were to try and weld 1.2mm thick filler wire with the Viper 182 Mk II, it wouldn’t melt properly, as its max amps (180) aren’t enough to heat it all the way through.

On the other hand, if you had a Razor 500 SWF, which comes with the SB38 torch, you could still use 0.6mm wire. The recommended is for 1.0mm-1.6mm; however, you can turn the amps on the machine low enough that you won’t just vaporise the wire as it feeds out of the torch. For all of these applications, make sure you have a liner size that matches your filler wire.

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So, what do you need to get to get started with your plasma cutting?

Air Compressors

Plasma cutters in Australia are made to work on compressed air only, including UNIMIG machines. If you want to plasma cut, you’re going to need an air compressor to connect to your machine.

When purchasing a compressor, make sure to get one that can deliver 70–120psi and has an airflow/intake volume rating that is greater than your plasma cutters.

Your plasma cutter will state the litres per minute (L/min) it uses, so you’ll want a compressor that states a higher number than that. You don’t want to run out of air before you’ve finished your cut.

You can also buy plasma cutters that have a built-in air compressor. There are benefits to both options, so you’ll need to consider before deciding which will work best for you.

Unfortunately, UNIMIG doesn’t sell air compressors, so you’ll need to visit your local hardware store once you’ve bought a plasma cutter.

Clean Cut vs Severance

You can get two types of cuts with your plasma cutter: a clean-cut or a severance cut.

Clean cut: a smooth, clean-cut through the metal.

Severance: a cut all the way through, but it won’t be smooth or pretty, and if you plan on working on it after, you’ll need to clean it up.

Usually, every plasma cutter will have a maximum clean cut thickness and a maximum severance it can do. These indicate how thick the metal can be if you want a good quality cut and how thick the metal can be if all you need is to get through it. The severance thickness will always be more than the clean-cut thickness. These cut depths will also change depending on the metal type.

Back Arc vs High Frequency

There are two arc ignition types when it comes to plasma cutting, though both are considered ‘pilot arc’.

The first is High Frequency (HF). A HF plasma torch needs to be in very close proximity for the arc to spark and begin the ionising process. The arc jumps from the torch to the metal, and HF torch consumables generally wear out faster because of this.

The second type is Back Arc Strike. A torch will start up automatically with just the touch of a button through a spring-loaded design inside the torch head. The benefit of a back arc start is that it’s a lot more user friendly. It doesn’t matter if your metal is rusty or otherwise not clean; a back arc torch can cut straight through all of it. CNC table plasma cutting torches are also back arc strike ignition.

The back arc strike torches are much more common and popular these days, as HF torches run the risk of disrupting sensitive equipment that might be nearby, such as hospital machinery and computers.

Every UNIMIG plasma cutter comes with a back/pilot arc capable torch.

Plasma Cutters

VIPER CUT 30 Mk II Plasma Cutter

• Comes with an SC30 Plasma Torch
• CNC connection
• Pilot Arc start
• 12mm Clean Cut
• 14mm Severance
• Duty cycle: 15% @ 30A
• Gas flow: 170L/min
• 10 AMP plug

Like our welding machines, UNIMIG also has a VIPER version plasma cutter. It’s lightweight, with a 10 AMP plug, so you won’t have trouble finding a socket, making it perfect for home DIY projects or for taking offsite. It can clean cut through over 10mm of steel, which is pretty thick metal when you think about it. The Viper Cut 30 Mk II machine comes with the SC30 torch and a CNC connection port, so it’s perfect for every use case.

View more info: VIPER CUT 30 Mk II

RAZOR CUT 40 AIR Plasma Cutter

• Comes with an SC80 Plasma Torch
• Built-in air compressor
• Pilot Arc start
• 10mm Clean Cut
• 12mm Severance
• Duty cycle: 25% @ 40A
• Gas flow: 120L/min
• 15 AMP plug

The main feature the RAZOR CUT 40 Air has is it comes with a built-in air compressor. It has more portability than any of our other plasma cutters, and you won’t need to go out and buy an air compressor. It still requires a power source, a 15 AMP one at that, because it needs the electricity to run the added component that’s inside and ignite an arc. The built-in compressor means that if you’re planning on doing outdoor work, or any work that’s going to need distance from where you’d place an air compressor, this is the machine for you. It has the option of an external connection, so if you need a thicker cut, you can get a separate air compressor and make thicker cuts.

View more info: RAZOR CUT 40 AIR

RAZOR CUT 45 Plasma Cutter

• Comes with an SC80 Plasma Torch
• CNC connection
• Pilot Arc start
• 16mm Clean Cut
• 20mm Severance
• Duty cycle: 25% @ 45A
• Gas flow: 189L/min
• 15 AMP plug

View more info: RAZOR CUT 45

RAZOR CUT 80 Plasma Cutter

• Comes with an SC80 Plasma Torch
• CNC connection
• Pilot Arc start
• 30mm Clean Cut
• 35mm Severance
• Duty cycle: 40% @ 80A
• Gas flow: 189L/min

View more info: RAZOR CUT 80

RAZOR CUT 120 Plasma Cutter

• Comes with an SC120 Plasma Torch
• CNC connection
• Pilot Arc start
• 45mm Clean Cut
• 60mm Severance
• Duty cycle: 60% @ 120A
• Gas flow: 189L/min

View more info: RAZOR CUT 120

These machines are generally the same, with the exception being their max amps and, therefore, their max cutting thicknesses. These are usually recommended for a workshop or professional environment because of the power they require, but the 45 comes with a 15 AMP plug. This is great because you can easily get one of those for your home, and then you can hook it up to a CNC table. The CNC connection is one of the coolest features on all three of these machines, and it’s available on the 45, 80 and 120.

Plasma Torches

SC30 Plasma Torch

• Stand off cutting

View more info: SC30 Plasma Torch

SC80 Plasma Torch

• Contact cutting
• Stand off cutting
• Gouging

View more info: SC80 Plasma Torch

These torches come with their respective machines, and they vary in terms of the pin setup that plugs into the machine, so you’ll need to keep that in mind if you want to swap to a HF torch. When you’re buying a machine and torch, make sure you get one that has the type of consumables you want, as there are a few types of cutting available. Stand off cutting is the most common, and it gives your consumables the longest life.

SCM80R Plasma Torch

• Duty cycle: 60% @ 80A
• Pilot Arc

The SCM80R is a CNC specific torch. It is designed for use on a CNC plasma table. If you’ve purchased a plasma cutter that can connect to a CNC table, then you’ll likely also need a torch that is compatible as well. Unfortunately, the only thing we don’t sell is the actual CNC table itself. However, if you’ve got one available to you, we’ve got all the parts you’ll need to get it up and running.

View more info: SCM80R Plasma Torch

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Quick Navigation

Jump to:

• Machine Setup
• Torch & Consumables
• Settings
• Making the Cut

What is Plasma Cutting?

Plasma is a super-heated column of gas (and the fourth state of matter). It’s formed when compressed air or compressed gases (like nitrogen or argon) make contact with the electrode (which is inside the torch) and ionise to create plasma.

Plasma cutting (plasma arc cutting), therefore, is a melting process that uses plasma and an outside power source to create an electric arc between the electrode and the metal being cut to melt and eject it from the cut.

Plasma can cut through anything electrically conductive; steel, stainless steel and aluminium are all fair game. In comparison, oxy cutting will only work on metals that contain iron, as it works through chemical reactions, such as oxidisation (it’s like a sped-up version of rusting) instead.

Machine Setup

1. Air/Gas
2. Torch & Consumables
3. Settings

1. Air/Gas

Unlike welding machines, every Australian market plasma cutter you can buy is made to work on compressed air only, including UNIMIG machines.

The good news is that an air compressor attaches to the back of a plasma cutter in the same way a gas tank connects to the back of a welder. The bad news is that UNIMIG doesn’t supply air compressors, so you’ll have to purchase one separately from your local hardware store.

The need for an air compressor means they’re not very portable because you need to be connected to the compressor and a power supply. When purchasing a compressor, make sure to get one that can deliver 70–120psi and has an airflow/intake volume rating that is greater than your plasma cutters. You don’t want to run out of air before you’ve finished your cut.

If you’re looking for more portability, some machines come with built-in air compressors, like the RAZOR CUT 40 AIR Plasma Cutter. These machines will still need a power supply, however.

An air dryer or filter is essential for keeping contaminants like moisture and dust particles out of the machine’s air lines. Moisture in the pipes will come out in your torch and cause your consumables to burn up faster, resulting in bad cuts, which is something you’d like to avoid.

Depending on which model machine you have, your air dryer/filter can be found inside the machine or at the back of the machine.

3 types of filter

• Basic
• Roll
• In-line

Basic: most plasma cutters will come with a basic air filter. These will work fine, especially if you’re only doing small cuts on hobby projects, but additional, higher quality air filters are still recommended. If you choose to upgrade your air filter, the original basic filter will remain attached to your machine, and the new filter is attached as an extra unit. Basic air filters are self-draining, with a small hose that sticks out the bottom for the captured moisture to drip out. Some UNIMIG machines have this basic air filter installed inside the machine, but these come with a drainage hole drilled in the bottom to work in the same way.

Roll: these filters look similar to a toilet roll, which is where they get the nickname ‘toilet roll filters,’ and consist of a cylindrical cartridge. The roll works well, but it’s not self-draining, which means they need to be changed every so often depending on the frequency of use.

In-line: these sound cool, but in reality, they’re not that good. Made from specially treated plastic, it works by closing up when moisture touches it to block the water from getting through. The problem? Airflow is one of the most important things when running a successful plasma cut, and these filters block the moisture as well as the airflow when they close.

Both roll and in-line filters are mostly needed in high humidity environments.

2. Torch & Consumables

Plasma cutting is done in DCEN (Direct Current Electrode Negative). Getting the polarity correct on your plasma cutter is a lot easier than any form of welding because the plasma torches have a different shaped plug.

There’s no guesswork involved with this one; you literally can’t connect your earth clamp or torch into the wrong hole.

Quick Tip: don’t clamp your earth to the bit of metal that will be cut off, as you could then become the path of least resistance, which is not a good time. Make sure to attach your earth clamp to either a (clean) metal workbench or the part of the metal that will not fall away once it’s cut.

Because plasma cutting machines come with a specific plug for the torch and only the Positive (+) polarity panel mount, you can’t use them for anything else, unlike welding machines, which are generally mix and match (to a degree).

Consumables

The attachments on your torch will make a significant difference to the type of cutting you can do with your machine.

Types of Shields

• Contact cutting
• Gouging
• Stand off cutting

Different guns will allow for more or less varieties of shields to be attached. For example, the UNIMIG SC30 Plasma Torch, which comes with the VIPER CUT 30 Mk II, can only do contact cutting and stand off cutting. In comparison, the SC80 Plasma Torch can do all three.

Contact cutting: contact cutting is what it sounds like; you place the tip of the gun against the metal you want to cut, and off you go. UNIMIG torches come with a contact cutting shield cap so that the cutting tip doesn’t touch the metal (as this can wear your tip out), but some machines don’t, in which case the tip itself will be pushed along the metal.

Gouging: gouging is used when you want to remove metal from a piece without actually cutting through it. It’s generally used to remove defective welds so that you can redo them.

Stand off cutting: stand off cutting is similar to contact cutting, except you are forced to leave a space between the torch and metal, as the shields come with little legs or small wheels known as ‘stand off guides’. This process gives your consumables extra life as they remain at a distance from the sparks.

In general, regardless of the type of cutting you want to do and the shield you attach for it, there are several consumables inside the gun which remain the same, though they may look slightly different.

Standard Consumables

1. Electrode
2. Swirl ring (gas distributor)
3. Cutting tip
4. Shield cap body (retaining cap)
5. Shield cap

Putting the consumables together to get your torch up and running isn’t too hard, and most machines will come with a guide either on the machine or in their User Manual. UNIMIG torches usually come already set up, but if you need to swap parts or replace them, you’ll need to take apart and reassemble the torch.

Consumables Assembly

1. Screw your electrode in
2. Place your swirl ring (gas distributor) on the torch head
3. Place your cutting tip over the electrode
4. Screw your shield cap body (retaining cap) in; this should go over the other parts and hold everything in place inside the torch
5. (If you have one) screw your shield cap onto the end of the shield cap body

The higher-end torches will also need a cooling tube. The tube sits inside the torch head, and the electrode is screwed on like normal over it.

If you haven’t assembled the torch correctly, you’ll know about it straight away, as it won’t turn on. Most of these consumables will sit in place, so don’t try and twist or force things in; you’ll just end up breaking parts.

The most important thing about the consumables is that you have the right ones for the type of cutting you want to do, and they’ll withstand the amps you’ll be using. These can all be changed and replaced as the need arises.

The small opening of your cutting tip shouldn’t touch the material you are cutting unless the torch is designed for the tip to make contact. A damaged contact tip will lower the quality of your cut. The cutting tip should also be able to withstand the number of amps output by the machine; otherwise, it will burn up. In both of these cases, you’ll need to replace your cutting tip.

You need to replace the electrode in your gun once there is around a 1mm pit in the centre of the piece.

It’s recommended to swap out your electrode and your cutting tip at the same time.

3. Settings

Amperage

Unlike welding, the amps you set your machine to will not affect your cut all that much, so long as you adjust your travel speed to compensate. You can set your machine to its max amps and cut every thickness of metal, but if your machine goes up to 80A and you’re cutting 2mm steel, you’re going to have to fly across the cut to avoid warping or completely melting the metal.

You’ll also need to make sure you’ve got consumables in your torch that can handle the amps you’re putting out. If you have a machine set to 80A with consumables only capable of handling 60A max, you’re going to burn through them.

Some machines come with amperage guides which you can use as a starting point. For example, the VIPER CUT 30 Mk II comes with a recommended settings guide in the User Manual.

Air Pressure

In general, the air pressure regulator can be found on the back of the machine above the air filter. The regulator will have a hose that runs in on one side and out on the other, with a twistable valve on top. This valve is how you change the air pressure, which you can see on the pressure gauge.

Most UNIMIG machines come pre-set at a pressure level that will work well regardless of the amperage, and the regulator is inside the machine. A good starting pressure regardless of the machine is 75psi.

The amps and air pressure do work together, so if you’re cranking your amps as high as they can go, you’ll want to up your air pressure as well. You don’t want one overpowering the other, as it’ll give you a poor-quality cut.

2T vs 4T

2T (two touch) means you will need to hold the button down while you cut. In 4T (four touch) mode you will only need to click the button to ignite the arc, and it will stay ignited until you click it again to turn it off. This setting works the same way that a welder’s 2T/4T setting works, but there’s no foot pedal option.

Air Test

The air test light looks like a gas bottle, and this will check that your air is flowing through the torch at the correct pressure.

Perforated Metal

This setting will have an image of a plasma cutter over a dotted line and will allow you to cut over mesh and other perforated metals. The torch arc will automatically cut out on standard settings if it can’t find metal to complete the electric circuit, so switching to this mode will keep your arc steady for a smooth cut. Otherwise, you’ll have to keep pulling the trigger to start the arc over and over.

Clean Cut vs Severance Cut

You can get two types of cut with your plasma cutter: a clean cut or a severance.

Clean cut: precisely what it says, a smooth, clean cut on the metal.

Severance: a cut all the way through, but it won’t be smooth, and if you plan on working on it after, you’ll need to clean it up.

Every plasma machine will have a maximum clean cut thickness and a maximum severance. These indicate how thick the metal can be if you want a good quality cut and how thick the metal can be if all you need is to get through it. The severance thickness will always be more than the clean-cut thickness.

The metal thicknesses will vary depending on how many amps you can use (your machine model will determine your max amps) and what kind of metal you’re using. Aluminium is the softest metal, steel is harder and stainless steel is the hardest of the three. Despite their hardness, aluminium and stainless steel have a higher viscosity (which is a fluid’s resistance to flow) than mild steel. Their max cutting thickness is usually smaller than steel’s max thickness because of their viscosity.

For example, if you were using a RAZOR CUT 80 Plasma Cutter, your thickness would look like this:

The max cut and severance thickness your machine can do should be included in the product information, so make sure you get one that will go through the metal you’re planning to cut.

Travel Speed

Your travel speed will depend on how thick the material is that you are cutting. The sparks should be coming out straight down on the other side of the plate when travelling at the correct speed.

If you’re cutting too fast, the sparks will spray at a very steep angle in the opposite direction than you’re cutting. Some sparks might even fly out from the top.

If they’re flying out of the top, it means your plasma arc isn’t cutting all the way through, and the sparks are bouncing off the part that is still joined together.

If they are coming out straight down, but you’re getting stuck in grooves, you’re cutting too slow. Cutting too slow results in a wider kerf (the material lost due to the cutting process) and dross (excess metal from the cut that hardens on the bottom of the piece and needs to be cleaned off). Cutting too slow also makes the cut much harsher; it won’t be as smooth as it could be.

Cutting Your Metal

Before you cut, make sure to mark out where you want to cut, whether it’s a straight line or a shape; freehand cutting will always be worse than a guided cut.

To do the actual cut is relatively easy. Once your machine and torch are all ready to go, place the tip of your torch flush with the metal where you’re cutting, pull the trigger and away you go.

For extra accuracy on your cuts, add a piece of sheet metal to push the torch up against to keep your lines straight (if you want straight lines). You can also measure from the shield’s outer edge to the centre of the cutting tip opening and add that width between the line you wish to cut and the sheet metal you’re leaning against. This will mean that your cut will be dead on, rather than slightly to the side of where you drew it. You can get circle cutting attachment kits for some plasma torches to help you make perfect circles.

If you are starting in the middle of a plate and piercing straight through, it’s a good idea to angle the cutter at roughly a 45° angle so that the metal doesn’t jump back at the shield and clog it up.

Once you’ve pulled the trigger and the plasma has pierced all the way through the metal, you can angle back up to 90° and begin cutting. If you’re just starting from an outer edge, you can just start at 90°.

If you’re gouging instead of cutting, the process is almost the same. You’ll still run your torch along in a line, but rather than hold it straight up and down, keep it at a roughly 45° angle from the metal (as if you’re pushing a MIG torch), as this helps avoid going through the piece.

Even if you have the right travel speed, which corresponds with the amps and air pressure, plasma cutting will leave a bit of dross (leftover metal) on the bottom. This can be removed with a chipping hammer; it’s generally not too thick, so it’s easy to clean up.

CNC Tables

CNC stands for Computer Numerical Control and what that means is a computer does all the hard work for you.

A CNC table, therefore, is a table that comes with a computer that does the cutting for you. These tables come with all the equipment needed (an X-axis and a Y-axis) that you can mount a router (the torch) to.

These tables are usually used in auto repair, machine fabrication and construction (to name a few) to make precision cuts that are impossible to get with a hand-held tool.

You do need to program what you want into a CNC computer, and there are specific programs (one that interprets M-codes & G-codes) that need to be used for the computer to understand what kind of cuts you’re inputting. Some of the software you can use include AutoDesk Fusion 360 CAD/CAM Software.

These CNC tables usually work by connecting the plasma torch to an arm that can run back and forth (Y-axis) and left to right (X-axis) over the table.

A specific CNC plasma torch attaches to this arm and makes the cuts that have been programmed in. This torch is pretty similar to a hand-held torch and also comes with changeable consumables for contact or stand off cutting. Instead of a handle with a trigger, the main difference is that it has a long, straight plastic tube that the consumables attach to.

These CNC plasma cutting torches are available at UNIMIG, and some UNIMIG machines come with a CNC connection, so you can hook them up to any model of plasma cutting table.

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There are a few factors that you should consider before diving into buying a machine. These include the material, the material thickness, the weld type (MIG, TIG or stick), the power, and, most importantly, your budget.

The material you want to weld, and its thickness, will determine the welding process that will work best for you, especially as not every welder can do every material.

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• MIG Welders
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What material are you going to be welding?

How thick is the material you plan to weld?

The output of your welder will determine the material thickness you will be able to weld.

These sizes are subject to the power your welder can output, so always check the product specifications.

What’s the difference between MIG, TIG & Stick?

If you want a more in-depth look at the differences between these welding types, you can check out our MIG vs TIG vs STICK blog.

Now you should have a decent idea of which type of welding you think will work best for your needs; we can start narrowing the options even more.

What power points are available to you?

The power you can plug into is going to dictate the range of machines you can pick from. Every machine needs to be connected to a power source (otherwise, there’s no electric circuit).

If you’re planning on welding in your spare time on weekends at home, it’s likely you’ve only got standard 10A domestic outlets available to you. If that’s the case, you’re only going to be able to get a machine that has a 10A plug.

Another thing to keep in mind is that a 10A plug will usually support up to 180 amps, and a 15A plug will usually support up to 200 amps. Anything over that (like the 250+ amp machines) will require an authorised electrician to install a plug (20A or 32A) for you by Australian law.

How long do you want to weld for?

There’s one main thing on a welder that will determine how long you’re going to be able to use it without stopping—the duty cycle. A welder’s duty cycle should always be included in the product’s specifications, as this is an essential feature on every machine.

If you were to look at the Viper 185 MIG/TIG/STICK welder’s duty cycle, it would look like this: 10% @ 180A. It doesn’t look like much, but what this means is that you can use the welder on its max amperage (180A) for a full minute straight before it overheats.

The duty cycle is measured in 10-minute increments, so if you have a 10% duty cycle at max amps, you’ll have 1 minute of constant welding and then 9 minutes of cooldown time.

Now, you’re probably thinking, ‘One minute? That sounds terrible!’ Three things make this an excellent duty cycle. The first and most impressive is that every UNIMIG machine is tested at an outside temperature of 40° Celsius.

The welder will run for a full minute on max amps in 40°C before it overheats and the thermal overload kicks in. It also means that if you’re welding in a room that’s only 20°C, your welder’s going to last longer than what’s stated on the technical sheet.

Not every manufacturer discloses the temperatures that they test their machines at, so you run the risk of getting a duty cycle that might be slightly exaggerated, especially if they’re testing them in their own controlled environments.

The second reason that a 10% duty cycle isn’t as bad as you think is that one minute is a really long time. A straight one minute of welding is usually a long weld joint, and you’ll likely have finished the weld or pulled away to reposition before the minute is up.

The third reason is that most welders don’t need to be set to their max amperage (in some cases, it’ll blast through your weld). If you’re welding on or with thinner materials, your machine is probably going to be set in a mid-range amperage, so the welder will last for longer on lower amps.

VIPER vs RAZOR

VIPER machines are designed for home DIY projects and weekend hobbyists, but they’re also great for any offsite work. The VIPER machines are lightweight, portable, and with a 10A plug, they’ll go just about anywhere.

They’re built to be user-friendly, making setting up and getting started as quick and easy as possible. The VIPER machines come with helpful setup guides on their inside panel so that no matter what level welder you are, you can get the machine running without issues.

On the other hand, RAZOR machines are made to suit a range of professional and industrial needs. They’re usually equipped with a 15A plug, but some of the really high amperage machines require specialised plug sockets. The bigger plugs mean that most of the RAZOR range can do a much higher max amp output than the VIPERs.

Our RAZOR machines also come with a full 3-year or 5-year warranty, compared to the 1- to 3-year warranties available on the VIPERs.

If you get a VIPER or a RAZOR, you can get an extra six-month warranty if you register your machine online.

What kind of budget do you have?

Your budget is going to be a crucial factor when it comes to picking a welding machine. Only you know how much you have to spend, but what you do need to keep in mind is that it isn’t just the machine you’re going to need.

Regardless of whether you’ve decided to MIG, TIG or stick weld, you’re going to need a few extras:

• Filler metals
• Consumables (these need to match your wire sizes which in turn need to match your material size)
• Gas tanks (if needed)

You could buy a TIG machine and decide later on that the torch it came with is getting too hot too fast, and you want to try a water-cooled one instead.

Getting a cheap welder can be tempting, but if you save in cost, you’re going to sacrifice so much for it. The performance might not be as good, the parts will probably wear out faster, and if it needs servicing or troubleshooting, you could be out of luck.

UNIMIG machines have decades of professional tried and tested technologies under their belts. You’ll be buying from a top-tier, Aussie-owned family business with local support centres across the country. Just something to think about before you go for that import brand welder that’s only going to save you upfront, but there’s a chance you’ll pay for it in the future.

Synergic Control

Generally speaking, synergic means combining several systems to make one. When it comes to welding, this means that the machine is pre-programmed with a set of parameters that allow it to select the best settings for you automatically.

The programs for UNIMIG’s synergic controlled machines were made in collaboration with an expert welder to ensure that their parameters are going to produce a good weld. There’s no guesswork involved, and you’ve usually only got one knob to play around with.

Depending on the machine, you’ll need to input the material type, filler type, filler size, gas type and the parent metal thickness. Once you’ve input these, it will automatically decide your welding parameters for you, and you can start welding straight away.

Synergic welders are an excellent choice for beginners and professionals alike, as you won’t need to spend any time messing with the settings to get the weld right. Some of these machines will come with the option to switch to a manual mode, so you can input your own preferred settings instead.

Even if you are using a synergic machine, for the most part, these will let you alter the chosen settings for minor adjustments. The synergically chosen settings might be slightly off for your particular job, so instead of having to set everything manually to get it right, you can still adjust your voltage, wire feed speed or amperage to suit.

MIG Welders

VIPER MULTI 135 Welder

• 3-in-1 multi-process machine
• One knob synergic MIG control
• Gas & gasless
• 10A plug

This machine is perfect for first-time welders as the single-knob synergic MIG control means you don’t need to play around with a bunch of settings. Select your wire size and material thickness, and the machine will do the rest.

As well as synergic MIG for easy setup, it’s also a 3-in-1 machine, so you can TIG and stick weld with it as well. As a new welder, you can try out all three of the standard welding processes or use it as a super portable professional machine that’ll plug in anywhere. Its 100mm wire spool holder means that it’s super lightweight and portable.

It comes with a MIG direct connect torch, and it only does Lift Arc DC TIG, so it can’t weld aluminium.

View more info: VIPER MULTI 135

VIPER MULTI 165 Welder

• 3-in-1 multi-process machine
• Synergic MIG control
• Gas & gasless
• 10A plug

The VIPER MULTI 165 is a great all-rounder machine that entry-level welders can learn all forms of welding with. As a 3-in-1 machine, it can MIG, Lift Arc DC TIG and can stick weld, and with the Euro connect MIG torch, you can MIG weld aluminium as well.

It comes with synergic MIG programs, so setting up for your weld is quick and easy; just select your wire size and type. The internal spool holder can hold both 100mm and 200mm spools.

As well as being beginner friendly, with 165 amps of power and a 10A plug, it can also be used as a portable professional machine that you can take anywhere.

View more info: VIPER MULTI 165

VIPER 185 MIG/TIG/STICK Welder

• 3-in-1 multi-process machine
• Gas & gasless
• Geared wire drive
• Spool gun ready
• 10A plug

The VIPER 185 is designed for use by home hobbyists and DIY welders. A 3-in-1 welding machine capable of MIG, Lift Arc DC TIG, and stick welding that puts out over 180 amps that won’t break the bank.

The VIPER 185 comes with a geared wire drive, so you get better and smoother wire feeding. It’s also spool gun compatible, so you can run softer wires, like aluminium, with ease. You don’t even need to remove your existing torch setup, so you won’t waste any wire when swapping wires. Plus, with a Euro connect MIG torch, you can run aluminium wires through the standard torch or the spool gun.  

Lightweight and portable, with a 10A plug, you can take this machine anywhere, and with the high output power, this machine is perfect for professional work as well.

View more info: VIPER 185

VIPER MULTI 195 MAX Welder

• 3-in-1 multi-process machine
• Synergic MIG and TIG control
• 4” LCD screen
• Gas & gasless
• Digital geared wire drive
• Spool gun ready
• Dual gas input
• Job memory
• Power Factor Correction (PFC)
• 10A plug

The VIPER MULTI 195 MAX is our most advanced beginner machine. A 3-in-1 machine that can MIG, high-frequency DC TIG, and stick weld, it can do almost everything. The 4” LCD screen is bright and clear and makes navigating through the settings easy. 

It comes preloaded with over 100+ MIG and TIG synergic programs. Select your metal, wire size and type, and gas, and the machine will do the rest. You can be set up in seconds whether you’re MIG or TIG welding. On top of the synergic programs, it also has a complete MIG weld cycle, including pre- and post-gas flow, arc ignition speed and burnback.

It’s spool gun compatible, so you can run aluminium wire through the standard torch or a spool gun; the choice is yours.

The digital drive roller system instantly adapts to varying welding conditions to maintain a consistent arc and wire feed speed, so you get unparalleled accuracy under any circumstances.

The high-frequency TIG means starting a weld is effortless, and you get a complete weld cycle with pre- and post-gas flow and up and down slope parameters. The high-frequency ignition also means you can connect a foot pedal to this machine.

Complete with PFC; this machine comes equipped with a few extra internal components that keep the current from fluctuating and have it running at its optimal power.

View more info: VIPER MULTI 195 MAX

RAZOR MULTI 175 Welder

• 3-in-1 multi-process machine
• HD backlit interface
• Synergic MIG control
• Gas & gasless
• Geared wire drive
• Spool gun ready
• 15A plug

RAZOR MULTI 220 Welder

• 3-in-1 multi-process machine
• HD backlit interface
• Synergic MIG control
• Gas & gasless
• Geared wire drive
• Spool gun ready
• 15A plug

RAZOR MULTI 250 Welder

• 3-in-1 multi-process machine
• HD backlit interface
• Synergic MIG control
• Gas & gasless
• 4 geared wire drive
• Spool gun ready
• 15A plug

A step up from the VIPER range, the RAZOR machines are designed for professional and industrial use.

All three of these machines are 3-in-1 multi-process welders, complete with MIG synergic programs across mild steel, stainless steel and aluminium for easy setup. The large, clear HD backlit interface makes reading and adjusting your settings a breeze.

The geared wire drives in these machines provide better and smoother wire feeding, especially the 4-geared drive, as it comes with an extra set of rollers. These machines are also spool gun compatible, so you can run softer wires, like aluminium, with ease. You don’t even need to remove your existing torch setup.

If you’re a home hobbyist, don’t feel like you’re limited to the VIPER machines. If you’ve got a project in mind that requires some more amps than they can provide, the only thing stopping you from getting a RAZOR is your plug sockets. If you don’t have a 15A socket, don’t stress, you can just get one installed in your garage or workspace, and you’re set.

View more info: RAZOR MULTI 175, RAZOR MULTI 220 & RAZOR MULTI 250

RAZOR MULTI 230 AC/DC Welder

• 4-in-1 true multi-process machine
• Synergic MIG and TIG control
• Dual 10A & 15A plug
• 5” LCD screen
• Gas & gasless
• Advanced MIG settings
• Geared wire drive
• Spool gun ready
• Multiple AC waveforms
• Mixed arc AC/DC
• Pulse MMA
• Dual gas input
• Job memory
• Power Factor Correction (PFC)

The RAZOR MULTI 230 AC/DC is one of our most advanced professional machines. It’s a 4-in-1 machine which means it can do every kind of welding there is. MIG, MMA, DC TIG, and, finally, AC TIG. That means you can now TIG weld aluminium on a MIG machine, making it a true all-process machine. 

Plus, the machine does high-frequency TIG, whether you’re in AC or DC. That means you have more control when starting or stopping the arc, and reduce the risk of contaminating the tungsten or the weld, so you’ll have no issues when it comes to aluminium. 

You get complete control over your TIG welds. Both the AC & DC TIG welding modes come with the full weld cycle. You can adjust all the parameters, like pre- and post-flow, up and down slopes, as well as all things pulse. 

It also has a complete MIG weld cycle, including pre- and post-gas flow, arc ignition speed and burnback. Plus, it comes with advanced MIG features, including hot or cold arc starts, crater fill and inductance controls.  

The 5” LCD screen is bright and clear and makes scrolling through your parameters a breeze. It comes preloaded with over 100+ MIG and TIG synergic programs, so setting up for your weld has never been easier. Select your metal, wire size and type, and gas, and the machine will do the rest. You can be set up in seconds whether you’re MIG or TIG welding.

The MULTI 230 AC/DC comes packed with advanced TIG features like multiple AC waveforms, mixed arc AC/DC and all-new ‘Plus’ programs. Adjust the characteristics of your AC arc, have your weld switch between AC and DC- currents as you go with the mixed arc AC/DC (giving you the best of both worlds in a single weld), or totally customise your TIG weld with the ‘Plus’ programs.

The dual 10A and 15A plug on this machine means you won’t be limited to where and when you can use it. Whether you’re working on something in your garage or taking it to job sites, you can plug in anywhere with the supplied adapter plug. It also comes with dual gas inputs, so you can have a TIG and MIG gas bottle connected at the same time.

The job memory feature lets you save specific settings so you won’t have to re-enter the same thing over and over. It’s spool gun compatible, so you can run aluminium wire through the standard torch or a spool gun. The geared wire drive gives you smooth and consistent wire feeding across every wire.

Complete with PFC; this machine comes equipped with a few extra internal components that keep the current from fluctuating and have it running at its optimal power.

View more info: RAZOR MULTI 230 AC/DC

RAZOR 200 PULSE Welder

• Single & double pulse MIG
• Synergic MIG control
• 3-in-1 multi-process machine
• 5” LCD touchscreen
• Advanced MIG settings
• Gas & gasless
• 4 geared wire drive
• Digital MIG torch
• Spool gun ready
• Job memory
• 15A plug

The RAZOR 200 PULSE, our most advanced machine, is a 3-in-1 that can MIG, high-frequency DC TIG, and stick weld, so it can do almost everything. The large 5” LCD touchscreen is bright and clear and makes navigating through the machine settings a breeze. 

As well as standard MIG, it can also do single and double MIG welding. Pulse welding reduces the heat and minimises spatter without compromising penetration, so it’s perfect for thin and soft materials like aluminium.

A single pulse weld alternates between a peak current and a background current. Double pulse welding works the same way but with a second background current to add even more control over the arc.

There are plenty of benefits to pulse MIG welding, including a reduced heat input, faster weld speed than TIG but with the same aesthetic appearance, spatter-free welding for minimal cleanup, and great penetration (even with lower heat).

This machine comes with over 100+ synergic MIG programs that cover the standard, single and double pulse MIG processes, so regardless of the MIG welding you want to do, you can be up and running in seconds.

As well as its pulse and synergic programs, it also comes packed with other advanced MIG features like hot start, crater fill and inductance, so you can completely customise your welds. Plus, get smooth and consistent wire feeding with the 4 geared wire drive system.

The digital MIG torch that comes provided with the machine lets you adjust your welding parameters right on the handpiece itself, so you don’t have to go back and forth to the machine to make changes. You can also save your top 100 favourite or most common weld settings with the job memory menu.

View more info: RAZOR 200 PULSE

RAZOR COMPACT 250 Welder

• 3-in-1 multi-process machine
• HD backlit interface
• Synergic MIG controls
• Gas & gasless
• 4 geared wire drive
• Digital MIG torch
• Spool gun ready
• Push-Pull gun ready
• 300mm wire spool capacity
• Power Factor Correction (PFC)
• 15A plug

A 3-in-1 welding machine capable of MIG, Lift Arc DC TIG, and stick welding, the RAZOR COMPACT 250 has complete MIG synergic programs across mild steel, stainless steel and aluminium for easy setup. The large, clear HD backlit interface makes navigating the settings easy.

The 4 geared wire drive provides better and smoother wire feeding, and the digital MIG torch that comes provided means you can adjust your parameters right on the handpiece.

Though it’s called ‘compact’, the reality is the RAZOR COMPACT 250 is bigger than the standard RAZOR MULTI machines. There’s a good reason for this: it comes with a built-in trolley – it’s on wheels.

The bigger cabinet also means it has the added benefit of being able to hold a much larger wire spool. You’re not limited to 5kg spools, which makes this an ideal machine for professionals and workshops.

This machine is both spool gun and push-pull gun compatible, so you can choose how you want to run your softer wires like aluminium. The second drive motor in the push-pull torch makes it ideal for welding over long distances with its 8m lead.

Equipped with PFC, this machine has a few extra internal components that keep the current from fluctuating and have it running at its optimal power. The addition of PFC means this machine can be run at its full output on just a 15A plug.

View more info: RAZOR COMPACT 250

RAZOR 350 COMPACT MIG/TIG/STICK Welder

• 3-in-1 multi process
• Gas & gasless
• 4 geared wire drive
• Spool gun ready
• Push-Pull gun ready
• 300mm wire spool capacity
• Three-phase/415V power

The RAZOR 350 COMPACT is a 3-in-1 welding machine capable of MIG, Lift Arc DC TIG, and stick welding.

As a COMPACT machine, it comes with a built-in trolley, and the bigger cabinet means it has the added benefit of being able to hold a much larger wire spool. You’re not limited to 5kg spools, which makes this an ideal machine for professionals and workshops.

This machine is both spool gun and push-pull gun compatible, so you can choose how you want to run your softer wires like aluminium. The second drive motor in the push-pull torch makes it ideal for welding over long distances with its 8m lead.

We recommend that the 350 COMPACT be used by professional welders in construction or workshop environments because it’s a three-phase machine and will need a 32A plug installed by a licensed electrician.

View more info: RAZOR 350 COMPACT

RAZOR 350 SWF MIG/TIG/STICK Welder

• 3-in-1 multi process
• Separate wire feeder
• Gas & gasless
• 4 geared wire drive
• Spool gun ready
• Push-Pull gun ready
• Three-phase/415V power

RAZOR 500 SWF MIG/TIG/STICK Welder

• 3-in-1 multi process
• Separate wire feeder
• Gas & gasless
• 4 geared wire drive
• Spool gun ready
• Push-Pull gun ready
• Three-phase/415V power

These two RAZOR machines are the same; the only difference is their max amperage, which affects how thick the material you want to weld on can be. They come with a little box that sits on top called a traveller, which can be removed from the main unit.

These machines are pretty big, and they’re designed for industrial and construction work that requires welds on thicker metals. The traveller can be moved 10 metres away from the unit and has its own wire feeder inside it, so even if you can’t move the entire welder, you can take the box with you into hard-to-reach spaces.

They’re both 3-in-1 welding machines, capable of MIG, Lift Arc DC TIG and stick welding. Plus, the 4 geared wire drive provides better and smoother wire feeding.

These machines are spool gun and push-pull gun compatible, so you can choose how you want to run your softer wires like aluminium. The second drive motor in the push-pull torch makes it ideal for welding over long distances with its 8m lead.

We recommend that these machines are used by professional welders in construction or workshop environments because they’re three-phase machines and will need a 32A plug installed by a licensed electrician.

View more info: RAZOR 350 SWF & RAZOR 500 SWF

Every one of our MIG welders comes with a Twist Lock Electrode Holder to stick weld with.

TIG Welders

VIPER 180 AC/DC Mk II TIG/Stick Welder

• AC/DC high-frequency TIG
• Pulse TIG function
• Foot control ready
• 2T/4T/SPOT torch modes
• 10A plug

This VIPER TIG welder is great for the handyman, especially if you’re still getting the hang of the TIG welding technique. It allows for both AC and DC currents, so you can use it for aluminium as well as mild and stainless steels.

The complete weld cycle means you have full control over your weld, from pre-gas to post-gas. It also includes pulse functions in both DC and AC, so you can pulse weld anything, and the range of torch modes lets you weld the way you find most comfortable.

With the high-frequency start, you can ignite your arc with just the click of a button, and you can switch to a foot pedal and try that out. It comes with the T2 TIG torch to give you consumables with a longer life and a lighter torch.

This updated Mk II version of the VIPER 180 is both smaller and lighter than its predecessor but just as powerful.

View more info: VIPER 180 AC/DC Mk II

RAZOR TIG 200 AC/DC Welder

• HD backlit interface
• AC/DC high-frequency TIG
• Pulse TIG function
• Multiple AC waveforms
• Mixed arc AC/DC
• Foot control ready
• 2T/4T/S4T/SPOT torch modes
• Advanced MMA features
• Power Factor Correction (PFC)
• 10A plug

A step up from the VIPER range, the RAZOR machines are designed for professional and industrial use. This high-frequency AC/DC TIG welder gives you control of the full weld cycle, regardless of what you’re welding. The large, clear HD backlit interface makes reading and adjusting your settings a breeze.

Adjust the characteristics of your AC arc with the different AC waveforms available, or have your weld switch between AC and DC- currents as you go with the mixed arc AC/DC feature, which gives you the best of both worlds in a single weld.

It also includes pulse functions in both DC and AC, so you can pulse weld anything, and the range of torch modes lets you weld the way you find most comfortable.

With the high-frequency start, you can ignite your arc with just the click of a button, and you can switch to a foot pedal and adjust your amperage while you weld. It comes with the T2 TIG torch to give you consumables with a longer life and a lighter torch.

On top of being a TIG welder, you also have to option to stick weld, with several advanced features packed in, like hot start, arc force and built-in anti-stick.

Equipped with PFC, this machine has a few extra internal components that keep the current from fluctuating and have it running at its optimal power.

The addition of PFC means this machine can be run at its full output on just a 10A plug. You can take this professional-grade welder with you anywhere that has a standard domestic outlet.

View more info: RAZOR TIG 200 AC/DC

RAZOR TIG 220 DC Welder

• HD backlit interface
• DC high-frequency TIG
• Pulse TIG function
• Foot control ready
• 2T/4T/S4T/SPOT torch modes
• Advanced MMA features
• Power Factor Correction (PFC)
• 10A plug

The RAZOR TIG 220 DC is a DC-only machine. You won’t be able to use it to weld aluminium, which will only work on an AC. This high-frequency DC TIG welder gives you control of the complete DC weld cycle, including pulse TIG parameters.

The large, clear HD backlit interface makes reading and adjusting your settings a breeze. The range of torch modes lets you weld the way you find most comfortable.

With the high-frequency start, you can ignite your arc with just the click of a button, and you can switch to a foot pedal and adjust your amperage while you weld. It comes with the T2 TIG torch to give you consumables with a longer life and a lighter torch.

On top of being a TIG welder, you also have to option to stick weld, with several advanced features packed in, like hot start, arc force and built-in anti-stick.

Equipped with PFC, this machine has a few extra internal components that keep the current from fluctuating and have it running at its optimal power.

The addition of PFC means this machine can be run at its full output on just a 10A plug. You can take this professional-grade welder with you anywhere that has a standard domestic outlet.

If you weren’t planning on welding aluminium, then save yourself some money and grab a DC-only machine.

View more info: RAZOR TIG 220 DC

RAZOR 320 AC/DC TIG Welder

• AC/DC high-frequency TIG
• Pulse TIG function
• AC TIG waveforms (square, trapezoidal and sine)
• Mixed arc AC/DC
• Job memory
• Water cooler available
• Foot control ready
• 2T/4T torch modes
• Three-phase/415V power

This high-frequency AC/DC TIG welder allows for both AC and DC currents, so you can use it for aluminium as well as mild and stainless steels and customise the entire weld cycle.

The complete weld cycle means you have full control over your weld, from pre-gas to post-gas. It also includes pulse functions in both DC and AC, so you can pulse weld anything, and the torch modes let you weld the way you find most comfortable.

With the high-frequency start, you can ignite your arc with just the click of a button, and you can switch to a foot pedal and adjust your amperage while you weld. It comes with the T3 TIG torch to give you consumables with a longer life and a lighter torch.

The different AC waveforms let you adjust the characteristics of your AC, letting you weld aluminium the way you want to. The mixed arc AC/DC means that you can have a weld that switches between AC and DC- currents as you go, giving you the best of both worlds in a single weld.

The job memory feature means that you can save specific settings in it the same way you set the radio stations in your car. You won’t have to re-enter the same thing over and over.

This welder has an optional water cooler, as well as its own specially designed trolley that houses the water cooler. Unlike other water coolers, it only turns on while you’re welding, so there’s no loud background noise. The trolley and water cooler are sold separately.

The 320 AC/DC is a three-phase machine and will need a 20A plug installed by a licensed electrician.

View more info: RAZOR 320 AC/DC

Every one of our TIG welders comes with a Twist Lock Electrode Holder to stick weld with.

Stick (MMA) Welders

VIPER ARC 140 STICK Welder

• DC scratch start TIG
• 10A plug

The VIPER ARC 140 is a super simple, super easy-to-use stick welder that you can use at home. This machine is almost totally stick-dedicated, and although you can attach a TIG torch to it, you’ll only be able to use the scratch start TIG process.

This machine is the most affordable unit in our range, so it’s a great place to start if you’re just starting out with stick welding.

View more info: VIPER ARC 140

RAZOR ARC 140 Welder

• HD backlit interface
• DC Lift Arc TIG
• Advanced MMA features
• 10A plug

RAZOR ARC 180 Welder

• HD backlit interface
• DC Lift Arc TIG
• Advanced MMA features
• 15A plug

These RAZOR stick machines are majority stick orientated; however, they do come with the option to swap to DC TIG mode. This switch means that you’ll be able to use the lift arc ignition instead of scratch start, which minimises the risk of tungsten contamination.

They’re easy to use with the one adjustable knob to choose your amps, and the large, clear HD interface makes them easy to read. 

These machines include advanced features like built-in Anti-Stick technology, as well as adjustable Hot Start and Arc Force functionality which are designed to improve weld quality and ease of use.

The Hot Start feature increases the stability of your arc ignition and prevents a lack of fusion at the start of the weld. You won’t ever struggle to strike an arc again.

The Arc Force feature helps to keep the arc stabilised throughout the weld, by detecting any short circuits and increasing the peak current to prevent the arc from cutting out or the electrode from sticking.

The Anti Stick feature, which is always on, prevents your electrode from sticking to your workpiece. When the machine detects sticking, the current will shut off and unstick the electrode.

View more info: RAZOR ARC 140 & RAZOR ARC 180

RAZOR ARC 160 PFC Welder

• HD backlit interface
• Advanced MMA features
• DC Lift Arc TIG
• Power Factor Correction (PFC)
• 10A plug

RAZOR ARC 200 PFC Welder

• HD backlit interface
• Advanced MMA features
• DC Lift Arc TIG
• Power Factor Correction (PFC)
• 15A plug

These professional-grade RAZOR stick welders are the next step up. They’re still one knob control for ease of use, and the large, clear HD backlit interface is just as easy to read and navigate.

These machines include advanced features like built-in Anti-Stick technology, as well as adjustable Hot Start and Arc Force functionality which are designed to improve weld quality and ease of use.

The Hot Start feature increases the stability of your arc ignition and prevents a lack of fusion at the start of the weld. You won’t ever struggle to strike an arc again.

The Arc Force feature helps to keep the arc stabilised throughout the weld, by detecting any short circuits and increasing the peak current to prevent the arc from cutting out or the electrode from sticking.

The Anti Stick feature, which is always on, prevents your electrode from sticking to your workpiece. When the machine detects sticking, the current will shut off and unstick the electrode.

Plug in a TIG torch and switch to DC TIG mode on the machine to lift arc TIG with this machine.

These welders also have the bonus feature of PFC. This means the machines are equipped with internal components that keep the current from fluctuating and have it running at its optimal power.

View more info: RAZOR ARC 160 PFC & RAZOR ARC 200 PFC

Every one of our stick machines comes with VRD built in to ensure the safety of the welder at all times.

No matter the kind of welding you’ve got planned, we’ve got a machine that can handle the job.

Still not entirely sure what you’re looking for? Browse the full range of welders.

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The post How to Choose the Right Welding Machine for You appeared first on UNIMIG.

Stick welding is a good middle ground and is perfect for those who don’t want the hassle of a gas tank or want to weld thicker pieces of metal.

Quick Navigation

Jump to:

• Electrodes
• Settings
• Weld Preparation
• Making the Weld

What is Stick Welding?

Manual Metal Arc (MMA) or ‘Stick’ welding is the process in which a power source is used to create an electric arc between a flux covered electrode and the workpiece. Strike the electrode against the metal to ignite it and then melt the electrode into the joint to create the weld.

The flux covering acts as a protective layer for your weld, so there is no protective gas needed for this process. This protective coating on the electrode leaves behind a topcoat on your weld known as ‘slag’, which needs to be removed to achieve a clean weld.

Machine Setup

1. Stick Electrodes
2. Electrode Holder
3. Polarity
4. Settings

Almost all UNIMIG machines are suitable for stick welding, as the torch attaches into the panel mount, which both MIG and TIG machines are equipped with. There are a few dedicated stick welders, and the setup of these is very straightforward.

1. Stick Electrodes

Stick welding electrodes come in a range of classifications and sizes for every kind of weld. The first thing you need to do is match your electrode to your parent metal, and then you need to pick a size that’s relevant for the thickness you want to weld.

Each electrode has the classification stamped on the end, which goes into the electrode holder. Carbon steel electrodes are stamped with a 4-digit code. For example: E6013

• The “E” indicates electrode
• The first 2 digits refer to the tensile strength (how much weight it can withstand after welding) of the electrode
• The 3rd digit indicates the position (see below) that the electrode can be used in
• The 4th digit indicates the flux coating and the current to be used

The “E” remains constant on every type of electrode because they’re all electrodes.

The first two numbers do not vary much as the weld needs to be stronger than the metal welded, so most electrodes have a tensile strength of 60,000ksi or 70,000ksi, which covers pretty much everything.

There are only three variations of the third number: 1 (all positions), 2 (flat & horizontal) and 3 (flat only). Most electrodes are coded with ‘1’ as they can do every position.

The fourth number is the type of flux coating on the electrode. This is the most varying part of every electrode, as there are 9 types of coating, the flux coating will determine how the weld puddle reacts.

The most common stick electrode classifications are E6010, E6011, E6013, E7016, E7018 & E7024. Out of these, if you’re just starting your welding journey, the best choice for carbon steel would be:

• E6013: this electrode is general purpose; it can be used on most applications from furniture to fencing, all positional, with easy striking and slag removal.
• E7016/E7018: these are low hydrogen, sometimes referred to as hydrogen controlled. They’re all positional (except vertical down), the 16 is ideal for a high-quality weld, and the 18 contains iron powder as well, giving it a higher deposit rate (a fatter weld).

On top of your standard carbon steel electrodes, you can also get hard facing and cast-iron sticks.

• Hard Facing: these are used for things that cop some severe abuse, like the teeth on earth moving equipment. Having a harder metal means it won’t wear out as fast. One of the more common hard facing electrodes is the 531. The difference between these classifications is the hardness you require.
• Cast Iron: cast-iron is made as one solid piece by pouring molten iron mixtures into moulds. Cast iron rods are used to weld pieces back together once they break as they’re made up of the right chemical compound. Some common classifications on these are Ni 98 (or 402Ni) and Ni 55 (or 416NiFe).

If you’re looking for stainless steel electrodes, these are stamped with the metal’s grade; 308L, 309L, 312L & 316L are the most common.

You can get dissimilar metal electrodes (stainless 309L & 312L are some examples); these are designed for welding together stainless steel and carbon steel or steels of unknown nature.

Single vs Twin Coat

Most stick electrodes are single coated, which means that all the ingredients needed to make it both conductive and protective are included in the same outer layer that coats the inner core. However, you can purchase twin coated electrodes. What is a twin coated electrode though? It’s exactly what it sounds like: it has two layers.

The inner layer contains the ingredients that ionise and make it conductive, which provides a stable, concentrated arc around the wire. The second layer contains the shielding and slag forming components. It is non-conductive, which also helps to concentrate the arc and make it easier to direct.

There are quite a few benefits with a twin coated electrode, and they’re generally more popular with the operators, but only E7016s are available with twin coating.

UNIMIG sells a range of general purpose, low hydrogen, stainless steel, hard facing and cast-iron electrodes, including our HYPERARC 16TC Low Hydrogen Electrode.

If you’re looking to weld aluminium, don’t even bother with stick welding. Instead, check out our guides on MIG and TIG welding, as they’re much better welding options for an aluminium project.

2. Electrode Holder

There are two types of torch that you can purchase to place your electrode in for the weld: the square/twist lock holder and tongs.

Electrode Holder vs Tongs

The most significant difference between these two ‘torches’ is how they look. The twist lock holder has a square opening which clamps your electrode into place once the head is twisted clockwise.

The tongs look exactly like tongs, with grooves along the insides for the angle you want your electrode. (If none of the groove positions fit the angle you’re looking for, you can just bend the electrode where it attaches for the perfect angle.)

The reality is these two types of electrode holders do the same thing: clamp your electrode in place. In America, the tongs are the most popular, and in Australia, the twist lock holder is more popular. That’s why most of the stick welders by UNIMIG come with a twist lock electrode holder when you purchase them.

3. Polarity

Stick welding can be done in both positive and negative polarities, but unfortunately, there is no hard and fast rule on setting the torch up. The required polarity is listed on the front of the box of electrodes, so make sure to keep the front label and read it so you can set your machine up correctly.

• If the electrodes ask for an AC/DC+, you’ll need to attach your earth clamp into the Negative (–) panel mount and the torch into the Positive (+) panel mount.
• If the electrodes ask for an AC/DC–, you’ll need to attach your torch into the Negative (–) panel mount and the earth clamp into the Positive (+) panel mount.

When working in DC, some electrodes might ask for a DCEP (Direct Current Electrode Positive) or a DCEN (Direct Current Electrode Negative). The last letter is the most important and refers to the polarity required. Most electrodes will need a positive polarity.

4. Settings & Amperage

The settings on a machine made specifically for stick welding are the easiest to figure out. All you have to do is pick your amps, and you’re ready to go. However, if you’re using a MIG or TIG machine, you’ll need to select ‘MMA/stick’ mode on the machine. The control may be a scroll through option or a switch on the front of the machine, depending on what you have.

For example, if you’re using the VIPER 185 MIG/TIG/Stick Welder machine, there’s a switch on the right-hand side labelled MMA/TIG/MIG. You would need to place it into the MMA mode and then use the far-left knob (labelled ‘A’ and with an image of a stick gun) to adjust the amps for your electrode.

The number of amps you need will depend on how thick your electrode is (and, therefore, how thick your parent metal is). UNIMIG has a useful starting guide with amperage ranges for a few types of electrodes and their thicknesses, which can be found in our free e-book The Ultimate Welding Guide.

For example, if the metal you’re looking to weld is a 4mm mild steel downhand butt weld, you’ll need a 2.6mm HYPERARC General Purpose 6013 electrode, and you’d set your amps somewhere between 60-65. If you’re unsure of where in that range to start, try the middle first and adjust if need be.

While welding, there are a few indications that your amperage is set incorrectly. If your amps are too high, the arc will be fierce, with too much penetration and spatter spraying everywhere. If your amps are too low, you’ll have a very soft arc, there’ll be barely any fusion between the metals, and your electrode will likely stick more.

Keyable VRD

VRD stands for Voltage Reduction Device. The keyable switch means that this setting can be turned on or off to suit your application. You may also be required to have it turned on by your site foreman, and a keyable switch allows this while also letting you turn it off if you’ve got difficult to start electrodes.

Metal Preparation

Unlike MIG and TIG welding, there is no need to prepare your metal. Because of the flux coating on each electrode, stick welds are tough enough to go over rust and other things that would usually cause contamination without any problems.

Storage

Some electrodes need to stay dry to keep the weld moisture and contaminant free. To achieve this, some manufacturers vacuum-seal their electrodes so that they’ll remain moisture-free until they reach the customer. UNIMIG’s HYPERARC 16TC Electrodes come in a vacuum-sealed package, so they’ll be ready for use as soon as you open the packet.

If you don’t have somewhere dry and sealed to store these, or they become filled with a bit of moisture, you can re-bake the electrodes in an electrode oven to dry them out.

The only electrodes that you do need to worry about re-baking are the low hydrogen ones (E7016 & E7018), as they must remain moisture-free. It doesn’t matter too much if the others aren’t baked, as it won’t affect the weld.

Please do not try to bake your electrodes in a kitchen oven. It doesn’t work. Your oven can’t get enough concentrated heated into the electrode, so all you’ll be doing is wasting your time and potentially covering your electrode in leftover food bits (gross).

Starting Your Weld

You’ve got your electrode and machine ready to go; now you’re ready to weld.

There are three main factors to consider when doing a weld:

1. Work angle
2. Travel angle & distance
3. Travel speed

This is true regardless of whether you are TIG, MIG or stick welding. Stick welding is slightly different from MIG and TIG, though, as your stick torch starts a lot further away from the join than the others.

1. Work Angle

Your work angle is your torch in relation to the angle of the joint. There are a few different joint types, and several positions these joints can be found.

T-joint / Fillet Joint	Butt Joint	Lap Joint
90° joint angle	180° joint angle	90° joint angle
45° work angle	90° work angle	60°/70° work angle

(These angles do not include your travel angle, which we’ll talk about next.)

Positions

Flat (butt & fillet)	Horizontal	Vertical	Overhead (butt & fillet)

The main thing that your weld’s position will affect is whether or not you’ll be fighting against gravity as you go. You’ll usually need to increase your travel speed and lower your amps to keep the molten metal from dripping if you’re in an overhead, vertical or horizontal position. Keeping your arc tight will also help. While you’re learning, flat positions are best.

2. Travel Angle & Distance

When stick welding, you only want to drag (pull) your weld. If you use a push angle, you risk having slag trapped in the weld pool and contaminating the weld. To drag your weld, place your stick into the joint (if you’re welding a fillet, then your stick should be at roughly 45°) then tilt your stick slightly sideways by 10° to 15°. Your torch should hover over where you’re going to be welding, rather than hovering over where you’ve already welded.

As you weld, keep your arc length short. A good rule of thumb is that your arc length shouldn’t be longer than your electrode diameter. If you’re using a 2.6mm electrode, your arc length shouldn’t be longer than 3mm. However, you don’t want to be so close that your electrode is touching the metal, as it will stick. If you pull away too far, your arc will become unstable, you’ll produce more spatter, which will fly everywhere, and it’ll become hard to keep the arc lit.

Travel Speed

Like all welding, your travel speed needs to be consistent. The slower you travel, the fatter your weld will be (and you could go straight through if your parent metal is on the thin side). The faster you travel, the less penetrative your weld will be.

Making the Weld

Before you start a stick weld, it’s a good idea to do some dry runs to make sure that you can move with the rod as it melts and gets shorter. You can do this over the edge of a table; just imagine your weld is disappearing into a weld pool, and move along the table’s edge, slowly dropping your electrode down below it as you go.

Practising this is a good idea as you don’t want to make your arc too long. A long arc will affect your weld’s quality, and the arc will fail if it gets too far away.

It’s also a good idea to practice your arc ignition on some scrap metal. You want to scratch your electrode like you’re lighting a match and then pull up, but you don’t want to pull away too fast or too far.

The ignition can be tricky, especially if you have a difficult electrode type, as there’s also the problem of it sticking to the metal if you don’t pull away fast enough. If your electrode does get stuck, just use a fast twisting motion to dislodge the electrode from the parent metal and try again.

Place your workpiece in front of you in a way that when you begin welding, your hands can move freely and steadily. Remember that you want to be able to move downwards with the electrode.

Check that your earth clamp has been attached to a metal surface, such as a (clean) metal workbench, because if your earth clamp isn’t grounded, your machine won’t start.

If you’re making a fillet join, you can use a magnetic welding clamp to hold your two pieces of metal together.

Start with your tacks. Remember to flip your welding helmet down before you ignite your arc. Tacks are used to fuse the metals together at the edges, so you don’t have to hold them together while you’re trying to weld.

To make a tack with your stick weld, strike the electrode to ignite it and then run a tiny weld, only a few millimetres long, then pull away. You almost don’t want to move the electrode, as the tack doesn’t need to be very big. You should be able to break it off in case it’s lined up wrong. Repeat this process on both edges so that your workpiece stays lined up how you want it.

The first step in making a stick weld is igniting the arc. Scratch your electrode along your metal, quickly but not too softly (some force is needed) and pull it up and away as you scratch (but not too far). Now that your arc is ignited, you can begin to drag it along the weld, maintaining a steady pace for the best results.

If you accidentally pull away, or you don’t move down with the melting electrode, you can reignite it in the same way that you started it in the first place.

If you’re using a low hydrogen electrode and having trouble with reigniting it, you might find that the wire has burnt up slightly into the flux, leaving an empty tube of flux at the tip of your rod. Just give this a quick file to remove the excess flux, and you’ll be back up and running.

If you have the right amperage and technique, your weld should be about twice your electrode’s width (a 2.6mm electrode will produce a 5mm weld). If you finish the weld and you’ve still got half an electrode remaining, don’t throw it out!

The ability to reignite an electrode means that nothing needs to be wasted, but once you’re down to about 5cm left, you’re better off starting a new one and getting rid of the stub.

Once you’ve finished your weld, there’s one last step before you can examine how well you did. The slag removal. The protective layer that forms over your weld to minimise contamination needs to be taken off to complete the process.

You can remove the slag with a chipping hammer for the best results, and a wire brush to finish it off doesn’t hurt either. If you intend to go over the weld again and make multiple passes, this wire brush is essential in order to remove all contaminants from the weld. The type of electrode you use will also impact how easy or hard it is to remove the slag from on top of the weld.

Quick tip: Even if you’re faced with challenging slag, don’t beat at it. You’re likely to make it airborne and spray it across the room, creating a bigger mess. Instead, use the pointed end of your hammer to drag along the top and chip at the sides with the flat end, alternating with the wire brush as well to remove it.

Once you’ve removed the slag, you’re done, and you can inspect your weld. Don’t be disheartened if you’re first stick weld doesn’t look great. Getting the technique right and keeping a steady pace as you drag while the electrode melts away under you is hard.

The first few attempts will most likely be wobbly; your arc will stop and start; you’ll probably have fat parts and thin parts. All of that is fine! Just keep practising (you can use your half electrodes for practice), and you’ll be a master in no time.

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The post The Ultimate Guide to STICK Welding appeared first on UNIMIG.

Quick Navigation

Jump to:

• Tungsten Preparation
• Torch Setup
• Machine Settings
• Weld Preparation
• Making the Weld

What is TIG welding?

Tungsten Inert Gas (TIG) welding is the process in which an arc is formed between a tungsten electrode and the workpiece to join the metals together. A filler rod is often fed into the weld pool by the operator to create a weld. A shielding gas is also required to protect the weld from atmospheric contaminants that could cause weld defects such as porosity.

TIG welding is considered the most challenging type of welding to learn as there is a lot more room for human error.

Tungsten Choice

There are several different types of tungsten, each with their own unique properties and limitations.

• Pure tungsten (Green tipped)
• Thoriated 2% (Red tipped)
• Ceriated 2% (Grey tipped)
• Lanthanated 1.5% (Gold tipped)
• Zirconiated 0.8% (White tipped)
• Rare Earth (Purple tipped)

The tungsten that best fits your job will mainly depend on your parent metal and application, as not every tungsten will work with every metal. The thickness of your workpiece will also be a factor in which tungsten you’ll need.

Each type of tungsten comes in a range of diameters so that you can do precise and appealing welds. A good rule of thumb is the thicker your workpiece, the thicker your tungsten and vice versa.

If you’re just starting out and learning TIG, we recommend using the gold tipped Lanthanated or the grey tipped Ceriated. They’re both great general purpose, AC/DC compatible, and weld well on all metals, including aluminium (which is a much harder metal to work with, so don’t worry about it just yet).

You can also check out our tungsten selection guide for the full rundown on each tungsten.

Tungsten Preparation

Now that you’ve selected the tungsten that fits your job, the next step is to prepare it for the weld.

Before you start, make sure that you are prepping the non-coloured end of your tungsten. The tungstens are colour coded because they are almost identical in appearance. You don’t want to grind off your coloured end, as you won’t know what it is later.

There are a few different ways to prepare your tungsten, and different shapes will give different results on different applications.

A balled tip is usually recommended if you are using a pure or zirconiated tungsten and welding aluminium. This is a pretty easy shape to make, as you simply set your machine to the recommended amps on AC, turn it on, and the tungsten will automatically form a ball on the tip.

The other option is to set your machine to DC electrode positive (DCEP), hold the torch 90° on a piece of copper and start the arc to form a ball. This tungsten preparation method happens after you have set up your gun and machine, though, not before.

The most common tungsten shape to weld stainless and mild steel with is pointed, which produces a focused and stable arc, and works for all DC applications. To get this pointed shape, you’ll need a tungsten grinder or a bench grinder (a diamond wheel is best).

If you use a bench grinder, it needs to be dedicated to tungsten preparation, as you can contaminate your tungsten with anything that’s leftover on the grinder.

Press your tungsten vertically to the grinder at a 30° angle and rotate at a consistent pace until a point has formed. It’s essential to grind with the tungsten’s grain (lengthwise) and not against it (horizontal on the grinder) for a few reasons.

The main reason is that it lowers the number of ridges in the tip of the tungsten. More ridges mean that the arc has more surface to cover, increasing your chances of it wandering or the tip melting off and falling into your weld pool. Your tungsten will also stay sharper for longer if you follow the grain, so you won’t need to re-grind it as often.

A truncated tip follows the same preparation as a pointed tip but with the added step of grinding the end, so you get a flat top. This shape works well for both AC and DC applications.

For now, though, if you’ve opted for a gold or grey tipped tungsten, let’s stick with a 30° point.

Metal Preparation

When you’re TIG welding, your workpiece must be clean. If the metals you want to join are rusted, have paint on them, are oily or otherwise coated in some way, you’ll need to grind the metal until it’s squeaky clean. If you leave anything on your workpiece, your weld could be contaminated, and it won’t be a quality weld.

If you’re working with aluminium, your metal still needs to be cleaned, but you’ll need to prep it with acetone and a wire brush rather than grinding it. Aluminium is soft, so taking a grinder to it will ruin the metal before you’ve even attempted to weld it.

Machine Setup

1. Gas
2. Torch
3. Machine Settings

1. Gas

TIG welding requires a shielding gas to protect the weld from outside contaminants. The good news is it doesn’t matter what kind of metal you’re welding; pure argon gas alone will cover almost every TIG application, so you won’t need to swap between bottles. (You can still get gas mixtures for specific applications, however.)

TIG welding requires a flow meter so you can adjust the gas flow rate. Every UNIMIG TIG welding machine comes with the needed flow meter, which you insert into the top of your gas tank.

The flow meter has two parts: a pressure gauge and a flow tube. The pressure gauge tells you how much gas is left in the tank and the tube (which is adjusted by a valve on the side) shows you how much gas is pumping into your torch per minute.

Turn the valve so that it’s fully closed before you open your gas bottle. An 8-10L per minute gas flow is a standard amount that will cover all metal types and keep your weld safe.

2. Torch Setup

There are two different types of TIG torch that you can use. One comes with a button and one doesn’t. The type of torch that you have will determine the ways you can ignite your arc.

3 types of TIG

• Scratch start
  Scratch Start is the most basic form of TIG welding and requires dragging the electrode across the surface of a workpiece to initiate the weld cycle.
• Lift Arc
  Lift Arc requires touching the workpiece and lifting the torch to initiate the weld cycle.
• High Frequency
  A High Frequency start allows you to initiate the weld cycle by pressing a button, or foot pedal.

If you have a High Frequency torch, you can activate it with the button (or foot control), which also controls your gas. If you have a Lift Arc torch (which comes with a valve), you are limited to lift starts and scratching (however, scratching isn’t recommended as you can cause tungsten inclusions at the beginning of your weld).

Neither scratching nor lift starting will work on AC, so you must have a High Frequency torch if you’re using AC. The VIPER 180 AC/DC Mk II TIG/Stick Welder comes with a high-performance T2 TIG Torch, which is a High Frequency torch, and if you’re a home DIY welder, you’ll want to learn with the easiest arc ignition.

There are two variations of the High Frequency torch: one with only a button and one with a button and a potentiometer (pot). The potentiometer torch gives a welder more manual control over the number of amps they’re using during a weld when the welder is set to remote mode.

You can also decide if you want a rigid head or a flex head on your torch. A rigid head means the neck won’t bend, making it harder to get into tight corners. A flex head can bend, making it a lot easier to get into tight spaces and awkward angles. The VIPER 180 AC/DC Mk II & RAZOR TIG 200 AC/DC both come with flex head torches.

Standard torch sizes

TIG torches come in a number of sizes: 9, 17, 18 & 26. The 18 torch is the same size as the 17, but it is water-cooled rather than air-cooled. Each torch uses the same types of consumables (see below) but will have their own sizes that fit inside when it is put together.

A size 9 torch will have much smaller consumables than a size 26. The smaller the torch you purchase, the lighter it will be, but the hotter it will get at higher amps. Professional welders often prefer a lighter torch so that they can weld for longer before their hand gets fatigued.

On the flip side, the bigger the gun you get, the higher amperage it can take. A size 26 torch can use more power and stay cooler for longer than a size 9.

Polarity

Regardless of the type or size of torch you have, the next thing you’ll need to do is plug it in. TIG welding is always done in negative polarity, which means that the torch goes into the Negative (–) panel mount and the earth clamp goes into the Positive (+) panel mount on the front of your welder.
If you get the polarity wrong, you can burn your tungsten up into the torch, so double-checking before you start is a good idea.

After you’ve locked your torch into place, if you have a High Frequency torch, attach the power cable plug into the socket and the gas hose into the gas connector at the front of the welder to finish your torch setup.

Note: If you have a water-cooling torch, you will also need to attach the blue and red water cables to the welding machine and the water cooler so that the water can flow through the torch.

The correct polarity setup is available in our User Manual that comes with each machine (and is available online), so don’t stress if you forget.

Building your TIG torch

To set up your torch you should have:

1. Your chosen tungsten
2. Collet
3. Collet body
4. Back cap
5. Ceramic cup (gas shroud)

The collet and collet body should match the size of your tungsten (if your tungsten is 2.4mm thick, the borehole in your collet and collet body need to be 2.4mm wide).

Your ceramic cup is marked with a number indicating how large the cup’s opening is, which will determine how much gas coverage you will get to protect the weld. They also come in a variety of materials, such as Quartz (glass).

Quartz cups work the same way as ceramic cups, but they allow for a lot more visibility because they’re clear. Quartz cups use a gas lens rather than a collet body to achieve this additional coverage, so their shrouds are wider, which protects more of the weld while it’s liquid.

Gas lenses are an optional accessory on TIG torches which replace the collet body inside the torch. They’re especially useful when welding inside corners or in tight spaces because you can stick the tungsten out further thanks to the extra gas coverage.

Standard lens vs Gas lens

Standard nozzles release a broad plume of shielding gas over your weld. In comparison, a gas lens improves shielding gas coverage by distributing gas around the tungsten more efficiently with less turbulence. You can also have the tungsten stick out further with a gas lens, giving you better manoeuvrability and visibility of the weld pool. This is great for when you need to weld in tight spaces.

If you are using a gas lens, you’ll need a gas lens ceramic cup, as a standard one won’t fit. The below steps don’t change much if you’re using a gas lens.

Torch Assembly

1. Fit the collet into the collet body.
2. Fit the tungsten through the collet and collet body.
3. Screw the collet body into the torch head.
4. Screw the back cap onto the torch head. Don’t fully tighten just yet.
5. Screw in the ceramic cup onto the front of the torch.
6. Finally, adjust the tungsten to your desired length, then fully tighten the back cap.

Keep in mind that the tungsten shouldn’t stick out further than the inner width of the ceramic cup. For example, a #7 cup is 11mm wide, so the tungsten shouldn’t sit further out than 11mm from the top of the cup.

It’s okay if your tungsten is sticking out too far after you’ve screwed the back cap on; just unscrew it until the tungsten becomes loose, slide the tungsten back until it’s the correct length and then re-screw the back cap until the tungsten is snug again.

Now your torch is complete and ready for use.

3. Machine Settings

The first time you look at a TIG machine, you’re first thought might be along the lines of, ‘that’s a lot of lights and buttons’. You’d be correct. Compared to MIG and stick machines, a TIG welder can seem super complicated. Don’t stress; it’s easier than it looks. Using the VIPER 180 AC/DC Mk II as a guide, let’s run through what they do.

Starting on the far left is a column of five, with the following options:

• AC
• AC PULSE
• DC
• DC PULSE
• MMA

These are our welding process settings. MMA (manual metal arc) is also known as stick welding. All TIG welders can stick weld, so you would switch to that setting if you attached an electrode holder to your machine.

The other four options are what we use to TIG weld with. AC currents are used when working with aluminium, and DC is used for steel and stainless steel.

The AC and DC settings will provide a constant running current, while the PULSE options will give a pulsating current (imagine a flickering light bulb). The pulse options are often used for very precise or artistic welds on thinner material, as it does not penetrate as deeply.

Moving slightly to the right is a column of three options:

• 2T
• 4T
• SPOT

These stand for two touch, four touch and spot.

2T (two touch) means you will need to hold the button down on your High Frequency torch while you weld.

In 4T (four touch) mode, you will only need to click the button to ignite the arc and the torch will continue to weld until you click it again to turn it off.

SPOT is precisely what it says, consecutive and evenly timed arcs that work well if you want perfectly even tacks and small welds. If you’re using a foot pedal, you’ll need to set it to 2T as it won’t work otherwise, but more on that later.

Next up is the pyramid steps. These are the parameter settings and are the ones you’ll need to change when swapping between welds. In order from left to right, they are:

1. Pre-gas: this is the gas that shields the tungsten and area you are about to start welding from the atmosphere. Use the knob to select how long you would like your pre-gas to flow before the arc ignites.
2. Start amps: these allow for a lower or higher amp start, depending on your material. If you have a thicker piece of metal, you’ll want to start on higher amps than if you’re welding a thinner piece.
3. Up slope: your up slope will dictate the amount of time (in seconds) it will take to reach your peak amps from your start amps. The more time you input, the longer it will take for the amps to increase. A longer up slope is recommended for thinner metals to prevent burning straight through.
4. Peak amps: these are the amps you will do your welding on until you have finished the joint. If you are set to AC/DC pulse, this will be the high part of your amp cycle.
5. Base amps: you will only use base amps in PULSE modes. This is the low part of your amp cycle. The closer your amp range from peak to base (e.g. 80 peak – 70 base), the hotter your weld will be. The more significant the gap (e.g. 100 peak – 70 base), the cooler your weld will be.
6. Down slope: your down slope will dictate the time (in seconds) between your peak amps and your finish amps. This will taper the arc to prevent crater holes and cracks in the weld.
7. Finish amps: this is the final amp level that the machine will reach before your arc extinguishes. If you turn this up, it will be a hotter finish, suited to thicker materials. Turning it down will provide a cooler finish suited for thinner materials.
8. Post gas: this is the gas that flows for a set time once your arc has turned off, to shield and cool the tungsten as well as the weld. The longer you leave this on, the less likely you are to have pinholes and craters. The thinner the metal, the less time it needs to be on.
9. AC Balance: this is automatically calibrated based on your other parameters; however, you can manually adjust it. If you set it to above 0, you will increase the cleaning but decrease the penetration, and if you set it below 0, you will decrease the cleaning and increase the penetration of the weld. (Only for AC & AC pulse.)
10. AC Hertz: this is the number of times per second that the current completes a full cycle. If you turn this up, it will increase the cycle speed and create a thinner, more prominent weld appearance as the arc will be more focused. The lower you turn this, the flatter your weld will be. (Only for AC & AC pulse.)
11. Pulse Hz / Pulse %: Pulse Hz is the number of times per second the current cycle will switch between peak amps and base amps. The faster the amp switches, the narrower the weld. (AC/DC pulse only.) Pulse % is the percentage of time the peak amps are on during the pulse cycle. A high percentage will have a hotter weld, and a low percentage will have a cool weld. (AC/DC pulse only.)
12. Arc force / Spot: this is only for stick welding (MMA) and helps with the penetration of the stick weld; the higher this is, the more penetrative the weld. This will only be available if you have set your machine to ‘Spot’ mode and is the timer you’d like to have your arc last for during each tack or small weld.

On the right side of the adjustable knob are three lights:

These lights won’t always be illuminated, and you definitely don’t want the parameter warning light to be on.

Remote: this light will turn green if you are in remote mode. You can activate remote mode on the High Frequency torch. Turn it on by holding the button on your torch down for 5 seconds until the machine beeps and the light turns on. Remote gives you more manual control over the amps; however, a foot pedal can only be used in 2T mode, as letting go of the pedal will kill the arc.

Tungsten Electrode mm: input your tungsten width here. The machine will only provide a limited number of options, as there are only so many tungsten sizes. You can navigate to this setting with the control knob.

Parameter Warning: this light will turn yellow if you’ve put in amp settings that the machine thinks are too low for your tungsten. If you have told the welder that your tungsten is 2.4mm and then set your peak amps to 40, this light will come on to let you know that you’re going to have a weak arc.

Mixed Arc AC/DC Welding

Mixed AC/DC welding is the combination of TIG AC and TIG DC- in one weld. There are quite a few benefits from this type of weld, including higher welding speeds and penetration, and a faster weld puddle on cold workpieces. Mixed AC/DC also means that you can weld on thicker materials.

There are two periods during a mixed weld. The first is the AC period, where the oxide film is broken and surface impurities are flushed out. Second, the DC- period, where the arc becomes narrower and penetrative. The operator can select the percentage of AC and DC- during a full period, which can be varied from 5-95%, though it’s a good idea not to have more than 50% DC-.

This feature is pretty specialised, though you can find it on the RAZOR MULTI 230 AC/DC, RAZOR TIG 200 AC/DC and the RAZOR 320 AC/DC welders.

Filler Metals

The second part of TIG welding is your filler rod – the metal you’ll be using to feed into the weld pool. You need to match your filler rod metal to your parent metal, as dissimilar metals only weld together if you have the right filler. These rods usually come in 50cm or 1m lengths, so it’s a good idea to cut them down to a comfortable size as it’ll make it easier to feed.

There are a few different classifications for each type of filler rod available.

Steel Rods:

• ER70S-2: best quality and most common
• ER70S-4
• ER70S-6

Stainless Steel Rods:

• 308L: mainly used on austenitic stainless steels
• 309L: used for welding dissimilar metals
• 316L: marine grade, recommended for anything that will be used in water, will only weld to 316 graded parent metal

The ‘L’ refers to the extra low levels of carbon in the rods, which helps prevent corrosion in the welds.

Aluminium Rods:

• 4043: use on 4000 to 6000 series aluminium, contains silicon
• 5356: use on 3000, 5000 & 6000 series aluminium, marine grade, contains magnesium

Just like with your tungsten, you want your filler rod size to fit your workpiece size. A good rule of thumb here is to match your rod size to the tungsten. Let’s use an example: 3mm steel. You’ll be using a 1.6mm tungsten on this metal thickness, so a 1.6mm filler rod will be perfect.

Starting Your Weld

Once your equipment is all set up, you’re ready for the fun part: starting a weld.

Three main factors need to be considered when doing a weld:

1. Work angle
2. Travel angle & distance
3. Travel speed

This is true regardless of whether you are TIG, MIG or stick welding.

1. Work Angle

Your work angle is your torch position in relation to the angle of the joint. There are a few different joint types, and several positions these joints can be found.

T-joint / Fillet Joint	Butt Joint	Lap Joint
90° joint angle	180° joint angle	90° joint angle
45° work angle	90° work angle	60°/70° work angle

(These angles do not include your travel angle, which we’ll talk about next.)

Flat (butt & fillet)	Horizontal	Vertical	Overhead (butt & fillet)

The main thing that your weld’s position will affect is whether or not you’ll be fighting against gravity as you go. While you’re learning, flat positions are best.

2. Travel Angle & Distance

TIG welding is always done at a push angle. A push angle means your torch is over the weld, and you push the weld pool along the joint. Dragging (pulling) while TIG welding won’t penetrate or properly cover your weld, resulting in porosity in the joint as the gas from your cup won’t reach the liquified metal.

You also want to keep your torch at a 75° angle as you push. If you’re welding in a fillet joint (a corner join), your torch will be angled into it at a 45° angle, then you’ll angle slightly to the side so that your gas can cover the weld pool and in front of the weld as you go.

The filler wire will be in whichever hand is not holding your torch. Your filler wire should come in from relatively low, almost parallel with the joint, with a slight 10° to 15° angle (back end in the air) when it is introduced.

The distance between the tungsten and the weld is also something you need to watch as you go about your weld. The best length to keep your tungsten from the workpiece is around 3mm. This will give you the best control over the arc and your weld. It also gives you space so that the filler rod is unlikely to touch the tungsten.

If your torch is angled too far or is too far away from your workpiece (creating a long and unstable arc), you will likely have a weld with much more oxidation. The filler wire also won’t melt into the joint because there’ll be a lack of heat.

If your tungsten touches the weld pool, then you’ll have to stop the weld and re-grind the tungsten. If you do touch your tungsten into the weld pool, don’t try to snap it off. Turn your torch off without moving it and allow it to cool slightly. Then you can loosen the back cap of the torch and simply slide the tungsten out. This way, you don’t risk damaging the collet body inside your torch.

Travel Speed

Travel speed is how fast you are moving the torch along the weld. The speed you travel affects how far the weld penetrates. Too fast, and it won’t go far enough, too slow, and you could burn a hole straight through. Your travel speed also dictates the weld’s conformity; if you’re speeding up or slowing down, then the weld won’t be even.

Keep your travel speed consistent! This applies to all types of welding. Inconsistent travel speed or incorrect travel speed will result in a bad weld.

Making the Weld

Place your cleaned workpiece in front of you in a way that when you begin welding, your hands can move freely and steadily, and you can comfortably complete the joint. It’s a good idea to have something to steady your hands against as they go along the weld so that you can maintain your angle and distance.

Check that your earth clamp has been attached to a metal surface, such as a (clean) metal workbench or the workpiece, because if your earth clamp isn’t grounded, your machine won’t start. If you’re making a fillet join, you can use a magnetic welding clamp to hold your two pieces of metal together. Aluminium isn’t magnetic, however, so a manual clamp will be needed.

Start with your tacks. Remember to flip your welding helmet down before you ignite your arc. Tacks are used to fuse the metals together at the edges, so you don’t have to hold them together while you’re trying to weld. This is especially important when TIG welding as you don’t have any free hands.

Hold your torch in your dominant hand and your filler rod in your other hand. Press the button on your torch to start the arc (keeping pressure on it in 2T mode) until you see a wet pool forming. Dab a small bit of filler rod into this pool and then release your button. You’ve just made your first tack.

Repeat this process on both edges so that your workpiece stays lined up how you want it. If the metal you’re welding is completely flush, and there is no gap at all at the join, you can get away with just fusing the two pieces together with the torch for your tacks. With your tacks done, you can remove the magnetic clamp.

To make the weld, start the same way as you did to make the tack. Press the button (holding it down if you need to) until the metal begins to pool. Then dab the filler wire into the leading edge of the weld pool. You don’t want to touch it onto the tungsten in the middle of the arc. You are aiming to push the filler wire into your pool to make the best weld.

When adding filler wire, a good rule of thumb is to add the same amount on each dab as the wire’s width. For example, if your wire rod is 1.6mm in diameter, you want to add about 1.5mm of the rod into each dab. Also, make sure you’re feeding the filler rod into the pool in sections rather than constantly holding it in. Take pauses between each dab to let your weld pool reform.

Once you’ve run your weld, release the button, and the torch will cool down and then pump your post gas out over your weld. Having this ‘post flow’ over your weld as it cools will help to keep it free of contaminants, but you’ll need to remember to keep your torch over the weld for this to work. It’s super tempting to pull your hands away immediately to check out your weld, but you’ll lose your post flow if you do.

Congrats, your weld is done, and you can now take a look at your handiwork. A good TIG weld should look like an even and straight stack of dimes with no porosity or other signs of contamination when you’re done.

Fusion Welding

Fusion welding follows the same process as previously described, except you don’t add any extra metal. This is nowhere near as strong as a standard weld, and so it’s best to use it for practice only. It’s a great way to get a feel of the TIG torch while you’re still learning, and you can fusion weld on your scrap metal to practice creating consistently sized weld pools and running beads.

Back Purging

If you’re going to be welding on piping or tubing, then it’s a good idea to back purge as you go. Back purging is the process of shielding the back of your weld from carbide precipitation (your metal reacting to the atmosphere).

If you don’t shield the inside of your pipe, the weld’s backside will look like it’s covered in granules (which is why this is called ‘sugaring’), and it means your weld will be prone to cracking. In simple terms: it’s a failed weld.

To back purge, first, you’ll need an extra gas tank, or a dual regulator, as you need to pump gas to your torch and into the pipe at the same time, but at different flow rates, which requires two hoses.

Plug up the ends of your pipe – you can get specifically designed purging plugs for this – or tin foil works as well if you’re on a budget (glad wrap doesn’t work, it’s too weak to hold the gas in).

It’s essential to make sure you have a ventilation hole on either end, as you need to insert your gas hose in one side and have an exit hole for the atmospheric gas to escape. If you don’t leave a vent hole, the gas will make its own as you reach the last part of your weld and it becomes trapped.

If you’ve purged correctly, your weld should be smooth inside and look similar to the outside weld. This can take a bit of fiddling with because your pipe size and the material will determine how much gas you need to be pumping in to cover the weld fully. There’s no one size fits all rule with this.

The best way to get better at something is to practice, practice, practice! You can make dry runs as many times as you need to feel comfortable with the motion before starting an actual weld.

If you’ve got some spare or scrap metal, you can practice making beads on the parent metal (make a weld pool, push it along the metal at a steady pace, repeat) without adding any filler metal (fusion) to practice the torch motion and to get a feel for how long it takes for the pool to form each time.

Once you’ve got the hang of making a clean, quality TIG weld, you can play around with the gas and other settings to make more colourful and artistic welds.

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Quick Navigation

Jump to:

• Machine Setup
• Torch Setup
• Weld Preparation
• Making the Weld

What is MIG welding?

Metal Inert Gas (MIG) welding is an arc welding process in which a solid wire (the filler metal) is continuously fed through the welding machine and into the weld pool that’s created by the arc to form a weld.

The process of MIG welding is semi-automatic, as the machine does all the wire feeding for you. This is why MIG welding is considered one of the easiest types of welding to learn and a great place to start for beginners.

Machine Setup

1. Gas vs gasless
2. Rollers
3. Torch
4. Wire spool
5. Voltage/wire speed setup

1. Gas vs Gasless

There are two ways to MIG weld. The first (and most common) is with gas. The gas is used to shield the weld metal from any outside contaminants when welding. The second is gasless, and the filler metal used has a flux core, which protects the weld instead of gas.