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This is our third welding guide and it’s no coincidence that TIG is the last process we tell you about. We can’t definitely say that it is the easiest but it is certainly not impossible.
If you love DIY and you really want to put yourself to the test, then read this guide carefully and learn how to TIG-weld. If, instead, you are still learning to weld and are looking for something simple, we recommend reading the articles on how to stick-weld and how to wire-weld.
We know what’s going through your head: “If TIG welding is not easy, so why should I learn to weld with this process?”
With TIG welding you create a healthy joint, that is you join two pieces of metal without inclusions, that is without slag residue. This process is considered “clean” and is therefore ideal for noble materials such as stainless steel and aluminium.
The answer to the question that’s in your head is clear to you too by now: learning TIG welding is useful for projects with stainless steel and aluminium workpieces. So, let’s see what materials you can use besides these.
What materials can you weld with a TIG welding machine?
Certainly stainless steel and aluminium, as we have just seen, but also iron.
They all require an electrode and a rod: the former is essential because it creates the electric arc, which is the essential condition for welding to start and be feasible. The rods, instead, are used to give the joint the filler material (which we remind you is what you add to create a joint between the metal workpieces).
Welding aluminium using TIG always requires the use of both. Same with iron. The only exception is the third material. To TIG-weld stainless steel, you can just use the electrode without the rods. When? If you have two thin workpieces, then you can also do without the filler material (the rod). If, instead, you are welding thick workpieces and your project needs a robust structure, then you’ll need rods.
How to TIG-weld: start with the right electrode.
TIG welding electrodes are different from the ones you use for stick welding. In choosing the right one, you have to pay attention to two things: the diameter and the alloy.
The diameter of the TIG electrodes: depending on the diameter, the electrodes can withstand a certain current. With the wrong diameter, you risk that the electrodes do not have the desired life and that they project their pieces onto the joint, making it brittle and therefore at risk of breaking. That’s why you should choose the electrode according to the current used in TIG welding. Follow our advice:
- Diameter 1.6 Ø: max. 80 A
- Diameter 2.4 Ø: max. 160 A
- Diameter 3.2 Ø: over 160 A
The alloy of the electrodes: to help you choose, look at the coloured band on one of the two ends: the green coloured electrodes are for aluminium, all the others are good for steel and iron.
Be careful of those with the red band because they contain 2% Thorium, which is radioactive. It’s important that you know this because when you sharpen it, it’s easy to inhale the dust.
That’s right, we really wrote “sharpen”. In fact, another important thing you need to know is that TIG welding electrodes need to be sharpened. The tip should be perfectly tapered so the electric arc will be tight and the weld will be thinner and easier to clean.
You’re wondering how to sharpen an electrode, right? You can do it two ways:
- with a grinding wheel, a handy do-it-yourself tool, which in this case can once again help you. But you need to watch out for the dust that is released. It is important that you are safe and therefore in this case use a mask (those designed for DIY) or a fume extractor.
- with appropriate sharpeners, which are tools suitable for this purpose and which for this reason are also able to recover the dust and keep you safe.
TIG welding rods: which to use?
Rods are the filler material for TIG welding that allow you to create the joint, so they have to be made of the same material as the workpieces you are welding.
You can easily recognise iron rods because they are copper-coloured, a component that helps keep them from rusting.
The most common stainless steel rods for DIY projects are made of 308 or 316 alloy. Also consider this exception: you can use stainless steel rods on iron because the performance is the same, but you can’t do the opposite. Also, if you choose to use iron, then you’ll have to paint it, so using a stainless steel rod is a bit of a waste – plus any paint doesn’t stick well where there’s stainless steel.
The aluminium rods you can use are the ones with Al-Si5 or Al-Mg5 alloy.
What do you need for TIG welding?
In addition to electrodes and rods, you’ll need a TIG welding machine, of course! Note that you can find two types.
AC/DC (Alternating Current/Direct Current) TIG welding machine: in AC mode you can TIG-weld aluminium (with HF ignition, see below). In DC mode you can weld iron and steel.
DC TIG welding machine: having only direct current available, you cannot weld aluminium with TIG. These machines can only TIG-weld iron and stainless steel.
Furthermore, TIG welding machines also differ in the type of ignition, in less technical words, how the welding “starts”.
Lift TIG welding machine: To create the TIG arc, the electrode must touch on the material and then move away. All multiprocess welding machines have a “lift start”. As you can imagine, to weld with these machines, you need a lot of manual skill, or at least some welding experience.
HF TIG welding machine: you just press the button on the torch to ignite the TIG arc. It is more effective in spot welding and much easier to handle from a manual point of view.
In addition to your partner in DIY projects, make sure you have everything you need with you to weld safely: a welding mask, gloves, mask or extractor (as you saw above) and appropriate clothing.
You’ll also need a cylinder for TIG welding machine, that is an argon gas cylinder, and a pressure reducer for the latter. Go to the page dedicated to welding accessories and you’ll find the MisterWork cylinders that you can use with our do-it-yourself welding machines. Easy, right?
Tricks for TIG welding
Cleanliness is important in welding and the first trick is soon revealed. Cleaning the workpieces is essential to avoid welding defects, even with this welding process.
If you weld stainless steel, use the stainless steel brush and use it only for cleaning this material and not for others. The risk of using the same brush that you used for iron is to pollute the weld and cause it to rust (technically we speak of a pitting effect). If you use a grinding wheel, choose the special discs for stainless steel or the zirconium flap disc.
The last piece of advice we want to give you on TIG welding is: choose the welding machine that’s easiest to use. So, between lift TIG and HF TIG, choose the latter. Also consider using a do-it-yourself welding machine, that is one designed specifically for hobbyists or small repair projects, rather than a professional welding machine.
Our welding machines are just like that: easy to use even for those who don’t weld for work. Have a look at helviLITE’s TIG welding machines: tigMAKER (which welds in HF TIG, lift TIG and also stick mode) and multiMAKER (with lift TIG welding as well as stick and wire welding). Both are DC welding machines, therefore you can’t TIG-weld aluminium but only iron and stainless steel.
To weld aluminium with our machines you can use stick or wire welding machines. To learn more, read the article that explains how to weld aluminium.