MIG welding or TIG welding, here are their common points and differences to help you make the choice. Please note that MIG stands for Metal Inert Gas and TIG stands for Tungsten Inert Gas.
Common points of MIG and TIG welding
MIG welding, like TIG welding, are electric arc welds. This involves raising the temperature of the two steel parts to be welded to their melting point, using an electric arc that is created by an electrode and a gas supply. Electricity flows through the metals, creating heat and generating a molten pool.
The assembly is protected against oxidation during welding and you add a filler metal with a rod to reinforce it (not mandatory for TIG welding).
MIG welding can be applied to any aluminium or steel structure, regardless of its thickness. It does not require sanding and cleaning your parts beforehand. Your reel gun is powered by a metal electrode which is packaged as a coil. You create protection around your weld area, thanks to the gas emitted by your gun.
It is also the gas that guarantees you a continuous weld, which is why MIG welding is fast. You can use it on all metal surfaces, including the thinnest materials.
Once your electric arc is obtained, you unwind your filler metal wire at a constant speed, in order to incorporate it into the molten bath. This generates a weld bead between the metal of the parts to be welded and the filler metal, which is placed under gas protection.
You modulate your action by controlling the unwinding speed of the filler wire and the gas flow. Depending on the work to be carried out, you choose a larger or smaller diameter of the electrode wire.
TIG welding is more professional, but more complicated. The result is also much more aesthetic. You can use it on all types of metals, including aluminium and steel. You are guaranteed to obtain a robust and more corrosion-resistant finish.
TIG welding appears to be a bit more complex. The gas used is generally argon and the welding is carried out under protection of this inert gas using a non-fusible electrode. However, over time, the tungsten electrode becomes dull and needs to be sharpened, like you sharpen a pencil. It must therefore be changed sometimes.
The temperature of the TIG welding arc is between 3,400°C and 4,000°C.
The differences between TIG welding and MIG welding
For both types of welds, you can work with steel of quite different thicknesses and you can adopt any position.
With MIG welding, you weld faster and deformations are limited. It is simpler and requires less training to practice. In addition, you can automate the process, the manual mode being quite difficult to learn. MIG welding requires you to use a filler metal, which is not required with TIG welding. The size of the torch is quite large, which can complicate your task. You must be careful of projections and protect yourself well.
With TIG welding, the work is slower, but you end up with more careful and precise work. That is why it is better to use it for all visible welds and decorative elements. You must, however, better prepare your site and conscientiously clean your parts. It is also the most expensive process.