Thick metal welding, dirtier material. If you are working on thin metals, hvac, doing frame-outs, go with a TIG welding process, if you want a wider range and you are going to be working indoors, MIG welding is probably what you are going to want. Now let’s get a little bit more specific about what metals you can use for each process.
MIG will typically have the ability to weld steel, stainless steel, and aluminum alloys.
Stick has the ability to weld on steel, stainless steel, and cast iron.
Whereas TIG pretty much runs the gamut. You can weld on any metals that conduct electricity; steel, stainless steel, aluminum, copper, brass, chromoly and exotic metals such as magnesium and titanium.