If you'd like to MIG weld aluminum with your wire feed welder, this step-by-step tutorial will show you how.If you haven't yet mastered MIG welding mild steel, then you probably need to do that before you start aluminum welding with the GMAW (MIG) process.When MIG welding aluminum, you use the same gun angle and gas flow rate (20-30 CFH).However, that's pretty much where the similarities end.