MIG welding
How does mig welding work?
Quick answer
MIG welding (GMAW — Gas Metal Arc Welding): a continuously fed wire electrode melts into the weld pool under an argon-CO2 shield. It's the process most Australian workshops default to for general steel fabrication.
What's happening at the arc
In MIG welding (GMAW — Gas Metal Arc Welding), an electric arc (or, for laser, a focused beam) delivers intense localized heat that melts the base metal and, where used, the filler. The shielding gas — an argon-CO2 mix (Argoshield-family) or 100% CO2 — keeps air off the pool; without it the weld goes porous and weak.
Where it fits in Australian workshops
Most Australian hobby MIGs run from a standard 10A power point; 15A circuits unlock the 200A+ class for structural work.
Settings by thickness
| Thickness (mild steel) | Current | Wire | Gas flow |
|---|---|---|---|
| 0.8–1 mm | 40–60 A | 0.6 mm | 10–12 L/min |
| 1.5–2 mm | 70–110 A | 0.8 mm | 12 L/min |
| 3 mm | 110–150 A | 0.9 mm | 12–15 L/min |
| 6 mm | 180–240 A | 0.9–1.2 mm | 15 L/min |
| 10 mm+ | 250–320 A | 1.2 mm | 15–20 L/min |