MIG welding
What settings for 3 mm steel on MIG?
Quick answer
For 3 mm mild steel on MIG: roughly 110–150 A on 0.9 mm wire at 12–15 L/min gas — set voltage and wire speed as a pair, watching for a consistent crackle, not a spattery hiss.
Settings table 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 |
Dialling it in
Start at the middle of the band on scrap of the same thickness. Listen: a consistent bacon-crackle means the voltage/wire-speed pair is right; hissing spatter means mismatched. Watch the wetting at the toes — a bead sitting proud on top is too cold; one digging in and undercutting is too hot.