TIG welding
What settings for 3 mm steel on TIG?
Quick answer
For 3 mm mild steel on TIG: 90–130 A DCEN with a 2.4 mm tungsten and 2.4 mm filler — enough to establish the pool fast and travel before the heat spreads.
Settings table by thickness
| Thickness (steel) | Current (DCEN) | Tungsten | Filler rod |
|---|---|---|---|
| 1 mm | 30–60 A | 1.6 mm | 1.6 mm |
| 1.5–2 mm | 50–90 A | 1.6–2.4 mm | 1.6–2.4 mm |
| 3 mm | 90–130 A | 2.4 mm | 2.4 mm |
| 6 mm | 150–200 A | 2.4–3.2 mm | 3.2 mm |
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.