Troubleshooting

Why is my mig welding distortion / warping?

Quick answer

Distortion / warping in mig welding usually means uneven heat input across the joint. For this process, tack sequence and backstep before touching anything else.

· · Technical guidance compiled from trade practice and manufacturer data; our source-verification program is in progress — see our editorial policy.

The specific fix

Tack sequence and backstep. The general rule: tack in sequence, backstep weld, clamp to a strongback, allow for shrinkage.

Process checklist

  • Stick-out too long — keep 8–10 mm from nozzle to work for a stable arc
  • Travel too slow on thin sheet, burning holes instead of building a bead
  • Wrong wire size for the job — 0.9 mm covers most hobby work in Australia