Mig Weld 304 Stainless Steel?

[Steve M]

When I did mmaw on 1.6mm we used a 3mm electrode on low amps if I remember rightly, as it fills in the holes quicker. You've got to be quick though. I was told that using 2.5mm rod leaves too many holes behind. That's what my lecturer told me anyway. It worked ok so I was inclined to trust that for Mild Steel welding.

That said, I've only ever welded stainless with TIG, and that system is is the go, definately.

Tack with MIG and then TIG from there.

[Ribfeast]

We used a mild steel gasless mig for my stainless intercooler piping. Looks shit, and rusts after a few weeks. Penetrates OK though. I just buffed it shiny then sprayed it with clear coat paint to protect from rust. Works OK

[JP]

I've just tig'd up some 1.6mm wall stainless cooler pipes for a mate that tack welded them with an ARC welder and stainless rods... was a pain to fill the holes the ARC left behind. Tacking with a MIG and then getting them TIG'd would be the go.