On Mon, 21 Jan 2008, Ron Childers wrote: > Plain ol the Co2 works for mild steel. 1/2"? What kind of mig welder do you > have? Ron C > > Well, my Millermatic 251 is rated to be able to weld 1/2" in a single pass. Nice machine. I'm currently using C25 (25% CO2 / 75% Argon) gas on steel.