ding

[mikelutestanski]

Hello:    check with airgas & fabricator.com (any gas supplier will do)   to see what gas works with what metals.  They Do give a shield gas for SS to Carbon steel.   Argon with 25 to 35 % He with 1 or 2 % co2.   
    You can find all sorts of tips on the web.
       One welder said he uses 75/25 gas  argon co2 but he limits his SS welding to 1 pass to hold down excess heat build up. 
     My solution for the rusting problem when welding with a mig is to make sure that you bury the carbon welds with SS weld but there again  the gas may be an issue..
    Anyway lots of info out there to get the job done.
    Regards and Happy bussin   mike