MIG welding exhaust?

[Bgbkwndo]

I would like to MIG weld Type 409 - 14 Gauge Stainless Steel exhaust tubing, and need to know what type of wire to use? I surmise that pure Argon shielding gas is required.
What wire diameter is preferable?
Any info on the subject is much appreciated.

Bgbkwndo.

[DSW]

100% argon is usually only used to mig weld alum. All the stainless mig I've done was either with trimix or just plain 75/25 when the weld quality didn't have to be great. For 14 ga I'd probably work with .023 wire or .030 depending if I thought I might need to weld thinner or thicker material as well. Never done 407 so I can't help with filler other than I know it's just barely stainless. All my stuff was 304 or 316.

[BCRD]

Download this PDF (from lincoln website)

http://content.lincolnelectric.com/pdfs/products/literature/c64000.pdf

You have 2 choices ER409 and MC409. The MC409 is .045 and requires 98% argon / 2%O2. Other brands will have their own versions.

Jason