do you need a tig to weld stainless? or can you do it with a mig? i need to get my new stainless exhaust welded soon. ive heard many different answers to this question, and was hoping someone could clear it up. thanks in advance.

 

funny you should ask. I was just told by a welder of about 10 years that u can do it with a mig, but it doesn't look good. The welds are strong but it doesn't look nice. (i dunno what he ment, maybe discoloration?)If you tig welded it it would be strong and it would look good.

 

thermal exhausts are mig welded and they are stainless... it does look pretty bad... tig welded stainless just looks so much nicer

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ek9t &raquo;</TD></TR><TR><TD CLASS="quote">thermal exhausts are mig welded and they are stainless... it does look pretty bad... tig welded stainless just looks so much nicer</TD></TR></TABLE>

Yep, I just noticed that on thermal that was on a teg yesterday. They do 3 separate welds instead of just one clean continuous weld.

 

well tig is just easier to blend and make it look like one continous weld, were is it just alil harder with mig.

 

i have welded on stainless and it looked like crap but i dont have that much experance. my buddy that has like 10 years experance welded some stainless for me it didn't look as good as i thought it would have. so yeah i guess that is true that mig on stainless doesn't look good. but then my buddy also stick tig welded some stainless and it didn't look alll that hot either untill he just used the wand by its self to bond the two pipes together and that is when it looked bad ***. but i have seen stick tig welds that have looked really good though.

 

damn ti i want pix

 

it all depends on the thickness of the material you're welding. Stainless has the tendancy to 'burn' if you're using too much heat, and the downside to mig is that depending on the wire you use, you'll most likely be putting in more heat as compared to tig. I've done alot of mig on stainless, mostly thicker plate (1/4" and up) and most times the bead will look almost like it was welded with a stainless rod. make sure you're using the proper shielding gas. C02 with a heater on the bottle is what you want for stainless mig.

 

I've MIG'd stainless piping with good results. I actually felt my mig welds on stainless tubing were better than my welds on aluminized steel (prepped).
In any case, I found the technique was very similar to welding mild steel and the beads looked good as well, they just stood "up" a little bit. I used a tri-mix of argon/co2/helium and stainless wire.

Ben