All things welding

[freedom_in_4low]

For a lap weld that wire in that size will be fine.

Personally whenever I weld exhaust behind the cats with either aluminized or stainless or whatever, I never change wire or gas. I just don't care enough & I don't want to keep different spools or gas just for welding those materials because I don't weld them enough. Also it's not structural, it just has to hold itself together. I always take a flap disc to the weld mainly to see if I have complete fusion along the entire length of the joint & because the welds usually look like shit because I'm not good at welding very thin metal yet.

Most of my experience is with fairly thin stuff, like when I did the railing around my stairs. I tried body metal once but it wanted to burn through, that definitely needs something like .023. especially since I was filling in a crack, so effectively a butt weld. If exhaust tubing wasn't quite a bit thicker than that I wouldn't even think about trying it.

 

[NashvilleTJ]

For a lap weld that wire in that size will be fine.

Personally whenever I weld exhaust behind the cats with either aluminized or stainless or whatever, I never change wire or gas. I just don't care enough & I don't want to keep different spools or gas just for welding those materials because I don't weld them enough. Also it's not structural, it just has to hold itself together. I always take a flap disc to the weld mainly to see if I have complete fusion along the entire length of the joint & because the welds usually look like shit because I'm not good at welding very thin metal yet.

I’d add that you also don’t need to worry about sugaring on the inside of the stainless behind the cats. And I would think that’s not an issue at all with a lap weld.

You would definitely have to worry about sugaring on the intake side on a butt weld. But dealing with that is a whole ‘nother can of worms.

 

[freedom_in_4low]

I’d add that you also don’t need to worry about sugaring on the inside of the stainless behind the cats. And I would think that’s not an issue at all with a lap weld.

You would definitely have to worry about sugaring on the intake side on a butt weld. But dealing with that is a whole ‘nother can of worms.

good to know. Having zero experience welding stainless I had to google what sugaring even was, but now that I know I agree I don't think I need to worry for this. I do know I'll have to paint the weld to prevent corrosion.

I was more thinking about whether there was gonna be any quality issues with the weld due to the different compositions as I feel like I've heard of people (using gas shielded or stick) using specific filler when doing stuff like this, but since no one has brought that up I guess I'm ok, or at least ok enough for exhaust tubing.

 

[AirborneTexasRanger]

good to know. Having zero experience welding stainless I had to google what sugaring even was, but now that I know I agree I don't think I need to worry for this. I do know I'll have to paint the weld to prevent corrosion.

I was more thinking about whether there was gonna be any quality issues with the weld due to the different compositions as I feel like I've heard of people (using gas shielded or stick) using specific filler when doing stuff like this, but since no one has brought that up I guess I'm ok, or at least ok enough for exhaust tubing.

The wire you mentioned in your original post will be fine. Lincoln NR211MP

For practice, if you want, you can minimize sugaring by welding the stainless in small bits ~1/2" at a time then let it cool. Sugaring, technically oxidation, is the result of excessive heat applied to stainless steel.