MIGging stainless exhaust
 

I have a little 110v MIG machine (Lincoln 140C), a bottle of 100% argon, and a bottle of C25. I want to add a resonator to my stainless Enthuza 3". I'm reading conflicting info on whether this can be done well. I had good results with the mild steel downpipe but apparently stainless needs more juice. Anyone done it with similar equipment? What wire and gas did you use?

You can use normal wire and gas, but the welds will rust. I would suggest trying to get it tigged

I plan to do the same thing with my Linconln 140c. My plan of attack is to use Lincoln Blue Max MIG 308LSi wire and experiment with what little 75%-Ar/25%-CO2 gas I have left. From what I've been reading an Ar/Co2 mix with ~2%CO2 should work much better. Let me know how the 100%Ar works.

used an off brand flux core welder on stainless, welds worked fine but yeah, they rust.

Being impatient I decided what to buy based on what Amazon would ship me before the weekend, so I just ordered a Vibrant 1142 3" Ultra Quiet Resonator and a spool of US Forge Welding Stainless Steel MIG Wire .030 2-Pound Spool #00676 . I'll give that a shot with the 75/25 first since that's what they recommend and see how it goes. Maybe I will try purging with the argon at the same time.

Interesting.. I was plaining on miging mine as well. i have 304 exhaust mani components and 308 wire (as suggested by airgas employee) and 100% argon. they said tri mix would work best but argon would probably do fine.

Tig ( for looking best job ) and 100% argon for stainless:2cents:

lincoln handy mig 110V welder
stainless steel
I think 308L wire and 75/25 mix gas.

http://farm4.static.flickr.com/3064/...3d6e26ce_b.jpg

next you can swap the polarity and weld some aluminum with straight argon.

Please note the thread subject does not say "should I MIG or TIG my stainless exhaust?" :)

If I had the shop space I'd have a TIG for sure, but I have a one car garage and it's already busting at the seams.

Answer, yes you can mig stainless, its just not as clean and it will rust.

Great, thanks for the report.

I have a spool gun for my 140 and that's why I have the tank of argon in the first place. Have yet to produce a pretty aluminum weld, but I have stuck a few pieces of thin aluminum together.

Just spray some high temp paint over it and call it a day

This is a common attitude here I know, but for some of us it's not any fun unless we at least try to do it right. Building something nice is kind of the point...

I haven't had rust issues yet FWIW. you could probably use a more resistant wire but I don't know which that is. And it's probably harder to use.

I finally got around to adding a resonator to my stainless exhaust. It was really easy. Just like working with mild steel. And holy shit my car is quiet now! The difference a little 10" long resonator makes is amazing.

https://s3.amazonaws.com/kdaymisc/resonator.jpg

I used 308 wire (.030) and tri-mix gas (which was kind of pricey).

I guess i'm fucking old school because last time i had to weld up some stainless i just broke out the tried and true Lincoln 110 ARC welder i have and used stainless rods lol

How is the fit in the tunnel? I'm having issues with the rear longitudinal bracing as is. Do you notice any increase in spool time?

You can buy stainless wire to use with a mig spool gun and it shouldnt rust.

I havent tried it myself, so I cant say for sure... But more experienced people have told me to use 100% argon with stainless mig. As well as to Never use flux core as it will cause the welds to rust quicker as well as it is never as clean as gas welding.

Correct on the argon gas

Flux core doesnt rust faster, but will rust like any steel weld. but it spatters like a motherfucker. Have to coat the area around the weld area with anti-spatter to get a clean weld.

The way it was explained to me with Flux Core is its basically an acid or solvent core that is used to clean the metal you are welding to. But it also creates a lot of spatter (hence use anti-spatter) and leaves a residue over everything.

I never bothered with flux myself, just went right to gas welding. Ive watched someone use flux and it was a mess, I dont see a point if you can get gas.