[jlwdvm]

If I order a stainless exhaust system (409) can I weld that stainless pipe with my mig welder just like regular aluminized pipe?

[Tom Hand]

JL,
Sure, with the right rod and settings and gas you can. We welded lots of pipe and mufflers with the MIG. Looks different then a TIG-made weld of course but way better than the old arc weldign or simple brazing with an oxy-acetylene torch!

[jdw_poncho]

The stainless wire used in a MIG welder will be softer than carbon wire. Make sure you keep the leads as straight as possible. I use straight argon when welding stainless, not 75-25 like you would normally use for carbon steel. The weld will be ugly after welding, but they make cleaners you can brush on and let sit to polish it back up. Stop by a welding store and ask for weld brite or any other brand of stainless cleaner. They should know what you need. If you use a wire brush to polish it instead of a chemical make sure you use a stainless brush that hasnt been used on carbon steel. If you do use a old wire brush make sure you passivate the weld with the stainless cleaner. This will keep the rust from getting bad around the weld. But 400 series of stainless will probably rust anyway. Just make sure you use a good cleaner.

[SupergasDil]

If you spent all that money on a nice stainless system why not weld it right with a TIG and stainless rod ?

[poison heart]

Stainless welds way better than mild steel with a mig. It's a lot cleaner and you can weld it a lot slower and make it look a lot better than regular steel. Of course TIG would be nicer but MIG does look nice too if you're a decent welder

I bought some 3" 45 degree bends from Summit and stainless was the cheapest so I got them, I cut them on 22 degree angles and turned them around and made 2 more 45s and welded them back together. They looked awesome and I'm not even a very experienced welder

[ponchbro]

Originally Posted by poison heart

Stainless welds way better than mild steel with a mig. It's a lot cleaner and you can weld it a lot slower and make it look a lot better than regular steel. Of course TIG would be nicer but MIG does look nice too if you're a decent welder

I bought some 3" 45 degree bends from Summit and stainless was the cheapest so I got them, I cut them on 22 degree angles and turned them around and made 2 more 45s and welded them back together. They looked awesome and I'm not even a very experienced welder

Did you use stainless wire or mold steel?

[jlwdvm]

The thing is that I have a Lincoln 220V MIG welder and the Pypes system is only available in the stainless. I will only have access to the regular MIG Gas but I heard you can get small spools of stainless welding wire at Home Depot. I would rather weld the system up as opposed to using band clamps. If I don't switch out the gas, is it still worth getting the stainless wire. Options? Thanks.

[Z Code 400]

All we ever did, when welding a good slip-fit joint, is to place a spot weld on each side of the joint. On stainless, we would drill a hole on the outside tube and TiG weld a small, circular bead. I still attach tailpipe tips this way.

There is no need whatsoever for a full-circle weld IF the slip fit is tight. If the slip-fit is sloppy, then a full-circle weld would be better...Robert

[poison heart]

I just used regular copper .23 wire with C25 gas. Welder a lot cleaner than mild steel

[jdw_poncho]

Originally Posted by poison heart

I just used regular copper .23 wire with C25 gas. Welder a lot cleaner than mild steel

It will rust using mild steel wire plus you will get galvanic corrosion. Think dissimilar metals, just like copper and steel water lines. They will leak over time...
Its common praction to use a stainless filler rod when welding steel and stainless not carbon steel wire and stainless base metal. If you use a steel wire it will corrode and the exhaust heat will make it happen quicker. Usually the weld cracks around the edge of the stainless. If the fit is tight and it doesn take much stress the weld could last a long time. Put any stress on it with high heat it will crack. Do it right the first time.

[jdw_poncho]

Originally Posted by jlwdvm

The thing is that I have a Lincoln 220V MIG welder and the Pypes system is only available in the stainless. I will only have access to the regular MIG Gas but I heard you can get small spools of stainless welding wire at Home Depot. I would rather weld the system up as opposed to using band clamps. If I don't switch out the gas, is it still worth getting the stainless wire. Options? Thanks.

Buy the stainless wire and try the gas mixture you have. It will work but the weld wont be as pretty and you'll need to mechanically polish or by a brightner that I talked about in a previous post. If spent the money on a SS system why not spend a little more to make sure its welded correctly. If the weld cracks over time you'll have to grind away all of the old weld because it "sugars" and wont give you a good base to weld to again.

Maybe finding someone local to tig weld it for you would be a better solution. If you were closer I could offer the help to you plus let you learn by doing. Maybe ask a VO-Tech school to weld it for you, a lot of good students out there welding.

[PaulatFast]

We have fully welded several dozen stainless Pypes systems with the same welder/wire that is used for sheet metal repair. Welds great. yes the weld will rust. We actually clean the welds and paint with 1500 degree silver paint. Have been doing this since they switched to all stainless several years ago.

[jlwdvm]

Sounds like it will be easier and better to just use band clamps.
Thanks for all the input.

[PaulatFast]

Originally Posted by jlwdvm

Sounds like it will be easier and better to just use band clamps.
Thanks for all the input.

?????????????Doesn't get much easier than turning your welder on and welding.

[jlwdvm]

Just confused on will the Mig and steel wire work, should I use stainless wire, does it matter, will the welds last, etc. After a while all the posts seem to contradict themselves. Just want to do what I can do myself that will look the best and last.

[poison heart]

You can use copper and it will work just fine. I guess it will corrode over time but so will mild steel. I didn't know they made stainless wire. I welded those 45s at least a year and a half ago and it doesn't have any flash rust yet.

Just use stainless wire and C25 gas