newb question-weld stainless to aluminized exhaust?

[thegrobe]

Hi All,
New here but have been reading for a long time, thanks for all I have already learned, but I got a question I need help with.

I am getting ready to fab up the exhaust on my project car. I plan on using aluminized pipe for the majority of the project. I am grinding off the coating for the weld area. I have no problem migging the thin metal, I have done 80% of all of my other welding on sheetmetal. I am running 75/25 on a mig welder .23 wire - all there is good.

The question I have is this: There is a section of stainless I need to attach the pipes to. Can I weld the stainless to the aluminized pipe using my mig and 75/25 mix? Or do I really need to get stainless wire and tri mix? The expense for that is a bit prohibitive for making only two welds.

Will the stainless weld okay to the aluminized using 75/25 or maybe even flux core or am I asking for trouble?

If the only problem will be that the weld will be susceptible to rust, I can live with that. I can use VHT exhaust paint or something else to treat the area. (the welds in the aluminized sections need to be coated anyway)

Thanks for any input

[sg3487]

see if you can get a small spool of 309L ss dual sheild wire. your 75/25 should work ok. some wires will recomend CO2 but for what your doing I don't think you'll have any problems.

[thegrobe]

Thanks sg I will look into that. So that is a stainless wire. So I can run stainless wire and the 75/25 to joint he two with no problems? thanks again

[Portable Welder]

The pipe that yor welding is steel pipe with a coating and your welding it to stainless.

I say just weld it with your ER70-S6 wire.

[sg3487]

309L dual sheild is a flux cored wire that also requires gas sheilding, but portable is probably correct, your er70s should hold fine for what you doing.

[thegrobe]

Many thanks for the replies, I will give it a go.

[con_fuse9]

Before you thank someone, check up on the prices.

ESAB Shield-Bright flux core gas shielded 309 can run $20/lbs....

If you want to buy a 33# roll (not even sure you can buy smaller) its like $600!

What's a TIG welder on Craigslist go for?

[Nitesky]

I found this with Google but is still expensive:
http://store.weldingdepot.com/cgi/we...ml?id=vZ7yjfSy

I would be tempted to weld it with regular MIG wire for mild steel.

[thegrobe]

Looking at those prices, I think i will give it a try with the ER70-S6.... I like the comment about picking up a used TIG welder! Maybe sometime, when I've got the cash....

[jardine]

Don't out think or out spend your self. Weld it with your currant set up and don't worry about it. I wouldn't even worry about grinding off the coating. I don't know what type of SS it is but most likely 409 or 304.