Posted: 7/18/2026 3:54:25 PM EDT
| I have an extra MIG machine sitting in the corner, and that got me wondering. I have had the "opportunity" to weld some really nasty old stainless, such as very old exhaust manifolds and heat shields- things that could never be clean. Can SS MIG power through the crap like it can on mild steel? |
9 lives - 9 pellets... Coincidence?
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What kinds of projects are you looking to do? Stainless MIG takes a special gas blend to do properly. The most recommended mix has a lot of helium in it. When I asked my local welding shop about getting some, they weren't willing to get it for me as an individual without a company account. |
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Expect porosity and cracking in the welds, and embrittlement. Expect Carbon cross-contamination that depletes the chromium in the stainless steel and in time, rust in the weld and heat affected zone. If you TIG weld contaminated stainless, expect tungsten contamination, making it impossible to lay a clean or consistent bead. Bubba can MIG weld you an exhaust, but if it has to look good, or last, you need clean metal and a TIG machine. |
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There is a stainless flux core mig wire available, but I've never run it. I ran just regular stainless wire with C25 gas, it held, but as far as being really stainless and pretty, it was not. It was on some stainless carts that had cracked welds from age and use. From the looks of the original welds, it was probably all tig. Fast forward 10 years, they needed repair again, I bought 1/16 stainless welding rods for stick welding. Ran them on my little Esab Dc inverter at low amps. For that application, it actually looked better than the mig with the wrong gas. |