What kind of differences can you expect between TIG welding and stainless steel versus TIG welding mild steel? Not much. You need a little more amperage out of the machine because stainless is just a little tougher and a little denser metal, so you need a little more horsepower to dig down into it.
Of course, you need the correct TIG filler rod so everything is stainless to make it all rust resistant. Before welding it, stainless steel also likes to be bright, shiny and clean – the cleaner the better. Then you need to clamp it down so everything stays flat. Now you’re good to go.
What about the difference between TIG welding stainless and MIG welding stainless? Now that’s a whole different world! With TIG welding, you are running straight argon gas. With a MIG welder, you want to use trimix. That’s argon and CO2 with a little bit of helium thrown into it just to up the temperature a bit. Just like turning up the amps when TIG welding, the helium helps make the weld hotter. MIG welder will still be kind of smoky and dirty, and you’ll have more clean up, but you can weld stainless steel with MIG.
To TIG stainless steel, though, Kevin sets up his Everlast PowerTIG 255EXT TIG welder. It was on AC because he was welding aluminum, so he switches it over to DC. He’s working with 125 thousands steel, so rule of thumb says to set the welder at about 125 amps. He’s going to bump that up to about 135 amps, though, because it is stainless, and because the stainless is clamped to a cold 1″ piece of cold steel. He might even come back and bump it up a little more.
First, though, he puts on his welding safety equipment to see what he gets.
First he tack welds the metal at the beginning of the joint, in the middle, and at the end. Then he welds between the tacks.
Kevin shows the tack welds, then shows the welds between them. Then he flips over the metal to show the other side of the welded stainless steel. You can see the heat affected area but not any indication that the weld dug down in there the way it should.
That’s a strong suggestion that the amperage may still have been a little too cold. Nonetheless, that gives you a basic idea what to do.
Of course, when you’re all done welding the stainless steel, you need to do the finish work to get it ready to go outside in the world so it’ll last a long, long time. There will be a video about that soon.
Kevin is ready to go back to work, but you might want to stick around for another moment to see him deftly handle his material …..