Some ??'s about tigging SS pipe/tube welding...

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So I have been working on tigging 5g and 6g( 4'' inch tube, 1/2'' wall ). I have it down really good, the root, fill, and cap all are excellent and consistant on mild steel. However I want to do something more challenging like SS but the problem is my welding class doesn't have any available... So I have been trying to use 308/309 SS rod on mild steel and I'm wondering if I'm waisting my time doing this. Does it even compare to welding real SS??  I use a Lincoln Precision Tig 275, 150-80 amps with peddle, 1/16th 308/309 filler, no pulse allthough I have tried pulsing the peddle, 3/32 thoriated tungsten, #7 gas lens. 30- 40 cf on argon. I get a little bit of color in the center of the weld but the toes are gray.Lincoln pro mig 180Lincoln Square Wave Tig 300/wp 20/home built water cooler Victor, Purox, Harris, O/A welding/cutting setupsVintage Craftsman drill pressVintage Craftsman/Atlas 12"x 36'' lathe7''x 12'' w/c band saw Everlast 140 st
Reply:It's a whole different world with stainless material compared to mild steel. The best thing you need to do is get a hold of stainless somehow. Maybe ask your instructor what you can do to get your hands on some. One thing to remember is that heat is the biggest factor when welding stainless. You wouldn't weld the same amperage on mild steel as you would stainless.Miller Dynasty 200Millermatic 211Instagram?.... find me @ WELD_MEDIC
Reply:Thanks for the reply tig... my instructor has a hard enough time getting M/S plate or tube let alone S/S..he has one company that donates M/S tube every couple of years, but with the high price for scrap its now allmost impossible.. I have been practicing on welding scraps of S/S sheet (16g and 3/16)...Lincoln pro mig 180Lincoln Square Wave Tig 300/wp 20/home built water cooler Victor, Purox, Harris, O/A welding/cutting setupsVintage Craftsman drill pressVintage Craftsman/Atlas 12"x 36'' lathe7''x 12'' w/c band saw Everlast 140 st
Reply:Go ahead and practice all you can on the mild stock, so much easier to prep.  It's used all the time with 309 wire.... including on actual tests.  Maybe later you can get some actual ss stock.  You don't mention purging.  If not, do a search.