welding 304 stainless tanks

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Im currently welding up some stainless 30k tanks. Now I've welded my far share of stainless   mainly tig. But we are welding these tanks with 308 hard wire. And the welds are turning out like crap.. not just mine haha... now the material is 3/16" butt joint small v groove. Running the welder around 21 to 23 volts wire speed 3 anhalf ish. The position is horizontal. My question is what do you guys recommend we try?
Reply:Horizontal? why not flat?Are you using an appropriate gas and flow setting?Welding/Fab Pics: www.UtahWeld.com
Reply:try pushing the arc, keep the shielding gas out in front of the puddle.     Also pics would help,  as your never going to get TIG quality weld with a mig machine on stainless.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:I'll try to upload some pics in the morning. We are installing the tank in 5 foot sections out side with a crane. So we are unable to weld flate. I've tried pushing and dragging. We are using a trimix sheilding gas ran at about 20lb.
Reply:Here are the pics
Reply:I'm no expert but by the way it's sagging I'd say it's too hot, or you need to try whipping it. or switch to flux core wire.what are they going to put in that tank?Last edited by TimmyTIG; 12-28-2012 at 05:49 PM.
Reply:The funny thing is that we are whipping the puddle. It indeed may be to hot for 0.35 wire. The scary part is that everybody at this shop is ok with this. I found a roll of flux core stainless today so ill try that on the next tank. The tanks are holding deicer for an airport
Reply:you might have to run two small, quick beads instead of one big one.
Reply:that dosent look like much of a whip to me.  try more back and forth motion in line with the weldVantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:I know it looks like i was just pushing it but i was ocalating just to get that ugly thing haha.
Reply:Have any of you guys ran stainless dual shield? I was wondering about which gas to use should i stick with the trimix or go back to the 75/25 mix? Thanks for your guy's input
Reply:I haven't ran any in yeas but I had the best luck with straight argon. When I went to a mix I had issues. With the argon you could slow the wire speed down because the arc would be longer with the argon so your slower travel speed allowed more heat into the base metal with less filler. I was told there was no difference in running straight argon but I have a different opinion.
Reply:SS FCAW usually wants 75/25, sometimes 100% CO2Running ss solid wire on pure argon is going to suckExperience is something you get right after you need it
Reply:Looks hot and to quick, drop the heat a click and the speed a bit. 75/25 would work better.Welding Supervisor Department of Corrections.