Tuning gas output for TIG'ing stainless

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This is a question for those of you who tig stainless, especially thinner stainless with some regularity.I seem to have some inconsistency in my stainless tig welds.  This is especially confounding because I'm using essentially the same setup, last week I welded some 14 ga pipe to a 3/8" plate and it came out beautifully (at least the color and consistency was nice, my weld could definitely be more consistent).  No polishing afterwards, that is what is pictured below.I'm using the same machine, same tungsten, same torch, gas lens, same bottle of argonMachine is a L-Tec Heliarc 307i AC/DC, set to DC.  Amps set to 10 (pulse) 120 (normal) pulse is 300 Hz, 50% Pulse width.  5 sec pre-flow 10 sec post-flow.  15 CFH 100% argon as determined by a flowmeter on the regulator.  Running a 17 series water cooled torch with a gas lens #7 ceramic cup.  3/32nd zirconated tungsten sharpened to a point then dulled, 3/32nd 308L filler rod.  Solar flux on the backside of the weld zone for about 3/4".Clean metal, 308SS, I gave it a quick brushing with a stainless wire brush and blew off any loose particles before doing any weldingToday, same settings and everything, tried to butt weld 2 pieces of 14 ga 308 stainless pipe, and I have TONS of little black dots and my weld bead is a dull grey color, the only place I'm getting the straw color is in the HAZ on either side of my weld bead.Is it worthwhile to get one of the flow meters that I can push up against my tig torch?Is it worthwhile to buy a CK Gas saver torch lens?  I've currently got whatever brand lens the LWS had in stock.Is the thinner metal just getting too hot?  If so, what should I be doing differently? Attached Images
Reply:too hot. same settings for 3/8" on 14 ga as 14ga on 14ga? not gunna workbosses stuff:trailblazer 325maxstar 200my stuff:sa 200fronius transpocket 180100 amp Lincoln w/f97 f350 DITKevin
Reply:get yourself a filtered lense setup either stubby kit for a 17 or a standard filter for a 9. the dots have to be inclusions, whether dirt from inside tubes, or pulling flux through from the backside. I really prefer er347 filler.Last edited by sausage450r; 06-30-2014 at 12:35 AM.'14 HTP invertig 221Thermal Arc 201ts'15 HTP 2400'13 Hypertherm Powermax 30Esab 875Esab 251Clark Metal Servicespecializing in stainless steel exhaust systems
Reply:First of all get rid of the zirconiated tungsten. It is not used in DC welding. Get some thoriated, lanthanated or ceriated.As far as the CL gas saver system goes, I have it but finally reverted back to normal gas lenses for various reasons.
Reply:Originally Posted by 92dlxmantoo hot. same settings for 3/8" on 14 ga as 14ga on 14ga? not gunna work