MIG welding 16ga Stainless? Pulsed?

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OK, so at my real job, we're going to go from spot welding to seam welding a bunch of our standard products (It boils down to, they're 16ga 304 and 316 boxes). If we do this, we'll end up hiring another welder (we just have one dedicated welder, right now), and buying another welding machine. We currently have a MM250 and a Syncrowave 250.Some of it will be ground into outside radius corners, and some of it will be left as-is. The welds need to look good, but they also need to be as fast as possible. The obvious thing would be to buy a Dynasty, but TIG welding is slow. Can pulsed-MIG (with a MM350, for instance) be done without warping the material all to hell? If so, stainless wire can be fed with the standard gun, right? Or do we need a push-pull gun? Thanks,Mike
Reply:Yes to both questions and no to push pull unless you have an extremely long hose run from machine to workstationPulsed mig has the ability to offer fine heat control, and was developed for production sheet steel  welding.Don't forget operator skill in the mix, as this has as much to do with weld quality as  any of the other variables.Spending money on someone who is overqualified will save you money in rejects, problem solving ,setup of machine and changes to setup as production changes.Last edited by safetyfirstintexas; 07-11-2012 at 12:01 PM.Reason: more
Reply:It also might be beneficial to build some copper (or water cooled) cooling blocks for production of your products.Welding/Fab Pics: www.UtahWeld.com
Reply:Using pulsed on 16 Ga stainless.....I fail to understand why you believe stainless cannot be welded with short-circuit just like you would use for 16 gage carbon steel. Let me guess, you went over to your LWS and asked the salesman for advice. It's almost a given that's he's going to tell you you need new equipment that's going to cost you $7,000Concern #1 is minimizing heat input, especially on outside corners.Concern #2 is controlling weld oxidation especially for 316, Excessive oxidation = loss of chromium content = corrosion problems down the road.Although pulsed generally produces less heat input than CV spray, it still produces a lot more than short circuit does.
Reply:Originally Posted by JoshfromsaltlakeUsing pulsed on 16 Ga stainless.....I fail to understand why you believe stainless cannot be welded with short-circuit just like you would use for 16 gage carbon steel. Let me guess, you went over to your LWS and asked the salesman for advice. It's almost a given that's he's going to tell you you need new equipment that's going to cost you $7,000Concern #1 is minimizing heat input, especially on outside corners.Concern #2 is controlling weld oxidation especially for 316, Excessive oxidation = loss of chromium content = corrosion problems down the road.Although pulsed generally produces less heat input than CV spray, it still produces a lot more than short circuit does.
Reply:The only stainless pulsed mig that ever worked for me was with my Millermatic 200 with pulse module and spoolgun using .023 308L. Even then kinking was common. Using Trimix, the welds still had a black surface to it that was not a problem as they were outside corner welds that got ground down. The pulse was a slow speed pulse that was just an on/off sequence to the whole weld. Due to the grinding which I gave up, I don't do that work anymore, or likely will never do again. I can not think modern equipment with push/pull or spoolgun, and high speed pulse could do any better. But Ed Craig's StainlessMix, 98%argon/2%co2 may work. But .023 wire is a must, and a very steady hand.Perhaps any tig with high speed pulse(100pps minimum) is your answer.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:can't tell you anything about pulsed mig... but I can tell you Tig with a good operator can be a lot faster then you think, now a good operator may cost more then the equipment and is a lot harder to find.anyway there's more to it then just welding, you should consider spatter cleanup, surface finishing and other things when choosing the process for a production run.--------------------------------------------------------------www.becmotors.nlyup, I quit welding.. joined welder anonymous
Reply:Originally Posted by barton174I know it can be welded with SC, but SC doesn't look like TIG welding, and from what I've read, pulsed is much closer. I did not go into IOC/LWS/SG for advice. I came here, where it's not peoples' jobs to sell me stuff. This is why I'm asking about the process, not asking which pulse-capable welder I should have the company buy.I was under the impression that the point of pulsed MIG was to put down enough heat to penetrate (in pulses), but to put less total heat into the material than SC?Mike
Reply:Originally Posted by barton174I know it can be welded with SC, but SC doesn't look like TIG welding, and from what I've read, pulsed is much closer. I did not go into IOC/LWS/SG for advice. I came here, where it's not peoples' jobs to sell me stuff. This is why I'm asking about the process, not asking which pulse-capable welder I should have the company buy.I was under the impression that the point of pulsed MIG was to put down enough heat to penetrate (in pulses), but to put less total heat into the material than SC?
Reply:Originally Posted by SupeThe only pulsed GMAW that will resemble GTAW is the pulse on pulse modes which are used with aluminum.  Pulsed GMAW power supplies on steel won't look any different than traditional spray.
Reply:Whatever you decide, show us some pics!-AaronJet 17.5" Drill Press1942 South Bend 16x84 Lathe1980s Miller 320A / BP --- 2013 Power Mig 2562012 Jet 7x12 Horizontal BandsawVictor O/A Setup
Reply:The lincoln powerwave 350 might be able yo do all of the above with the optional stt feature. I have welded aluminum on the machine and it is incredible, and I have talked to a stainless welder who used to use one he said he could do perfect 1/16" welds with no spatter. Might be worth looking in to.