Mig Weld Stainless Steel??

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Ok Guys,I'm sure I will suffer for this question. Is there a mig set up to weld stainless steel. I've been fabricating many years but have never seen or had the need to mig stainless. I'm currently bidding a few jobs using 14ga. to 11ga. SS sheet and 1/2"dia. to 1"dia SS round stock. The jobs will require yards and yards of SS welds. Mostly 4" runs and less. Currently I tig most of the SS I do, occasionally stick weld the thicker stuff in field.Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180
Reply:I have run stainless through my mm175. It even has a chart for it. I bought it from a shop that bought it for one job. Clean up on sanitary stainless sucks but it worksMillermatic 252millermatic 175miller 300 Thunderboltlincoln ranger 250smith torcheslots of bfh'sIf it dont fit get a bigger hammer
Reply:Don't expect SS mig welds to look anything like tig. The welds will most likely be smooth rather than the stack of dimes look and be gray in color.Tbone had a recent thread with questions on SS mig, and it's been covered here several times in other threads as well.www.weldingweb.com/vbb/showthread.php?t=72981.No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:The guage-thickness stuff, sure.  Usually use short-circuit transfer mode with tri-mix (helium-argon-CO2).  My small Lincolns can do it OK.  The puddle seems more sluggish than GMAW on plain steel.The thicker pieces?  That's really the realm of spray-mode transfer IMHO.  For that, you need a 'big' machine that can do spray-transfer.  Which usually means the 250-class machine or better/bigger.Pay attention to getting the 'correct' filler alloy for the parent material alloy.  Different stainless alloys use different filler alloys.  Some of the alloys (parent and thus the filler) are rather 'special'.Plain-old 304 alloy parent is welded with 308 filler.  If the parent alloy is something else, check for the recommended filler alloy and then double-check the filler pricing/availablity and any 'special' procedures needed.  The best laid schemes ... Gang oft agley ...
Reply:I'm running a MM 252. I have 75/25 gas and 98/2 gas. The parent metal is to be 1/4", 309 stainless steel plate and 1/4", 330 stainless steel. I could tig or stick with ease but hope I set up  a mig procedure to save labor.Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180
Reply:For that material you can go one of two ways.Short circuit with tri-mix (90%Helium/7.5%Argon/2.5%CO2) (Ed Craig swears by a 98%Argon/2%CO2 mix but I haven't used this).  I know the tri-mix yields a good and corrosion resistant weld.If you can keep the material "in-position" I'd recommend a spray transfer with an Argon rich mix (95-98%Argon, balance CO2).  This will yield a better, faster weld.  Only problem is the puddle will be very fluid and difficult to hold out of postion.Personally, I'd use pulsed spray with a 98%Argon/2%CO2 mix.  All the advantages of spray, but the pulse allows for out of position welding.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:I second Sundown's gas recommendations. 309L for filler metal. 1/4" plate is a mite heavy for short-arc- if you can't use spray, stick might be your best option.JohnA few weldersA lot of hammersA whole lot of C-clamps
Reply:Is 309 still the prefered filler for 330 to 309 welding?Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX
Reply:McKay's suggested chart on stainless does indeed list 309 (or 312 first) for welding 330 and 309 together.  A bit surprising to me, given that 330 has ~2x the nickel as 309 (34-37% for 330 versus 12-15% for 309, chromium levels are closer at 17-20% for 330 and 22-24% for 309).330 to 330 is supposed to use 330 though.I'd double-check with the customer on end-product usage and if they require full-up 330 for the usage of the product (high-heat item?).  If so, I don't see any 330 wire with a quick check of the 'usual' suspects, but 330 SMAW sticks are listed/referenced (whether you can actually get them is another question though, eh?)  The best laid schemes ... Gang oft agley ...
Reply:Originally Posted by SundownIIIIf you can keep the material "in-position" I'd recommend a spray transfer with an Argon rich mix (95-98%Argon, balance CO2).  This will yield a better, faster weld.  Only problem is the puddle will be very fluid and difficult to hold out of postion.Personally, I'd use pulsed spray with a 98%Argon/2%CO2 mix.  All the advantages of spray, but the pulse allows for out of position welding.