255c questions

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Hi guys, just bought a slightly used 255c lincoln mig. I have trouble tuning it in for sheet metal, well all metals really. I am using 0,023" wire, and argon/co2, 75%, 25%..It seems that the 110 welders and small 220's are easier to use on sheet metal. I haven't been able to get a smooth crisp buzzing sound out of it....any particular setting for sheet metal, typically welding 20/22 gauge or so...
Reply:Make sure your polarity is right? That will drive you nuts if you don't know better.
Reply:dcep, work clamp is negative....too many settings it seems with infinite adj...hard to tune it right...any of you guys find a sweet spot for sheet metal with 0.023" wire and 75/25 gas for 20 gauge or so sheet metal? I can get it to weld "decent," but it seems the smaller welder does a better job with less fuss...any thoughts?
Reply:DanP76I am like you, to many controls with the infitive adjustments. I have a hard time dailing in my MM350P on the thin stuff (sometimes even the thick stuff). I made it a dedicated machine for 045 wire and I use it to weld the thick stuff. Your machine can be tuned in just right but it will take some time. I use my smaller machine for the thin stuff. I have one machine for each size wire. 030 , 035 and 045.  Ill put it this away, you dont buy a ferrari to deliver the mail, do you? so I would not even bother trying to get that machine to run that small of wire. Yes it can run that size but it is impractical.
Reply:Try .030 wire.  Isn't there a chart in the door for speeds and feeds?I agree, the little migs are perfect for their place.Infinite controls are the balls.Set wire speed first.  I think .023 is 5 inches per amp, so if you want to weld with 30 amps, you could start at a wire speed of 150.  Set the other knob to match it.  Get some scrap and weld with one hand, turn the Voltage knob until you get the smoothest arc.  For .030 wire its two inches for one amp.For .035 its 1.6For .045 its one inch = 1 amp, so 250 ipm is 250 amps, give or take.I got this off the miller website.I have a wirematic 250.  Its just like the SP100, but bigger.  I run .030 or .035 in it.For what you are doing, both knobs are going to be waaay to the left.  DavidLast edited by David R; 09-15-2008 at 04:58 PM.Real world weldin.  When I grow up I want to be a tig weldor.