Need help setting up welder.

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Hi, i just recently purchased a new lincoln 255 mig.Im welding 3" stainless exhaust pipe, Im using a 0.023 stainess wire, and apporpriate gas, the gas is set at 25psi. The tips im using are for 0.030 wire. Now, in the past i have used my old welder to weld mild steel flawless, it was a old esab 200 unit. I had been using it for years ever since i started to weld (its my dads machine)Now, with the new machine, set up with 0.035 wire, welding mild steel with a different gas, it works great.When i switch to stainless, as soon as i pull the trigger, the wire hits the piece and melts away usually sticking to the tip, this gets really annoying and makes it hard to weld.When i do get it started (have to start it furthur away and move in once its going) It appears to be almost dripping off, and it isnt smooth, its really bouncing around on me.Now, my question is, i know this is a big machine for such a small wire, but could my oversized tips be the problem? The wire does slop around a considerable amount. Normally when i weld thin walled pipe, i usually do a series of short welds to keep the heat down, but its not working out for me too well at this point.Ill give it another try tommorow.So is my problem the tips, or do i have the welder set up entierly wrong for stainless, is my wire speed too fast/slow, and as well for the voltage.Im sorry if this is in the wrong section, mods feel free to move it accordinglyTYIA ALL!
Reply:just for laffs try turning down the wire speed and up the amperage by the "same" amount..bouncing off is a sign of too much wire and not enough heatsorta like too much clutch and not enough gas ...zap!
Reply:So you dont feel that using the 0.030 tips with 0.023 wire is having any effect?
Reply:Whoa, missed the part about the tips.  That is definately you're problem.  You're not making a good electrical connection between the gun and the wire, therefore, your arc is intermittent and the wire doesn't melt in time.
Reply:and what about your feed rolls ?if there for .035 than .o23 is going to slip and not feed rightChuckASME Pressure Vessel welder
Reply:Hamiltonrex,I have to agree that the .023 wire is not going to work properly with an .035 tip.Also, just curious, what in your mind is "the appropriate gas" for your stainless MIG welding?  I do pulsed spray transfer of stainless and use either 98/2 Ar/O2 or 95/5 Ar/CO2.  I know some people use a tri-mix with similar O2 or CO2 contents plus some Helium for added heat when short arc welding.Also, you specified that you set the gas at 25 psi.  This means nothing to me.     I am familiar with using a flow meter that reads in cubic feet per hour (CFH) and generally use about 35 CFH for steel and stainless MIG.
Reply:pulser how do you like the puls spray transfer? i run spray transfer to well now its wen i canChuckASME Pressure Vessel welder