Mig Gases

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I was wondering how many of you use co2 or argon co2 mix when using mig on mild steel.  I have used co2 for 20 years and just started using argon co2 mix and I am having a lot of inclusions on mild steel with a millermatic 251 on mild steel 1/4" thick.
Reply:I run a Hobart 140 mig in my shop on co2 argon and am pretty happy with it. I like it because I switch wire and am off to the races with stainless steel restaurant equipment without a need to change gases. I never have had much trouble with it in either stainless or mild steel.
Reply:I use a Lincoln Pro-MIG 180 and have always used argon/CO2 and have no problems other than my self-inflicted technique problems. I have run the argon/CO2 at higher and lower pressures (to the gun) and really had little difference within reasonable limits as called for by Lincoln for this machine.Tom Hintz, publisherwww.newmetalworker.comLincoln Pro Mig 180Lincoln AC 255Determination
Reply:Never had any issues with either 75/25 or 92/8 running solid wire. Not sure what mix my buddy is running exactly, other than it's not 100% CO2, and he does xray quality mig welds every day with no issues either.Not sure why you are having issues, assuming you are not loosing the shielding gas due to wind etc. Picts would help..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:Good point DSW. Could your gas flow be off or perhaps a bad batch of argon?Regards,RobGreat Basin WeldingInstagramBlue weldersRed weldersMy luscious Table DIY TIG Torch cooler
Reply:I agree that pics and settings are needed for much help.If your used to Co2 and moving to mix, cleaning could be an issue. Otherwise if your settings are correct you should be seeing cleaner more attractive looking beads.Matt
Reply:By inclusion, I suspect you mean solidified bubbles in the bead.There is a slight possibility that there is not enough heat.  On the 251 trust the panel inside the cover as your starting point.  The 251 has a very flat voltage curve an as a result you will find the 251 runs hotter than other welders you might be used to.  Follow the chart or drop 1V vs. what other welders need.   ER70-6 wire, .035 with C25.  Lincoln's wire seems to work pretty good.  According to the chart on the door that should cover from about 22gauge (hah!) to 1/2".  With a clean nozzle, I've run as high as 25cfh (victor flow meter).Most of the time when I see inclusions its from out running the shielding gas.  Never had that issue with the M10 though.  The Bernard gun with the fine tips is more of an issue.Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX