Push or Pull

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What technique is better for thin mild steel, .060.Set up is Lincoln Sp-125 with 84/16 argon mix, Adjusted Voltage,wire speed,gas amount.My welds look very good, comparing them to other peoples work.
Reply:Generally speaking (disclaimer, your technique may vary according to weld results)MIG with gas = pushFlux Core MIG = pullDon't worry so much about exact technique, just make sure the welds are good.  Pull with the flux core wire is due to flux core's ability to penetrate deeper.  On thin sheet metal you may not want to use flux core.  In this case where you are using gas, you can use either.  Pull will allow less penetration, push will keep the bead covered in gas better.  Pull with gas, you just slow down a bit & reduce the heat slightly.  I've done both techniques & obtained acceptable (to me) welds.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Pulling (backhand) increases penetration and narrows the bead, also increases the bead height.  Pushing widens and flattens the bead and gives less penetration.   Use push on thin metal with solid wire and gas.Pull with fluxcore.Another way to reduce blow through is turn the sheetmetal up on edge and weld it vertical-down.Your gas mix works fine, no need to change to 75/25.Last edited by DesertRider33; 08-16-2009 at 02:46 PM.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:ill,DR33 is on the money with his advice.Reason being, when pulling a bead, the wire is directed at an already molten puddle, thereby increasing penetration.  When pushing, the wire is directed at material that has yet to be melted, therefore less penetration.Fluxcore wire is generally pulled due to the slag created by the fluxcore wire.  Old expression (if there's slag, you drag).  Fluxcore, by it's nature, gives more penetration than solid wire with gas, which makes it less attractive for use with thin metal.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:Originally Posted by SundownIIIill,DR33 is on the money with his advice.Reason being, when pulling a bead, the wire is directed at an already molten puddle, thereby increasing penetration.  When pushing, the wire is directed at material that has yet to be melted, therefore less penetration.Fluxcore wire is generally pulled due to the slag created by the fluxcore wire.  Old expression (if there's slag, you drag).  Fluxcore, by it's nature, gives more penetration than solid wire with gas, which makes it less attractive for use with thin metal.