welding with gas

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i have a hf welder and i am welding with .030 mig wire and carbon dioxide gas the welds dont look bad but their not digging as mush as the flux and its kinda jumping not smooth any one know what wrong.1st pic is flux like crap 2nd mig with gas some are good but way high build the best ones are push pull the rest are O and W style.sorry about the pics camera phone
Reply:Did you change the polarity on the machine going from FCAW to GMAW
Reply:Flux-core wire burns hotter, and will penetrate deeper, than solid wire with shielding gas. When I went from flux to solid wire and CO2 on my Lincoln, I had to turn the welder up more (per its chart) to do the same thickness as I did with flux-core. It did seem to me that the arc became less stable with gas. But maybe I could just see the arc better. The sound of the arc also seemed to change. Sometimes the arc is smooth. And other times it seems less stable, with more spatter. It seems to me that this may happen when I slow down too much, and the puddle gets larger, under the wire. Maybe the drops of wire are landing in a big pool of molten steel, and splattering, I don't know for sure. Make sure you changed your polarity, as piledrivin suggested. I've read that you should push when using gas, and pull when using flux-core. What amperage is the welder, and how thick is the metal you're welding? The guideline I've seen is you need 1 amp per 0.001" of steel thickness, with gas. So if it was 1/8" steel, you'd need around 125 amps.
Reply:i did switch polarity befor starting it is on gmaw my welder is 140 amp 220 volt and it is 1/8" steel i was thinking this might be pickled in oil the suppler didnt day if it was hot or cold rolled i will try push next.
Reply:well after watching some youtube videos i have some thoughts 1 when i went from flux to mig i should have blown the liner out2 my wire feed maybe alittle slow 3 just wire brushing the steel didnt get it clean for mig
Reply:First picture, beads on the right. all look like the wrong polarity.flux core in negative and gas is positive on the wire.If the bead just won't flow out right, Try switching to 75/25 gas.I have seen a small welder that just would not weld at all with co2.with 75/25 it welded great.So don't give up, try a few different things
Reply:Wire brushing really doesn't do anything for steel unless it's super heavy rust. All it does is polish the rust or mill scale. To get decent prep, you need to grind or sand to a silver finish with bare steel.The mig with gas beads show some promise. You  probably need to have that machine set to max voltage to do 14 ga to 1/8" and set your wire speed roughly between 50-75%. Your machine in many ways will handicap you. If it's the HF machine, erratic feeding is fairly typical and you are fairly limited on your output power. You probably also need to slow down just a bit from what I see in those picts. Beads on flat plate will always look a bit "tall" compared to beads used for joints..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:agree with ccawgc.  Try switching to a 75/25 mix or even a trimix with some helium.  That will help penetration.
Reply:agree with ccawgc.  Try switching to a 75/25 mix or even a trimix with some helium.  That will help penetration.  Also push the bead while MIG welding instead of dragging like flux cored
Reply:ya the hf welder is great with flux but i will start saving for a miller, lincoln, or hobart or just do everything with flux and ugly
Reply:Get someone who knows what they are doing to help you set the welder and give you some helpPushing instead of pulling and using a trimix gas will not help anymore than crossing your fingers whilst standing on one leg will
Reply:Originally Posted by empireweldingagree with ccawgc.  Try switching to a 75/25 mix or even a trimix with some helium.  That will help penetration.
Reply:1. When mig welding if the steel has to be clean to chrome look if you are using weldable primer will it weld right.2. How long can a tank of CO2 site befor you cant use it if you have to change it at all.3. CO2 mig welding do you get some flames out of the tip sometime when welding or is the CO2 bad.