help with mig welding?

i do custome exhaust anf the pipe is only maybe a 16 of an inch thick. i dont do circular beads (altho i can) i weld from pipe to pipe like a sewing needle. lol. i am a decent welder but my weld always puddles over the lap joint because its hard to keep a bead that thin. any tips?

3 Answers

  • 8 years ago
    Favorite Answer

    If your machine has a pulse feature, learn how to use it.

    Other than that, use the smallest diameter solid wire you can find with appropriate liner, drive wheels, and contact tip. Use a 75%/25% gas blend. Weld in the 5G vertical down position unless you have the means to accomplish 1G. Turn you machines settings down. Try 16 volts and 250 for the wire speed as a baseline and adjusts from there. If there comes a time when you are about to loose the puddle, you can lengthen your stick out to decrease the voltage until you get it back under control.

    Source(s): ASME Certified Pipe Welder
  • If you're welding the tubing, is it really necessary to use lap joints? Use butt joints if possible..

    "Puddles over" doesn't really tell me anything. Are you talking about "overlap"?

    What shield gas are you using? what size wire? What parameters do you typically use for this?

    ----->I suspect you're either welding too hot, or too fast.

    Although 1/16" is on the thinner side that's "bread-and-butter" for MIG welding. I'm surprised you're having problems. When you start getting down to 18 gauge, that's what I personally would consider "thin."

    Reduce your wire feed speed, then fine-tune your voltage until you get a nice crackling sound. Then slow down and let the puddle develop on it's own rather than trying to "force" the weld.

    You may also have fit-up issues. With thin stuff, getting EXACT fit-up becomes ever more important

    Working with thin materials really magnifies the problem of filling gaps. It's almost impossible to fill a gap larger than the material itself. So if you have bigger than a 1/16" gap, take the thing apart and make it fit better.

  • 4 years ago

    pondering you're in all threat going to apply chromoly tubing, i think of MIG is a thank you to pass. At any fee, inverter-based MIG setups are much less severe priced adequate that stick welding is all yet out of date. Stick welding purely seems for use the place the welder has to paintings upside-down.

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