Welding Tips and Tricks

I'm welding with .035 L-56 wire with a CO2 shielding gas. The material is a 6 inch schedule 40 pipe.
I got the root an the fill figured out but when I go to weld the stringer cap it gets all ropey. I've tryed turning down the wire feed speed an osalating slightly but it still Ropes up. If anyone has any advice it would be greatly appreciated.

I think I'd turn UP the wire, or slightly down the voltage, so the Amperage at the weld is higher. "Ropey" sounds like it's quenching too quickly. The weld is "full", and the heat has lots of places to flow to. You can increase the effective amperage by either increasing wire speed or reducing voltage.

Now that I've thought through what I said, my suggestion, without "seeing" what's going on, would be to increase voltage a little, and wire speed a little more, and see what happens.

Take this for what it's worth... I've done MIG root on pipe. Not MIG all the way. It's my thoughts on how MIG behaves in general. Your mileage may vary.

Steve S

Hey,

I imagine that the prep on the pipe is not very wide? I have found that when you have a small prep, as in no that thick of metal (so not requiring a large prep) the weld pool stays doesnt have enough surface tension to hold the metal nice and flat, so it all falls in to the middle. Is it possible to do two stringer beads as a cap instead of the one slightly weave? Root and fill as needed the one stringer towards one side of the prep then another to fill the other edge???? This would reduce the size of the puddle and therefore the amount it sags. This method would require no sideways movement of the wire on the stringers, only a little flick up then down and pause for a half a second, with just a slight angle towards the side you are filling. (please take this info with a grain of salt, I do LOTS of mig but not pipe. So info may be complete crap.

Mick