[toejam2889]

I'm a little concerned about the bottom side of the pipe. I'm welding in 5g. I've tried different things but wanted to get opinions if I should feed the filler through the top tack through the keyhole. I've always done it feeding on the outside... Also I like a slight weave on the root pass. Forward and back just doesn't work for me. Does side to side motion on a root cause problems like porosity or rolling silicon under it gets plenty penetration but I know looks can be deceiving.

[Rick_H]

I'm a little concerned about the bottom side of the pipe. I'm welding in 5g. I've tried different things but wanted to get opinions if I should feed the filler through the top tack through the keyhole. I've always done it feeding on the outside... Also I like a slight weave on the root pass. Forward and back just doesn't work for me. Does side to side motion on a root cause problems like porosity or rolling silicon under it gets plenty penetration but I know looks can be deceiving.

I like forward back or walking the cup, I also feed from the outside exclusively. I wouldn't think a small weave would be an issue as long as you're breaking the edged down and feeding enough material.

If your tack is at 6 o'clock feather it with a grinder if you can.

5g is by far the hardest position

[Coldman]

If you like to wiggle the root on 4" pipe, having a gap slightly wider than the wire so you can lay the wire just inside the pipe works great. This method works for me (gives nice smooth internal reinforcement with ER70S-4 wire) but I always go for knife edge or max. 1mm land.
If you run hot enough, you won't have silicon issues.

[toejam2889]

I agree with 5g being the hardest. Generally I run the root at 115 amps just because of the thick land. 4 inch is a little smaller than what I'm used too. That's the thing about welding almost everyday is something different.