GMAW-Pulse, or Pulsing with Frustration

Howdy, All! Anyone have any good rules of thumb to follow for pulsed mig? I've got to requalify on it. It's one of those qualifications (quals) that I got several years ago and never once used.

Here's the details:

Position- Vertical Plate- 1/2" OS (ordenary steel) Lincoln LN-25 with Lincoln power supply,

I'm running at 130 ipm wire speed, 19.0 volts, 105 pulses.

I can turn out a perfect root and a perfect second layer (root flat, perfectly blended toes, no undercut, full penitration visible on backside with no bulges or goobers.

Putting on a cover pass is killing me. We've got a chart giving us a minimum travel speed for controlling our heat input, so I've got to travel up the plate at least 3 inches a minute. I keep violating our max reinforcement of 3/16" as-welded though. I try to travel faster, and I start getting sloppy with my weave or I undercut the plate on half of my weave's toes.

Any tips would be appreciated!

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OK, I turned in my vertical plate day before yesterday. Now I'm working on overhead, and it's a real pain in the neck. Literally! Used to be I'd just let my head hang backwards, putting my hood about 8 inches from the mig gun, and weld 'er up. After C4-5-6 fusions though, I'm having a hard time looking up long enough to run a 6 in test plate.

So far, my overhead welds are looking good, when I can get a good root in. Anyone know if gmaw-pulse is subject to arc-blow in the overhead position? It seems like it is, at least with the root pass. The arc wants to stick to one side of the joint rather than smoothly filling it up from the center out. Holding both arms up while looking up and using a smooth motion is hard enough- I really don't like having to take the time a concentrate on a weave, too!

I also wish pulse penetrated better. Every once in a while the wire will ball up then spit into the weld, making me nervous for lack of fusion. Do I need to be worried about that, or is the occasional droplet ok?

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Ok, all my pulse plates are turned in. Now it's waiting for results on all my plates (stick, dual-shield, tig 100s-1, mig-pulse and spray) that'll kill me. Did I drop any? Hope I'll find out next week.

I would love for the shipyard to keep me in the weld school so I can get my pipe qualifications back. That'll net me most of the material types again, too.

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