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gmaw 4g
Posted: Fri Mar 16, 2012 2:38 pm
by welder in training
So I'm in school for combination welding. Right now I'm working on 4g open root. I have no problem penitrating to get flush on the back side of the workpiece but my instructor insists that I have atleast 1/16" build up on the back. I have no idea how to achieve this. I've been running slower, colder, hotter, faster. Is it all in the work angle? Please help. Voltage is at 16.3, wfs is at 150 and I'm running a big 1/32" open root gap. By the way, my 1, 2, and 3g all penetrated to flush but no build up also.
Re: gmaw 4g
Posted: Fri Mar 16, 2012 10:39 pm
by weldin mike 27
Hi there,
I think as long as your penno is fully fused and not "sucked back" you are going well. 1/16 seems like a lot of build up in an over head weld. Jody recently made a video on this weld. on this site. Oh, if an instructor gives you a task that seems hard, hand them the shield and ask them to show you. If you're gunna talk the talk, you have to be able to walk the walk.
Mick
Re: gmaw 4g
Posted: Mon Mar 19, 2012 1:50 pm
by welder in training
Thanx for the input. After carefull examination of the weld, I did notice a bit of suck-back but just a hair. Any tips for just a bit more penotration? By the way, I did ask him to show me how to do it and he did get about 1/32". The problem is, his tip of staying to one side of the gap and letting it blow back into the gap isn't helping me much. Maybe its just lack of experience on my part. I don't know.
Re: gmaw 4g
Posted: Mon Mar 19, 2012 3:15 pm
by weldin mike 27
Hi there,
Sorry. Ive got no tips as i dont do this type of weldinOn tghe experience side you you do things long enough, you do little things without even thinking about and they can be hard to explain. Maybe try dragging the gun so that the metal is being forced backwards. Only a slight angle of about 30°.
might help.
Mick
Re: gmaw 4g
Posted: Tue Mar 20, 2012 10:49 am
by welder in training
Thanx for the tip. I actually gave that a try last night with a circular pattern and it seemed to work. Part of my problem was I was running a tight weave pattern. Thanx again. I'm sure I will be back on here with some more questions soon...going to 6g pipe.
Re: gmaw 4g
Posted: Tue Mar 20, 2012 3:16 pm
by weldin mike 27
My pleasure. Cant help with 6g. never welded pipe.
Mick.
Re: gmaw 4g
Posted: Thu Mar 22, 2012 6:39 am
by weldin mike 27
Hey there,
Not sure if you have seen this video, Jody made it about a month ago or so. He explains it pretty well.
http://www.youtube.com/watch?v=uWv26K8r ... AAAAAAAAAA
Look at his root pass. Thats about as good as it gets. If Jody cant get 1/16 penno, then no one can.
Mick