Dual Shield 1G Test

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I really need some tips passing the 1G certification test with dual shield wire.I recently took this test with solid wire and dual shield wire.I passed the solid wire test with no problem.I had a problem with the dual shield wire.  The reasons for failing were a TON of slagin the root and lack of fusion.Here is the details for my test:Lincoln Ultracore 71A75 0.045" wire.75/25 Ar/ CO2 gas27.5 volts, 350 impI did the bevel grove butt joint in 4 passes:1 weaved root ( I have read this is a bad idea)1 stacked stringer2 stringer for the cap ( side by side)The weld its self was beautiful in appearance, so I think I am okay on the settings.The problem is the root.  There is a TON of slag in the x-ray and lack of fusion.I have since tried two passes for the root ( side by side) and gotten almost no slag but still have some problems at the ends of the test plate with lack of fusion on the second root pass.I have heard of grinding out the root, but I'm not sure what this does.  Can anyonegive me some insight on what I may be doing wrong ( gun angle, technique) and maybe give a suggestive welding procedure?  Thanks!
Reply:Hello ehart, you haven't said what the groove specifications are: groove angle? plate thickness( I'm guessing possibly 3/8")? backing or not? whether you are using a forehand or backhand progression? root opening(1/8", 3/16", 1/4")?      Personally, I would try to do the root in one pass using a backhand(drag) progression with a gun angle of about 10 to 15 degrees. I would also try to travel just slowly enough to ensure that I had tied into both sides of the groove. Then I would finish it out in the same manner that you described from the root out to the cap using a single pass filler after the root and then a 2 bead cap. Use a backhand(drag) progression for all of your beads, less likely to trap slag by having it run out in front of the weld pool and become trapped. Also be sure that your plate is oriented either level or slightly uphill to aid with prevention of slag entrapment. My $.02 based on your description. Best regards, AllanLast edited by aevald; 01-03-2012 at 02:44 AM.aevald
Reply:Originally Posted by aevaldHello ehart, you haven't said what the groove specifications are: groove angle? plate thickness( I'm guessing possibly 3/8")? backing or not? whether you are using a forehand or backhand progression? root opening(1/8", 3/16", 1/4")?      Personally, I would try to do the root in one pass using a backhand(drag) progression with a gun angle of about 10 to 15 degrees. I would also try to travel just slowly enough to ensure that I had tied into both sides of the groove. Then I would finish it out in the same manner that you described from the root out to the cap using a single pass filler after the root and then a 2 bead cap. Use a backhand(drag) progression for all of your beads, less likely to trap slag by having it run out in front of the weld pool and become trapped. Also be sure that your plate is oriented either level or slightly uphill to aid with prevention of slag entrapment. My $.02 based on your description. Best regards, Allan
Reply:Yes ehart, I was referring to "forehand", which is commonly referred to as pushing by many. That sort of technique is more likely to cause issues with trapped slag, particularly in the 1G position. Oddly enough, many years ago when I was in welding school my instructors told me that the 1G test(flat) could be the hardest to pass of any of the weld postions. Their point was, that gravity would cause the slag to remain at the root or sides of your weld passes and not readily be forced out, but rather might be bridged over or otherwise trapped. So give the backhand or drag method a go on your practicing and next attempt, I believe you will have a better chance at success. Good luck and regards, Allanaevald
Reply:Drag the **** out of it and there should be no problem... you're almost guaranteed slag inclusion if you don't.Welding/Fab Pics: www.UtahWeld.com
Reply:Thanks for all the help guys.I talked with lincoln electric today and they gaveme almost the exact same advice.  I never knew you mustpull when using shielded wires.The guy I talked with also recommended running the test at 28V and 500 imp.It runs AWESOME.  I can do the test in two passes and it is really good looking.We'll see how my test goes.
Reply:Don't forget to start and stop your beads on the backing plate so that the bead has time to: form before you enter the groove; and maintain through the end of the groove.Do what it takes to get the job done right.