6G pipe cert test - help needed

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On the 13th, I’ll be taking my 6G pipe certification test. 6in pipe; 3/32 gap; 3/32 landing. 3/32” 6010 root; 3/32 – 1/8” 7018 fill/cover. Grinding is allowed. No downhill welding.This is the end of my 2nd semester of pipe welding. I have one more class to try to get this down (on the 6th). Luckily, I should be able to come in early and stay late so I should have plenty of time.I am semi-confident in my root pass (struggling a bit with consistency but the teacher says it is good), I feel good about my hot and intermediate passes, but I am struggling with my cover/final passes for reasons that I can’t quite figure out.My first issue – on my cover pass, I keep getting porosity on the bottom of my pipe, mainly where I start my passes to go up each side of the pipe.Maybe this diagram will help explain it better.After every pass, I hit it with a wirewheel and check for any slag along the edges, which I then use a pick or grinder to get out. I am very confident that this is not a cleaning issue and I don’t have any porosity issues elsewhere on my pipe.For this, I usually run the 1/8'' 7018 at about 115-120 amps. I always strike an arc, long arc away from the pipe to let the rod heat up for a few seconds, and then go to work. My instructor told me to try to start slightly farther ahead of where I want the weld to be, move quickly when overhead until I start to get into vertical position. I have tried to switch up my angle a bit but nothing I’ve tried has helped much. I am guessing that I may be long arc-ing a bit too much at the start of the pass, but its hard to tell.Any ideas or tips?-------My second issue – I believe this will just take more practice, but maybe someone can help. My cover pass seems very sloppy overall. I just can’t seem to get it to do what I want. I guess the main problem is just keeping each stringer neat and uniformed, but mine just looks like garbage to me.I don’t have this issue on flat plate in any postion – only with pipe. So again I ask, any tips or is this really just something that takes more practice? I think I’ll take a piece of scrap pipe and just go around it several times for practice next class as well.
Reply:Are you doing the cap in beads. At our company a 2g and 5g covers you for a 6g
Reply:Originally Posted by jbriggs33I am guessing that I may be long arc-ing a bit too much at the start of the pass.
Reply:Originally Posted by daveymAre you doing the cap in beads. At our company a 2g and 5g covers you for a 6g
Reply:I have been working on taking the same test, using 3/32" 7018 for the cap.  Try the 3/32 might allow you to slow down.
Reply:Don't long arc on your starts with 7018.Never!You will get porosity big time.Just a couple welders, big hammers, grinders, and torches.Work will free you.Men in dirty jeans built this country, while men in clean suits have destroyed it. Trump/Carson 2016-2024
Reply:Originally Posted by AKweldshopDon't long arc on your starts with 7018.Never!You will get porosity big time.
Reply:Originally Posted by AKweldshopDon't long arc on your starts with 7018.Never!You will get porosity big time.
Reply:99.9 % of the time I start the arc 1/2” to 3/4” ahead of the intended start point, (in the weld zone) that way the rod is up to temperature. You should never start the arc outside of the weld zone / path. Especially on a test! You can have a perfectly welded pipe and be busted out for arc marks outside the weld zone. Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:When I was doing 5g caps I struggled to keep bottom weave tight. My arc would of course undercut, but never understood the porosity.
Reply:No mention of wall thickness but if using sch. 40, I'd go with a hot 3/32" filler instead of a cold 1/8".  More percentage to getting clean starts.  If using the 1/8", I'd feather every start to check for porosity.
Reply:You need to switch things up some.1/8 6010 for root.3/32 7018 for cap.Porosity on bottom is probably from running too cold.
Reply:Originally Posted by TimmyTIGYou need to switch things up some.1/8 6010 for root.3/32 7018 for cap.Porosity on bottom is probably from running too cold.
Reply:When striking the arc, strike it 3/4 to an inch in front of where you want to start, the bring it back to your intended start point with a short ark, any porosity/slag laid down in the strike up will be burned out when you weld over it.Using lincoln excaliburs, id run 115 amps doing stringer cap on a 6" sch 40 with 1/8, maybe 85-90 with 3/32, keep the ark tight and the rod pointing strait at the pipe. Sometimes i will do a slight drag from about 2oclock to 12, and i always use a very slight (maybe .030 side to side) side to side weave, as it will give you better edge whetting and a smoother toe, never, ever long ark, abd never strike the ark outside of the weld zone.Sent from my LG-P716 using Tapatalk