Pipe root w/ tig question

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Today I did my first root on a pipe in 5g.  Everything seemed to go well except for the 3-12 position.  This was the easiest quarter for me except that my gap was a little small compared to the rest of the pipe, so I decided to run 3/32 filler instead of 1/8 on this quarter of it.  IIRC the root was basically flush.  The issue that came up was there appears to be a crease down the middle of the weld.  Same idea as when a weld cracks only this was just a little crease.  1.  what causes this?2.  is this something that would cause you to bust a test on a root inspection?Filler was E80S-D2.
Reply:Ive never seen or heard of that before, so a picture would help.  It sounds like a section of incomplete fusion which would most definitely fail you on a test.  If not and its just a cosmetic issue then I would expect it to pass.Have we all gone mad?
Reply:If I remember I will take a pic of it tomorrow before I fill and cap it.
Reply:Probably a shrinkage line. Superficial and buff out easy. You may have hammered it with too much heat imo.Pluse was your back purgre good enough ??????
Reply:It was hard to get a close picture with detail but you can see it.  Root had just enough reinforcement that you could barely feel it with your hand.Not using a back purge.
Reply:Very common, it is totally superficial. I see it mainly in MIG. If anything, it shows how machine like your welding is, very steady.
Reply:We had a weldor on here by the name of engloid. He was very good, and I remember seeing that in some of his pictures. I dont think its badHTP Invertig 201Lincoln Idealarc SP250Miller 180 AC StickBy farmall:They should have held the seagull closer to the work, squeezing evenly for best deposition.
Reply:Your root looks VERY nice from the inside imo.No need for back shielding on carbon steel pipe.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:Originally Posted by fordmanWe had a weldor on here by the name of engloid. He was very good, and I remember seeing that in some of his pictures. I dont think its bad
Reply:The root looks good - nice and consistant. The only time the shrinkage line down the center becomes a problem is when you run hot without adding enough filler, then it can lead to a crack. Not a problem in your case though. Nice work.
Reply:That root looks amazing....Are you high? I wish I could put a root in that nice.
Reply:Well that is the outside face of the root pass, of course the inside doesn't look as nice.  I've had a little problem with root reinforcement so far, it has always been flush with no reinforcement.  Strangely enough on that pipe in the pic I had perfect reinforcement from 9-12.  The only difference was that it was done left handed.  I guess I was just going slower since it was my off hand.  Not as consistent on the outside but looked great on the inside.I just wish my fill and cap looked 1/10th as good as the root Another question- what orientation do you guys prefer when welding a pipe in 5g?  Do you stand and have the bottom head high, weld the bottom on your knees, etc?  We only have a little over a month of school left and I'd like to make every rod count and waste as little time as possible.  It takes so much time to bevel and fit a pipe that I don't get nearly as much rod time as I'd like to.
Reply:As far as positioning, in the shop I would have the pipe tit high so I can move around it. In the field we have very lille choice but I always make sure my scaffold is not to low or high. Your root pass looks very good! As long as your sides are broke down all around you should be fine. When welding the exotics alot of the time we have to dip our filler rod, this is running our tig rig to key hole and dip method. This will assure the walls are broke down and in some exotics  the filler metal melts before the base metal. I have run over the wire, fed the wire from the opposit side and dipped so all methods are good. You indicated your fill and caps are not as good, I was trained to take a ball glass jar and sit at home (while watching tv) and use just the tig rig head assembly with a large ceramic cup and practice walking the cup around the jar. After awhile you will get the feel and it will be much easier on your pipe, keep up the good work!
Reply:Thanks for the info trich.  I'm not as good with the dip method as lay wire but that is something I will practice on also.  I'll pass along the ball jar tip to my buddies, some of them said they have a hard time learning to walk the cup so maybe that will help them.   As far as the fill and cap, that is 3/32 7018 for us.  We only tig the root, some guys choose to also hot pass it with tig, but its stick from there on out. I wish we could get some exotics or even stainless to practice on but we don't even have enough time to do different methods on carbon steel.  Not to mention cost.  I looked up what 6" carbon steel sch. 40 costs because I wanted to buy some to practice on.  Just about dirtied my diaper when I saw the price on that stuff.