need help tig welding pipe

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I have been tig welding pipe for a while but I just need help with my root. Most of the time I get good penetration but I still need help. I'm welding 6in schedule 40 pipe with a 1/8in gap I'm using 1/8 tungsten at about 95 amps filler is also 1/8. My main question is are yall running down or up hill and how are you feeding the filler metal. These are probably dumb questions but I just need some help. Thanks for the help in advance.Lincoln 225 RangerSa200            01 dodge  3500 welding rig
Reply:We do all uphill. I use what some call the "lay wire" technique for filler, unless the root starts to keyhole and I need to do a little dabbing.
Reply:I try to go up hill all the time. When you say lay the wire are you just keeping your filler in the root opening and working your torch from side to side? Thanks also for helping me out.Lincoln 225 RangerSa200            01 dodge  3500 welding rig
Reply:In all my years of doing tig roots i have never heard of a downhand tig root on pipe?  I weld various pressure piping/vessels at our coal fired power plant, (chromoly, stainless, inconel, mild) Alot of my joints are heavy wall due to the high pressure steam/water/acids. I use a 3/16" gap with just a very minimal land, im talking just a few pass's with a sharp file less than 1/16". I also use 3/32" rod for my roots, ( less heat input, less distortion, keeps you below that interpass temp if nessecary) also a 3/32" tungsten, and all our procedures require me to stay at 90amps which is pleanty. For my technique i freehand, i wash the puddle to both edges, once i reach the top edge i add my filler, not just a dab ill generally burn off 3/8" of the rod on each dip and then ill wash it down to the bottom edge and then quickly back up and repeat. I stay very tight to the gap, i dont wash up the bevel much at all, in doing this you can go quickly BUT you have to have alot of control and know how to use your heat because you can create a large keyhole quickly if you dont watch.
Reply:Thanks a lot guys this is very helpful. I always go uphill to I know a few people who prefer downhill that's why I was asking. I guess my biggest problem is I'm not burning enough filler because I generally do a dab or so that's probably where I get suck back. My root is the only problem I have. I  tig weld my hot pass pretty good and we use 3/32 7018 for a 3 stringer cap which I'm not to bad at either. Ill be practicing my root tonight and thanks again for the help guys keep the advice coming I can never learn to much.Lincoln 225 RangerSa200            01 dodge  3500 welding rig
Reply:Originally Posted by bgrovesI try to go up hill all the time. When you say lay the wire are you just keeping your filler in the root opening and working your torch from side to side? Thanks also for helping me out.
Reply:I run my pipe weld roots by letting it slightly keyhole then dip.. I try not to let it keyhole more than  1 size larger than my filler wire... meaning 3/32 filler,3/32 gap and maybe about an 1/8 keyhole... then dip about a 1/4'' of filler at each dip... this seems to work really well for me with a flush inside root and no suck back from my second pass...also all up hill welds...Lincoln pro mig 180Lincoln Square Wave Tig 300/wp 20/home built water cooler Victor, Purox, Harris, O/A welding/cutting setupsVintage Craftsman drill pressVintage Craftsman/Atlas 12"x 36'' lathe7''x 12'' w/c band saw Everlast 140 st
Reply:Thank you guys. I practiced not to long ago and I did the lay wire technique and it worked excellent for me. I used to dip after opening a key hole but for me it penetrates so much better doing this technique. I appreciate all yalls advice, and still am interested in more.Lincoln 225 RangerSa200            01 dodge  3500 welding rig
Reply:Our boiler inspector generally likes "more" than flush roots, generally 3/32 to 1/8" ive always been one of those welders that likes a decent build up inside my pipes i have seen time and time again guys have to cut roots out due to lack of fusion/suck back/wiskers(pieces of unmelted rod in root pass). Its just my opinion of course. Xray tech's like nice defined roots i find.
Reply:Yes sir I agree I to like a little buildup inside my pipe that was my only problem I had a hard time getting penetration around the six o' clock I more than likely wasn't dipping enough. I'm bend testing all mine and yesterday I had one spider crack on me on the root. I will bend one tomorrow and I'm pretty sure this is the best root I have done so far. Hopefully they will pass (fingers crossed).Lincoln 225 RangerSa200            01 dodge  3500 welding rig
Reply:I take that you are welding carbon pipe? I have always "fed" my wire. But it is from the inside. I dont have it on the outside of the bevel. Too much chance of leaving wall. I run a 5/32 gap and run 115 amps using 1/8 wire. 70s 6 is the best. Hope this may help you.My hood and I... Till death do us part
Reply:Thanks also for helping me out.