help! having issues with tigging root in pipe.

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I'm tigging root in different sizes of pipe in 6G position. Every time I put the root in it stays flush, I'm unable to get it to crown. On 6" pipe 3/4" thick I have a 3/32 gap using 1/8 rod, size 8 cup on tig gun, 2% thoriated tungsten sharpened to a point, Lincoln invertec v-350-PRO scratch start. Temp started out at 118 but way to cold went to 135 it penetrates but stays flush. I have changed my temp thinking maybe I'm too slow causing heat to suck back I have changed me speed I move fast I move slow I have changed my cup to different size changed angle changed the regulator gauge on the argon every time I change size of cup and temp. I tried the dip and lay techniques. I have gone back and forth I have gone up and down, every technique I have read about. Nothing seems to work my root stays flush all the way around. Same with 12" 1/2" thick pipe and 12" 1" thick pipe. Any suggestions would be appreciated. My tig hot pass is perfect and my 7018 fill and cap is perfect. My root seems to be the only issue I'm having.
Reply:Push more wire into it.Two turn tables and a microphone.
Reply:Whats the issue with being flush?  I don't recall seeing anywhere that required minimum reinforcement on the inside.Have we all gone mad?
Reply:Try gapping it at 3/32, after you tack it it will shrink a little bit. Use 3/32 fill wire and make sure as you are welding that you have a key hole between the torch and your fill wire. Just enough that it still fills in behind you. You don't need to feed wire just lay it in the bevel in front of you. Another option is 3/32 gap and 1/16 fill wire and feed it into the very front edge of your puddle, you have to feed alot but it will push in. Next you can use a 3/32 gap and feed the wire into the back side of the puddle, your rod will be between the bevels, that is tricky but it works great. I use it alot when I have a bad fit and i am on the bottom since gravity isn't working with you. I do all three of these methods depending on the situation. Have passed x ray doing all of them. If you need any more advice pm me your phone number and i can talk you through it.
Reply:Originally Posted by sn0border88Whats the issue with being flush?  I don't recall seeing anywhere that required minimum reinforcement on the inside.
Reply:@ snoboarder on pipe your allowed flush to 1/16" reinforcement on root and that is going by AWS regulations. Its a must on certification tests. They are strict and measure everything. So if I start out with it being flush then run my hot pass the heat causes it to suck back in some areas where gravity is against me. Causing me to have insufficient reinforcement. Plus I'm still in school my third semester of college flush isn't good enough they want it crowned. @ Chad thank you so much I have been stuck on this for a month all the other pipe positions I flew through no problem 6G is the only issue. I will give all your suggestions a try Monday when I return back to school and let you know how it worked out. If I still can't get it I would appreciate it if you would walk me through it.
Reply:No problem, talking is a lot easier than typing especially when i am typing on my phone
Reply:My instructor who also works for a  local boiler company, told me to fill more on your second pass and to use about the same amps as I used on the root pass..  My roots are  also flush or maybe 1/16 or less on the inside...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:I'm aware of what the code requires and allows, I took my D1.1 with TIG root/7018 Fill a few years back.  If your hot pass is as good as you say it is then flush is just fine, its really hard to get more than 1/16" of suckup from a bad hot pass.Have we all gone mad?
Reply:Originally Posted by sn0border88I'm aware of what the code requires and allows, I took my D1.1 with TIG root/7018 Fill a few years back.  If your hot pass is as good as you say it is then flush is just fine, its really hard to get more than 1/16" of suckup from a bad hot pass.
Reply:Just wanted to let everyone know I bend tested today, I passed, it was perfect....thanks everyone for all y'alls help!!
Reply:Thanks. Always nice to hear when people can make use of what information is available here and how a situation turns out. Good luck..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan