Attempting tig welding pipe (AGAIN)

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Didn't want to drag out a big project because of the weather today so figured I'd try tigging pipe again. After watching some more videos, think I have a wee bit better understanding of what to do. I'll figure this out eventually just don't have enough time to practice4" sch4037 deg bevel machined on the latheKnife edge1/16" gapCleaned inside & out120a3/32" tungstenTacks made with 3/32" filler#7 gas lens9:00 tack outside9:00 tack inside3:00 tack outside3:00 tack insideSent from my SPH-L710 using TapatalkTOO MANY TOOLS & NO MORE SPACE
Reply:needs more gapthat's a pretty gnarly looking tack, sure you got the right wire?
Reply:You are moving too slow. Timmy is right, go with a 1/8 gap.
Reply:Timmytig,Think it should be 3/32" or 1/8"? This is my second real attempt at this and the first try was 1/8" gap 1/16" land which did not work well.What are yor asking about on the wire? I'm using er-70 filler, think it's s-6 if I remember right. Did not brush them off or feather the ends yet.Sent from my SPH-L710 using TapatalkTOO MANY TOOLS & NO MORE SPACE
Reply:1/8th gap should work out. That 3:00 tack has some kind of weird crust on it.
Reply:You should be able to feed the wire from the inside of the pipe.  Thus 3-4mm gap.
Reply:It's been raining here since lunch time. Guess this will not be finished today.Sent from my SPH-L710 using TapatalkTOO MANY TOOLS & NO MORE SPACE
Reply:Are you walking the cup, or free handing?Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:That was a VERY poor attempt at cup walking, couldn't seem to get myself positioned right. Had the handle of the torch parallel to the gap and it just did not feel right. I seem to do better free handing most stuff except for fillet welds.I seem to get too tense when welding pipe and always end up in a bind going from 1/4 to 1/4.Sent from my SPH-L710 using TapatalkTOO MANY TOOLS & NO MORE SPACE
Reply:One thing that might help you is to clean the inside of the pipe, at least 1/2-inch back from the edge. First off the disclaimer: I'm no pipe welder, or Tig welder. But what works for me, 37 1/2-degree bevel, 3/32-inch gap, 1/8-inch filler. Take a 40-grit sanding pad to the bevels. Take a mil file to the out side edge. Grind a slight bevel on the cup. Extend the tungsten out where it is really close to the filler rod. Push real hard on the filler. When walking the cup it's all about the angle of the tungsten. Run between 90 and 95-amps for the root pass. Always weld the tightest gaps first! For the hot pass, switch to 3/32-inch filler, and don't go up more than 10-amps to prevent suck back.I forgot to add, try to keep the root pass the same size as the 1/8-inch filler rod. Maybe just a hair bigger is all! Attached ImagesLast edited by CEP; 07-06-2014 at 06:19 PM.Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Not exactly the easiest pipe joint to start learning on. They have the day students start out learning on 1G since it's the easiest and all they have to do is weld flat while maintaining a consistent angle and roll the pipe as needed.  2G would be next since you aren't changing the weld position as everything is horizontal, even if the pipe is fixed. 5G like that, you are going to have to transition thru overhead, vertical and flat while doing the weld. that's tough  to do on it's own. If you are learning to maintain a consistent angle of the torch in relation to the pipe center as you go around, it becomes even harder..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
Reply:There are basically 2 methods to weld the root pass.Method 1 consists of a gap smaller than or equal to the filler rod used. It is faster but if you are not careful you can get lack of fusion and/or penetration. Also you have to be careful not to get any suck back especially on the bottom of the pipe.Method 2 uses a larger gap than the filler rod, usually large enough to account for shrinkage during welding. The rod is fed from the inside of the pipe. It is a little slower but it is almost impossible to get lack of fusion and/or penetration. Also if you learn to look through the bevel it is a lot more comfortable since you don't have top bend a lot when welding the bottom of the pipe.Most pipe welders I see use method 2.As I wrote earlier you are moving too slow. This is evident from a number of things such as:- Large haz on such a small weld area in this thickness- Large keyhole on the end of the tack- Too thick and too wide root passI would forget the cup walking for the time being and focus on free hand. Practice cup walking on the second pass as it is easier.
Reply:Agree with DSW.  You can try a 5g but so much is happening that you really don't have a chance to learn anything.   Pick a position to practice and the answers can be better directed.
Reply:Like others start with a 2g position its good practice, 5g personally is the hardest position to master. 3/32"-1/8" gap, 37.5 degree bevel, 3/32" tung,  smaller tacks with less amperage I use 90 personally, feather if you feel the need, clean really good between passes with a wire brush and let it cool a little between passes. I go up 10 amps per pass.... To practice cup walking try just laying beads around the pipe (not on a open joint), practice with both hands  When I walk the cup I tend to hold the torch upside down with the base of my hand towards the nozzle.It looks like your outside, that can be tough if your shielding gas is disappearing in the windAWS 17.1, D1.1 and ASME IX (GTAW)Miller Syncrowave 350LX, Maxstar 150sth, Maxstar 200DX and  Millermatic 252 w/ Spoolmatic 30aMiller buzz box with Lincolin TombstoneThermal Dynamics Cutmaster 38
Reply:I apologize for the late response as I've been very busy between work and laying out the new shop.Thanks for the suggestions, I'll give them a try and see how it works. Definitely going to switch to the 1G position to make things a little easier. I might set the current coupon up in 1G just to do a dry run WTC and make a new coupon to do some actual welding on with a larger root and lower amps. I was using a large gas lens and the wind was fairly calm and not disturbing the gas so much but I have some shields if needed. I was close to the garage door too which helped block the wind, rolled my stand under the patio because it was lunch time and it started raining  The inside of the pipe was cleaned with a 60 grit 2" flap wheel on a die grinder and it worked fairly well but the pipe was free (very rusted) so a burr might be better for cleaning that out.TOO MANY TOOLS & NO MORE SPACE