Tig overhead questions

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Ok I'm working on tig overhead, tried doing a butt joint on 16g but I couldn't keep it from blowing holes at 55 amps with a 1/32 gap using 3/32 filler.  Since we dont have any 11g I had to use 3/16 but no idea as to the gap so I made it a loose 3/32 using 3/32 filler and the amps set to 105.  The face of the weld looks spot on but the root does not go all the way through to the back of the plates and I'm at a loss as to whether I should increase the amps or widen the gap to what ever comes after 3/32 ( sorry but measurements is something I've never learned ) or do both.  I had to stop working on this and went to stainless 16g doing butt joints 1/32 with and without filler, with was a breeze but without I had to do as flat joint with no gap because the edge would recede into the plate body.
Reply:I'll try to re-create your 16g problem tomorrow. For the 3/16 plate, I would suggest either turing the amps up, or more likely slowing your travel speed down. Doing over head work can be uncomfortable which may make you move faster than you should just because you want to be done. And worrying about your puddle dropping out down onto you can make you pick up the pace. So I would check you travel speed first, if thats not it, turn up your amps, if that doesn't work I'd widen the gap to 1/8. But thats just my  opinion. Doesn't your teacher give you specs for what you're working on?For the stainless without filler, give it just a tiny bit of juice to melt the surface, but not clean through the plate. And don't start at the edge of the plate. Sart in maybe 1/2" from the edge. Just work the arc back and forth between the two plates slightly, with just enough power to melt the surface. Once you get the molten metal to cross the gap you can give it more power. Back up to the start of the plate, then run it normal. Once again, that's just how I'd do it.
Reply:A bit of bevel in the gap will do you better, and then try keeping the pieces closer together. A 3/32 root opening is ok for 3/16 and overhead tig. And I'd keep my foot out of the pedal a bit to keep from blowing through the keyhole. I also like what Grimm said.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:Excellent advice from both of you gentlemen!  I now know that another part of the issue is that the stainless is warped creating air pockets between the plates with my lap joints that I worked on yesterday and will revisit today with a proper clamp to correct the issue.At the moment no the teacher isn't giving any guidelines and I have to refer to the hobart book for information.
Reply:I would bevel the 3/16 and on the sheetmetal, tack it every few inches or clamp a thick piece of metal near the joint along it's length to help keep it from warping up.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Originally Posted by DesertRider33I would bevel the 3/16 and on the sheetmetal, tack it every few inches or clamp a thick piece of metal near the joint along it's length to help keep it from warping up.
Reply:Upped the amps 5, 10, and 15 and still had the same problem so I will be putting a bevel on the plate tomorrow when I go in.  I wasn't able to do anything with the stainless thanks to a pounding headache and a crappy attitude that I let the instructor have a small bit of when I told him I was headed to the library to work out my problem since I wasn't getting it done in there, he said I should have come and got him which I did the other day and he told me to just flip the plate and run another pass to fill the open root, I'm there to learn how to weld right not weld like a Chinese welder.(Nothing against Chinese as a people I just don't like their lack of production quality and pride in workmanship )
Reply:You will get it; it's nothing more than the 3 basic things; practice, practice, and....practice. I only met one person who got tig right the first time SHE did it. And for the record, she had never welded at all before. When she tried mig??? It sucked. Looked terrible. But she had a feel for the magic wand and filler. Go figure.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:The bevel is a good idea. Would have recomended it but I thought you were intentionally working on a square groove joint. Also might try sharpening your tungsten to a blunter angle, or putting a larger flat on the end to help increase penetration.
Reply:Just supposed to be a butt joint but it doesnt call for a bevel though that was on 11guage plate.  The metal suppliers in the area are slow to get material out so I'm having to make due with 3/16 plate.  Sharpening tungsten right now is kind of like trying to floss a lions teeth.  The bench grinder that isnt on a bench but a cobbled together car rim+pole+plate shakes all over the place because the stones are sitting on the shafts properly so I'm having to use my bosch grinder to sharpen tungsten till the new sander gets here and that depends on how quickly the distributor can get his 400lb butt out of his chair and how quickly the schools accountant can get a PO out to the distributor.  I've got this plus two more stainless to do then I'm on aluminum which I need to have finished by next Wednesday.
Reply:3/16" overhead, I'd only be around 80 amps....3/32" gap, 3/32" filler, bevelled edges.  I think everyone should learn (or at least try) tigging without an amptrol.  It just adds extra variables.  After you bridge your gap,  continue feeding wire to bevel points while moving torch only the width of gap, holding just long enough to fuse bead.  Expect a convex bead appearence on bottom.  Enough practice and the bottom will flatten out but will probably still have 'wagon tracks'.  I always touch these with pencil grinder before hot pass just to be safe. Attached Images
Reply:Originally Posted by Big65moparJust supposed to be a butt joint but it doesnt call for a bevel though that was on 11guage plate.  The metal suppliers in the area are slow to get material out so I'm having to make due with 3/16 plate.  Sharpening tungsten right now is kind of like trying to floss a lions teeth.  The bench grinder that isnt on a bench but a cobbled together car rim+pole+plate shakes all over the place because the stones are sitting on the shafts properly so I'm having to use my bosch grinder to sharpen tungsten till the new sander gets here and that depends on how quickly the distributor can get his 400lb butt out of his chair and how quickly the schools accountant can get a PO out to the distributor.  I've got this plus two more stainless to do then I'm on aluminum which I need to have finished by next Wednesday.
Reply:Ok I finally got the root on 11g plate ( got it in late yesterday ) at 100 amps down from 105 amps.  I had a little bit of suck back but the root went all the way to the top edge of the plates so I'll need to cut the amps back a tad more to say 95 amps and retry on Monday.  I used a lay wire fill method only pushing it in a bit extra if needed which only happened once, I also slowed my travel speed down sweating away the worry of a falling glob.On the 3/16 plate I can't see doing it at 80 amps at least with my miller 350 cc/cv but it might be doable with a real slow travel speed over what I had.  Doing the overhead tig I'm still not sure where I should be positioned to best view the arc as well as the gap so that may be playing into my issues but at this point I have it nearly down now thanks to the advice of everyone in this thread.
Reply:The only possitions I've found comfortable for over head is either laying on my back or hanging upside down. Anything else just gives me a crick in my neck. But thats just me.