could use some advice/critique please-tig welds

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Back again. Running scratch start, 3/32nds gold band tungstens, #5 gas lens cup, 15 CFH of argon, mostly 120 amps. I am quenching in water every 2-3 beads or so. I feel a lot more comfortable welding beads on the thicker steel (1/4 and 3/8ths) and feel like I am getting more consistent, although I still can't determine how to get rid of the crater yet. but 1/8th plate is really driving me nuts, I can kind of get a not bad looking bead going if I back off to 90 amps, but at 120 amps, my beads are overheated and undercut. I have tried moving faster, using a larger filler rod (got some 3/32 to experiment with). I keep getting advice that I need to run 120+ amps on the 1/8th plate, but everything gets way too hot. The third bead on each of the 1/8th inch coupons is @90 amps. everything else is 120 amps. On the 1/8th inch coupons I quenched after every bead. The first pic is the 1/8th, the second is 3/8ths, and the last is 1/4What is the secret sauce that I am missing for the thin stuff (besides a foot pedal, which I know will be someone's first answer) and what is the secret to getting rid of the craters?Miller Multimatic 255
Reply:Seems like your craters are being caused by oxidation. When you snap out to break your arc get back in there as fast as you can to resume shielding gas on the bead. You may want to consider making a knife switch to break current. Jody did a video on welding tips n tricks about this check it out.Thermal arc 211iCk flex-loc 150 & 130Clamps, saws & grindersHarbor freight 80 amp inverter
Reply:Here's the link to that video hope it helps. http://welding-tv.com/2013/04/18/old...-with-a-twist/Thermal arc 211iCk flex-loc 150 & 130Clamps, saws & grindersHarbor freight 80 amp inverter
Reply:At the end of the bead you need to add a little extra filler, then move faster until you see the puddle "dry up". When the puddle has shrunk down you snap the torch away to break the arc then hold the cup over the end of the weld until it cools some to keep it from oxidizing too bad. Since you are welding to an edge, try changing travel direction at the end so you are pulling the puddle back until it "dries up".Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Its hard to tell but it looks like you need to reduce heat a little. Try moving a little faster and pushing a little extra filler into the puddle(either dip more often or add more per dip). Be sure to pay attention to arc length, hold as tight an arc as you can. If your not able to cool the weld a little using what I just said try turning the amperage down a little.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:louie; i was watching one of jody's tig videos and he was demonstrating scratch start tig using a miller t-bolt with a home made foot pedal utilizing an automotive knife switch. the pedal looked real easy to make and hook up plus the video was very informative.i.u.o.e. # 15queens, ny and sunny fla
Reply:Originally Posted by Louie1961I can kind of get a not bad looking bead going if I back off to 90 amps, but at 120 amps, my beads are overheated and undercut. I have tried moving faster, using a larger filler rod (got some 3/32 to experiment with). I keep getting advice that I need to run 120+ amps on the 1/8th plate, but everything gets way too hot.