TIG parameter advice

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I did a run in new to me position last night.Dynasty 200 DX3/32" 2% lanthanated electrode sharpened to some inaccurate but sharp angle110A, feathering the pedal but mostly flooring it200PPS/60% high/40% backgroundvery small arc length compared to flat positions I'm used to14 gauge/0.078"/2.0mm checker plate mild steel0.060"/1.6mm ER70S-6 fillerI don't remember, maybe 6 or 7 Lpm (12.5-15cfh) argon4F position with continuous plate on top, vertical plate butting to itSanded clean with flap discsBackyard hobby welder, newish to tigI set myself up for a fail because it was dark and at the end of a long day. I could have (probably should have) tipped the job over and did it in 2F. The corresponding 2F at the bottom of the sheet was fine and went as expected. The 4F part by comparison made a very small puddle. I dipped much less (because the puddle was smaller). The face length was about 2.0mm. When I got quite a way through I happened to look at the top and I got what I guess would be called significant suck back off the top of the plate. No holes, but it must have been close at times. After that I tried to dip a lot more with more success but some suck back still.So it ended up being a 75% autogenous weld I guess, compared to how much filler I'd normally put in. It certainly looks on the top like I'd run an autogenous weld straight along the top, with undercutting and a "canyon".In this situation (4F or 3F), should I bump up the amps and move quicker (with more dipping)? Is that the normal practice? If I was stick welding that's what I'd probably have done. I was surprised at the big difference between 2F and 4F and the results I got. In 2F I get penetration (visible on the back side with noticeable HAZ and some cracking of the millscale so my parameters are good enough for me there. I just don't want to over penetrate in 4F.
Reply:Not enough amps as you have pulse engaged. You were probably getting suckback above the root because pulse tends to flare the arc, especially above 140pps. I would turn off pulse and get a more direct arc in the root and chill the puddle with filler.  You listed gas flow but you did not list cup size. I would suggest a #6 and 15cfh, but that is me. Take this for ponder as it is just my initial impression. Different strokes for different folks.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Oh, cup size was #5 I think? Maybe #6, I'd have to check.I thought pulse because I like it for directing the arc especially into fillets. I thought it did the opposite to flaring, I thought it concentrated? That's the feeling I get, but as I say I'm a relative beginner.
Reply:Originally Posted by metaljongOh, cup size was #5 I think? Maybe #6, I'd have to check.I thought pulse because I like it for directing the arc especially into fillets. I thought it did the opposite to flaring, I thought it concentrated? That's the feeling I get, but as I say I'm a relative beginner.
Reply:I wasn't thinking of AC, but I've just about exclusively pulsed with my machine so I don't have as good a basis of comparison as with no pulse. About the only time I go with no pulse is when tacking. Maybe I just misunderstood and conflated "wander" with "focus". I'll try welding without for a while. My ears are thanking me already.