walking the cup

[cami]

In my experience, suckback is a fact of life and adequate root reinforcement is the remedy. If your root goes in flush, then it'll be a mess after your next pass. If your root is good and heavy it should turn out fine. How much reinforcement are you allowed? 3/32" for the root and up to 1/8" for the cap has been acceptable for any test I've done, so stuff it in there!

[racer3j]

Haven't tigged since about 2001-but almost all of my Tig was on 4130 tubing, from ,065 to .083 and .095. From all of the years with OA and my most comfortable technique being the "keyhole," in a way I let the tig cup chase the rod. Yes, the rod feed dictated the torch movement. I did not walk the cup in literal contact with the weldment, but did introduce a very subtle "swing" and minute pull-back of the torch. So, as I chased the rod, the initial torch movement was a miniature "c" and a 1/16" pull back before touching the rod to the puddle. Except when constrained by a multi tube intersections, I also used a cup with 1/2" or the 9/16" mouth for broader gas shielding, just barely upping flow to get better shielding(Note-even on my mig I use a flowmeter-2 stage with floating ball and tube and analog round needle gauge)-- apparent average
bead width would be around 3/16" for the style of fabrication I describe.

My Dillon comes darn near tig control.They are not a gimmick. When I really need to limit heat area, I use the heat-stop "clays".mike