nitris223 
Aluminum SCH 40 pipe.
Well I finally got my cart built and started using the Itig 200 DX. Played around with some 1/8" thick aluminum plate and was getting pretty good and running descent beads. After a couple of hours of that I moved onto steel. My steel beads suck big time. They look more like mig beads then stack of dimes. More practice I guess. Back to the aluminum I tried to tig some sch 40 3/4" pipe. It was horrible. I could not get a tack going for the life of me. It would puddle one side or the other. Add filler rod and it just turned gray. The more I tried the worse it got to the point it would melt a hole. I am using 2% lanthanated 3/32 tungsten and 3/32 4035 filler rod. I have just about used up the one lanthanated rod that came with the tig and I have to wait for more to be shipped to me. All I can get here is thoraited or maybe ceraited . Some times it would hold a nice small tip and the next time it would eat the electrode.
Still experimenting with the AC freq and Balance. I have to get this SCH 40 pipe figured out because I have a project that I need to do in about a months time. I have a tube notcher to make nice tight fit up. I wiped with acetone , scuffed with a wire stainless brush and then wiped again with acetone.
Also my welder came with a stubby kit and for the life of me I could not get it to work worth a dame. It would ball the electrode really quick. Do I need to run more gas with the stubby kit. I have it set so the top of the ball is floating just pass the 20 SCFH. No trouble with the standard size cups.
How do you determine which cup to use. For electrodes I only have 3/32 and 1/16. Cups go from 4 to 8.
I found that I only needed 85 to 90 amps to weld 1/8" and get nice beads. Maybe this is cold but if I go to 120 it seems to melt fast and I have to travel fast with a very flat weld bead after. It seems like I never put any filler rod in.
Another problem I seem to have is I can not weld a lap joint. I just melt away the edge of the top plate like crazy. Less amperage didn't\t help.
Well back to the shop to keep trying.
