I got the PowerPro about a month ago. It welds steel beautifully. However, when I tried to do aluminum, I encountered tons of problems. At first the arc was jumping everywhere. Then I accidentally turned pulse on (low, 125 freq, ~50% bal, ~50% time on) and I was able to run a few good, clean beads on some 1/8 U-stock stuff. I tried butt welding that piece and some 3/4 square stock (~1/8 inch walls) and I had trouble, but I think that this is mostly my technique. I have some 1/4 inch bar-stock stuff that is (or at least appears to be) nice and clean, however when I weld it (this is from memory, but my settings were: Pulse: Off, Foot Pedal, Amps-150, AC Frequency: 100Hz, AC Balance: I tried 10%,20,30,40,50,60,70,and 90 and they had the dirtiness problem (I'll describe this more later) or it ruined my electrode, Start Amps:0?, End Amps:0, Pre-Flow:1 sec, Post-Flow: 3 sec, Up-Slope: 0, Down Slope: 0, Gas: 100% argon @ ~20cfm, tungsten: tried both pure, lanthanated, and rare-earth (green, blue, purple)) I end up with either this gross, sooty, massive ugly trail of ruined base metal or my tungsten gets destroyed, depending on my AC Balance setting. I am always running AC on 2T mode (not sure what the difference is between 2t and 4t, haven't bothered to look it up). I also try to add filler into whatever puddle i get but usually I somehow either touch the tungsten to the base metal, ruining it, touch it with the filler, ruining it, or touching the filler to the very vague excuse for a puddle and it melts into this big glob on the end of the filler rod which I then usually just flip around, do the same thing to the other end, stop my arc, and cut both ends. Any help on any of these things is appreciated. I have never TIGed before and I am told I should start with steel which I did. I'm sorry that you had to read all of this.