I forget the details of the project now. Not to long after buying my Dynasty 300 I had to weld some 3/8-inch thick aluminum. I used some 1/8-inch Lanthanated, (blue) tungsten. Pushing 300-amps the Lanthanated tungsten didn't last very long before the tip started splintering. Kind of aggravating to have to keep sharpening the tungsten! Later I bought 5/32-inch tungsten, collect, and collet body, never used it. Then I read where people use Ceriated tungsten for aluminum welding too. 1/8-inch Ceriated tungsten can take 300-amps longer than the Lanthanated.
I like the results better if I keep the AC balance between 60 and 70, never go over 70! I play more with the frequency, for thin material the lower the frequency, the thicker material the higher the frequency.http://www.millerwelds.com/resources/articles/index.php?page=articles82.html
torch guy, one thing I find very helpful when high amp Tig welding aluminum, is a pair of those Ove-Gloves for cooking. :wink: