Get your hands on the Miller "Gas Tungsten Arc Welding" book. One of Miller's engineers (Mike Brace) is "in the house" from time to time, maybe He'll see this post and help you. It's a very good publication on the process. Miller also has some neat little tests that come with some of their publications. These books are also priced for the student. A very good deal for the $$.
(800) 4-A-MILLER