Practice your ARSE off, especially the root. Like Kix said, try to find out about exactly what the procedure, specifics & setup is, etc. Then, get practicing on it. All the books in the world won't touch time behind the hood, especially being it's a GTAW root. Practice, practice, practice!!!! Hopefully, you have the circumstances to do so. If you're not accustomed to doing this kind of welding, I wouldn't suggest trying it cold. Even the best weldors blow tests sometimes. I don't care how good they are, or often they're doing it. If they haven't, (or say they haven't) they have just been lucky so far. Set your mind to it & you will do it, no problem. Good luck! :-) S.W.