for beading I like to use a fair amount of positive force w/ mine - nearly maxed out - gives you plenty of "power" and space it a bit tight - all depends on your spacer (and if he fits it consistently) and or how you fit the joint
Thanks for the suggestions. Ive been runnin it at about -2 from bead to cap and it welds good. Ill play with it and run up in the mid to high positive on the bead and see how it does.