Hi con_fuse9,

The 'bike I'm working on - a Harris F1 - was hand-built in very limited numbers (about 6 of them, around 1987-89), fabricated from individual pieces of box-section alloy TIG welded together. The seat sub-frame that I want to build is a seperate item, bolted to the main chassis - so I've no concerns over messing up the original 'bike itself whilst I learn to weld.

The material I'm using is 1/2 inch box-section alloy, either 6082, or 6063 - 3/32" wall thickness. Tungsten is 3/32" 0.8% Zirconium, cup-size is 7/16", filler-rod is 3/32" aluminum with 5% silicone - shield gas is Argon.

I find that with a foot-pedal 80 Amps is fine, I'm only using all the Amps on start-up to get the puddle formed, then backing-off as I run the weld. 75% balance seems ok, I've tried playing around with this but it doesn't seem to make allot of difference - maybe I'm missing something(?).

With the frequency I'm finding 120Hz gives a more focussed arc, a more controlled weld puddle, and I can control penetration better with my travel speed. Early days yet, so maybe as my technique improves I'll come down on the Hz a little, but as you say - personal preferance maybe.

Thanks for the advice, it's still early days - reckon I'm going to need a fair bit more practice before I get to the skill-level that I'm looking for