greets all, i want to thank everyone for all of the great info in this NG.. i've been reading the archives for days and my brain is swollen.
last week my Cemont TIG (160 AC/DC HF) showed up and i've been having a blast -- i went right for the aluminum! i must have cut and cleaned an entire 4'x8' aluminum diamond plate into 1"x4" coupons. (ps.. anyone know what alloy AL diamond plate is usually made of? the stuff they use in truck bodies, etc)
the Cemont is a small inverter with decent control (though not full).. i can control the AC balance from -20 to +20. after some trial and error on this aluminum plate i find that maxing it out at +20 seems to do the best job. nice clean shiney beads. the button is kind of small, and i couldn't distinguish between, say, +14 and +16... how sensitive is AC balance? and why wouldn't i always use the highest setting? (considering, +20 is my highest setting) ... i realize this gets me more 'cleaning' and less 'penetration'.. but couldn't i just up the frequency, or the amperage, and make up for the loss in penetration, while keeping the increased cleaning action?
around 60-80Hz AC seemed to work well.. however, i was getting drastically different sized heataffected zones / deoxidized zones around my weld beads for what seemed a small range in freq (60-80hz) ... is the goal to keep the heataffected zone as small (or tight) as possible around the weldbead? some of the beads had 'halos' around them as wide as the bead itself, on both sides.
last question.. not a biggy and i may outgrow this: my torch is terrible! i have a different DC only tig with a flex head torch that i can bend 'round however the job requires. this torch is fixed and its HEAVY... most of the time i'm fighting the twist in the cables. Cemont does not offer different torch styles (just sizes)... are these things more or less interchangeable? can i get a different torch, throw in some fittings and use it on another machine? again, this may not be a big deal -- i might just have to get used to this new torch.. but it doesnt seem likely.
thanks again for all the great info i'm sure i'll be posting more on this as my experience (and confusion!) grows