Momentary (Bump) Contactor for 330A/BP ?

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Does anyone here know where to get, or how to make, a momentary contactor switch for a Miller 330A/BP welder?Being that it has lots of amperage, as well as (I think) power factor correction, it seems like it would be a great power source for "bump welding" anodized aluminum, where you set the amperage at the panel, you don't use a pedal, and you "bump" through the anodized layer by hitting it with 100% of your panel-set amperage in short bursts. Basically, ON-OFF, ON-OFF, almost like you're tacking it over and over.Anybody here use their 330A/BP for this kind of welding?Edited to Add: I see in a 1975 manual for this machine that Miller used to make a momentary hand contactor for the 330A/BP. It was Model Number RHS-2G (Stock No. 041 157) but I guess it's no longer available...Last edited by Kelvin; 06-15-2013 at 11:55 PM.
Reply:I have not tried it but Zapster mentioned using the start current control, that would give u 100% of whatever the current is set for...  you could also turn the current to panel and the contactor to remote.   as soon as you step on the pedal you would be at whatever is on the panel setting...  that way though you would loose any current control with the foot pedal.  i tried it once but I discovered i needed to spend a lot more time practicing that specific technique...Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:Too bad you don't have the spot timer on your machine.  Sounds like what you are looking for.Otherwise, do what soutthpaw said, or add one of those torch switches that zip tie on your handle - plug that in for your contactor.Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:I just need to actually watch someone do this to see what its actually supposed to look like.    Also for say, 1/8 aluminum sheet,  what sort of amperage would u be using?  I am guessing well above what is used for same thickness that is not anodized.   Filler rod size suggestions too pls.   I am thinking it heat.  Super quick puddle, fill off repeat rapidly?Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:Sorry, Southpaw, I don't have any figures or sizes – just the general idea. I'll have to experiment.7A749, thank you very much for the offer ... please see your PMs.