Paul,
I can tell you the electrode is positive and the voltage differential is right @ 80vdc on high. The Rocklinizer power supply circuit is a little more complex as it can control the depositing of tungsten carbide to 10 thousandths of an inch. Since your burning away a broken tap or bolt that would be over kill. Total current draw is 8 amp @120vac 1 amp is for the cooling fan motor. Edm fluid has me doing research, the viscosity and flash point, it all seems flammable!

 

Thanks for the details. You guys are inspiring me to get back to this project soon.
Paul

 

Tap disintegrator's generally use anti-freeze fluid, and just to flush the electrode, not immersion.
In commercial EDM's the ARC is fed with DC with the work being Positive & electrode negative.
Max.

 

MaxHR,
This Rocklin set up seems to try to be both, Paul's is a little different than mine, I don't think he has a pump and uses hollow electrodes like my model 1000 is. Edm fluid is recommended by Rocklin.
Now your use of anti-freeze solution has crossed my mind as I seek a more coarse depositing of Tungsten carbide or ? for gripping surfaces on shrinking and stretching dies used in sheet metal work. Still need more info before playing with a welder in water! <grin>

 

I ran a sinker EDM for over 11 years at work. They first used a Texaco fluid, nasty nasty stuff, eats your skin up. Then when they bought some new Charmilles machines they switched to a new fluid called Ionoplus, great product, better burns, no skin problems. Never used it but the easiest to find, especially in small quantities is from Rustlik. MSC and Enco both carry it or did. But for home use kerosene can be used, but you need to keep the spark gap completely flooded to prevent a fire.

You don't want to use a fluid with the Rocklinizer when depositing metal though. Or it will not deposit but act more like an EDM.