Hole Popping with Copper Tubes

Hey all,

I have a steel block that I need to do some hole popping and then wiring on. There are four ejector blades on this block with a width of .062 thou and run 1.5 in. deep, ideally I'd run a .040 thou(1mm) brass electrode for hole popping but that'd only leave me with a .011 thou a side and I'm not all to familiar with our hole popper and I am worried that it may over-burn/and or leave some sort of marking or be out of place from that .062 thou hole. So I was going to run some .020 thou copper electrodes instead to give myself a little extra wiggle room for error. But upon looking for values to set my hole popper to i.e: T on, T off, IP, and servo voltage, there isn't anything in my book to help set these values. Anyone have any data on copper tubes of this size that could help me out to pop these holes?

Thanks,
-AGMantz

3rd set of numbers (.5mm with water) first row of settings is what we use.