High electrode wear and instable burn with thin electrodes on my DIY EDM machine

Hi,

my newly selfbuild simple R/C EDM machine works well with 'normal' sized electrodes.

But with my needed slim sheets it only burns very instable and the wear is unacceptable (up to 300% vs Stainless steel (1.4571,V4A)) high.

The last thing I know to try is milling round E-Cu57 (sheet copper is a different grade?!) rods to sheets, finding the right graphite or try tungsten copper.

Has somebody any hints for me or is the only possibility for me to build a better pulse EDM ?

Does anybody know a good description for a pulse EDM matching my demands? (I have the pulse-EDM Book of Ben Fleming but its very complex without a microcontroller)

To make yourself a picture of my machine, my problems and my demands here is a YouTube Video: https://youtu.be/Gfj0BWwBAOA

Thanks for your interest and with best wishes

Ralf

I spent a few years as a toolmaker using standard manual and CNC EDM machines. There is a reason why fine detailed work needs more control than just your simple R/C setup. Fine work requires precise control of on and off times as well as current, voltage, frequency and polarity. If you simply want to burn out a tap then R/C will probably do. Fine high surface finish work is going to require some pain if you want to build a controller yourself. There is no way around it. It's a complex field with many variables. There are no shortcuts. Congratulations on what you have done so far. A great effort.

Maybe try using edm 244 oil instead of water? Just a suggestion. Also try and add more flushing. Discharge can build up causing erratic burning.