Sinker EDM machine based on diy pulse generator

Hello,

there are already some threads about this, but most of them never continued the topic or vanished. So I wanted to start another (that hopefully not has the same fate). The topic would be homemade sinker edm machine with a pulse generator. Is it possible? I just had some thoughts:

- Using the pulse generator based on Ben Flemings book (Build a pulse edm machine), but replace all the knobs and pots (if possible have not checked yet) with software and/or relais and control them via a gui.

- For simple jobs use a G1 Z-??? F??? and then somehow measure the spark gap and use motion.adaptive-feed to adjust it. The feedrate could be trial & error. Add a timer that every x seconds sets motion.adaptive-feed to -1 (or more than 1, have not tested that function yet) to lift the ram up and flush. Then use the spark gap value again to move down.

- With a XYZ(C) machine maybe even orbiting the electrode?

- Has anyone here build the Ben Fleming pulse generator?

Just trying to gather information before jumping deeper into this topic.

Thank you.

I just worked through the Ben Fleming circuit (not 100 % yet). It seems that the voltage is ~ 100 V DC and the current can be limited by power resistors. A couple of mosfets get pulsed by a 555 timer, the pulse duration is set via pots. I replicated part of the circuit in LTSpice an ran a couple of different pot settings to get an idea of the pulse on and off duration. Also compared these values to commercial machines. The calculated frequency is ranging from 0,5 kHz to 60 kHz. Do I even need the 555 timer and the two pots or could I use PWM signal from linux to do that? A mesa card can go up to 386 kHz so should be plenty of room for that.

tommylight wrote:

All those can be easily done with any microcontroller, but might need better ADC converters.

That would be important for the voltage gap feedback. Would an off the shelf voltage to frequency converter work for that?