Buliding an EDM machine Arc generator

[ali_asadzadeh]

Hi
I have seen baxedm wire edm videos on youtube,The importatn thing there is the Arc generator,so I want to get Ideas,feedback and suggestions to build a new open source Arc generator, So any suggestion and feedback is welcome.

[moffy]

From what little I know about wire EDM, the voltage is pulsed through the wire at a variable rate, while the material being cut is immersed in a liquid, sometimes a mineral oil. The wire is continuously being fed through a spool and insulators, with a tensioner, and the cut rate is probably some feedback loop controlled by the arcing current. The electronics sounds fairly straight forward but the mechanics is where a very high proportion of the labour would be involved. You would also need specialised control software as well as the design software to feed into the controller. Quite a bit of work.

[Kleinstein]

In the simplest form the arc generator is just an RC combination: a capacitor to provide the power for short, high power arcs and than the resistor to recharge the capacitor. One can make a somewhat more efficient and make sure the arcs quench by using inductors and electronics.

The difficult part is really the mechanichs and also the system to move and clean the fluid. For the fluid the main candidates are deionized water and suitable oil. It also work with liquid nitrogen or similar.
Another point to whatch for the EMI - it usually needs some shielding to meet emission standards.

[ali_asadzadeh]

Thanks for the feedback, But lets 'not worry about the mechanical parts now, Since I have a friend that can do it for me, and it's super easy for him, since he has done more than 150 different Plastic mold design and manufacture them.

Here is the manual for the baxedm arc generator,
https://www.baxedm.com/wp-content/uploads/2021/02/BX17-Manual-Rev10.pdf

We should design a system that is capable of generating arcs with controllable on time and off time periods, along side controlling the arc current and voltage.

ISO-Frequency

ISO-Pulse

[moffy]

So you need an isolated variable power supply of 150V*30A*0.5 or 2250VA for 50% duty cycle (page 23). So you start with a variable voltage, variable current power supply then you can pulse that output from 40kHz to 200kHz at less than or equal to 50% duty cycle. The arc and motion control need to be integrated together in a control loop, and the pulses in ISO mode have a different characteristic. You are going to have to start with simple basics and then add features after you have the basics working. You are also going to need a machine to experiment upon, there is no magic wand, it will be a challenging mechanical design. First time doing something can have a steep learning curve and unexpected surprises. You need a motion controller board, which is also integrated with the arc generation. There is possibly a good portion of a man year or more in the design etc. Depends how experienced you are. It will also be quite expensive, prototyping has a way of adding up quickly.

[Mishko]

Hi, I'm Miso and I'm a total newby on this forum, but I was also searching for EDM generator and just stumbled upon the schematic for such a thing on the other website, so I thought you might want to check it, too. I just skimmed it so far, and I have no idea how good or bad it is, but you never know. Here's the link:
https://hackaday.io/project/181551-sinker-edm-machine/log/202201-arc-generator-circuit

Good luck!