Fast Hole EDM from Hacked Parts

Yeah, 4K is a bit steep for us, but it is very cheap compared to alternatives in that category,
I keep planing to build an EDM power source, i did order a small spool of wire about 2 years ago through a friend in Finland, it never got delivered nor got his money back, so i have nothing to test with, i can probably build a usable mock up in about two days with stuff around the shops, so now you mentioned this, maybe i should also build a sinker and do the power supply so it works for both... thinking out loud.
So far wondering about ESP32, web server, LinuxCNC, is 12 bit ADC enough, what voltage/current MOSFET's i have, what voltage/current is required in a range of 1mm to 100mm cutting and 1mm to 30mm holes, etc, etc....
Sinker EDM does not require CNC, but it would be easier for positioning or doing multiple holes in one part, maybe?
Anyone interested to jump in?

IronManDylan wrote:

Can anyone speak to wether linuxcnc can be configured to run edm? Can it handle reverse feedrate? Are there any linuxcnc resources on running EDM? Thank you. 

There are several videos on youtube using it, BAXEDM uses it, he is a member here and lately very active, some other videos are probably 10 years or more old:
www.google.com/search?client=firefox-b-l...1142&bih=866&dpr=1.5

The words "holeflix and spotdrillfy" I made up refering to streaming platforms.

What I wanted to say is that it might be a good idea to pay someone to do the EDM part of the project. Provided it is only about getting the job done and not so much about toying around and experimenting.

To get good results with the technology requires experimenting and constant process control. (from what I could find watching youtube, and from  conversations) For a tap removal they charge me 6-9 USD, too less even to justify a cheap tap remover EDM. One time the neighbor set his oil on fire when he was trying to help me to remove a carbide end mill. We stopped the exercise at this point. 

To keep a nominal accurate diameter with acurate positioning is obviously not so easy. I saw a EDM tap. To get it to make accurate threads is not trivial. The secret seems to be the shape of the electrodes.

@Tommy: I would be tempted to jump in, in some way. I saw some comments somewhere that sinker EDM requires higher current outputs than wire edm.

The power requirements seem to be different (guessing from comments) between sinker EDM, wire EDM and hole drilling. 

I think a CNC sinker EDM can be very useful. Work with partial electrodes. e.g. using a small square electrode to clean up corners in blind holes, doing undercuts, threading etc.

Greetings Timo

 

i would seriously consider your options before you buy the rack thing, and also buy more than one if you really want it that bad.

how deep are you actually going?

since its for work, i would stray away from kickstarter tier stuff. not being able to actually adjust your settings is going to be a painful experience for you, depending on the spec of your hole.

if someone wanna chime in and correct me, but i dont think a short detect is really a control loop.

To get good results with the technology requires experimenting and constant process control. (from what I could find watching youtube, and from  conversations)

 

it does, and its called fast hole, not precise hole. depends on the spec, but overburn, combined with not being able to adjust the settings, runout from the setup, excessive electrode wear

Hi all, 


I apologize for the delay. I have been busy with this and another project. 

So the new rackrobo does have a way of modulating power output.  I was able to get my hands on a power supply at no cost to me. They are having some issues but it seems like the probability of an issue occurring is still pretty small.  If I do have issues I'll look at swapping the power supply. 

Yes I imagine sinker would draw a lot more power then wire and especially hole drilling. 


As far as linuxCNC control of EDM. Does anyone know if the ones like tommy was showing are using reverse feed rate and short detection?  It seems like it wouldn't be too difficult to pause the program when a short is detected, but does anyone know if it is possible to get reverse feed to pull out of the short and then reengage? I know this is how professional machines operate and I would think someone has figured out how to do this with LinuxCNC...  Any LinuxCNC wizards out there know how to do this?


Best,
-Dylan

Yes, reverse feed is possible and also used in EDM machines that use linuxcnc,