Miroslav, thank you for showing your project.  I have a question about the OS for the Raspberry PI.  Are you using Raspbian OS?  If you are is that OS better suited for your project than the Windows 10 IOT.

I am looking to start a project like this for my milling machine.  Thanks for your help.

Hey Miroslav

I've built a laser cutter based on your board. The only one missing piece for me is how to control the laser (turn on / off). As your board is based on the Protoneer it should have a pin to control the spindel. So far I was not able to identify the pin. Can you help?

Thanks!

Hi,

zdravim hackerspace Pardubice, tusim ze tam nekde bude i Kuba vodrha, na chalupe se mi hromadi material na cnc router, coz bude chtit silnejsi H bridge, cekam na nejaky ukoly s kterejma bych vam pomohl, jinak jsem z podebrad

Zdravím, 

bohužel jmenovaného Kubu neznáme. Co myslíte tím silnější H bridge? Jako výkonější krokové drivery?

I'm very interested in this!! Is there a better place to look for information? The wiki site http://wiki.rpicnc.org/ seems to be done.

Also, what would it take to test your circuit? Just the board and the components assembling it? Any additional PCBs?

Hi James, 

I´m sorry but i did not complete my wiki page and I was also to eager put my project here, so I completely forget that change that link. I will fix that link and execute my wiki asap. What information you are seeking? 

To test my circuit you just need my board and components which are listed in component section. No additional PCBs are needed, except RPi of course (or not, it depends how you want to control it).

Is there any way you can send your board design? 

Talking with a few coworkers to see if I can allocate some funds to fabricate and assemble the board and repurpose a spare CNC machine we have lying around somewhere. 

Drop me your address to PM and I will ship you one board if you want (with or without components) ;-). I don´t want release files yet, sorry. 

What sort of max stepping rate can you get on a diagonal (ie 2 axis moving in sync) ? There is the PICnc project over on the raspberry PI site that does something similar. Downside to that one for me was the max stepping rate was limited. I am looking for a controller that can drive laser rastering and the PICnc project was just too slow. Also what NC software/packages are you using to drive the setup?

Never mind just found the link to your other page. Makes more sense now as your not using the PI as the step gen and its more of a standalone controller that happens to sit on top of a Pi. 

Nice Idea... my main concerns: The small trace from the power-in-screw connector looks much to weak for me to handle the max. current of 4x2x2A = 16A looking at worst case with all coils taking 2A...

This trace will heat up a lot.. i guess it's 2mm/35um Copper so an with only 8,5A it will heat up by 60°C over ambient.... you have to make it much bigger.

Also the screw connectors are imho not suitable for higher currents then 2-4A.

Hi Thomas, 

thanks for your thoughts, I really appreciate your opinion.

I don´t think that there will be so much current at one time, but I will make traces as big as possible in next revision. I have to look for specs on that screw terminal, but I will probably swap it for bigger one as well.

Hey Miroslav, cool!
I'm currently building a CNC-Machine out of a Ikea Table. With 4 A4988 stepper drivers. If will do a measurement tomorrow and give you a feedback on the current that i have.

https://hackaday.io/project/12712-ia-cnc-machine

Thomas

Something like this has been needed for a long time!