Random Erratic Possible Stalling Problem with router

[Neale]

I found a few of these drivers for sale but no technical details with a quick Google. Like Clive, I would suspect driver overheating, assuming that obvious things like physical jamming have been ruled out. I saw a very similar set of symptoms when I was setting up my 3D printer; the drivers would just shut down when they overheated and start up again once cooled. Given that your cutting loads are probably quite low, you could try winding the max motor current down a bit, and also check that the motor static current is set to half - if the drivers support these functions... At least, this should be easy to try.

I'm guessing that the machine stalls in different places each time, so physical jamming seems unlikely, but if you can disconnect the steppers easily it might be worth doing so and checking that the slides move smoothly.

After that - interference/noise, bad connection, etc - all much more difficult to track down