Hi guys,
I'm new here in the forum and new to the topic of CNC.
I've been cobbling together a very affordable 3-axis CNC milling machine for a few months now.
About the milling machine:
- Aluminum and steel profiles from the hardware store as guides, with 22mm ball bearings
- Working area approx. 80cm x 55cm x 2cm
- 4x NEMA 17 stepper motors
- M8 threaded rods as drive
- Proxxon FBS 12/EF
- actively cooled 2A stepper motor driver boards
- Arduino with GRBL
- universal G-Code transmitter
But now I have the problem that my milling machine doesn't do what it's supposed to. Most of the time everything starts well, and at some point the milling machine deviates from the intended path and mills something. Without warning and for no apparent reason. Since it is usually already quite deep in the wood at this point, everything bends and I have to switch the whole thing off immediately.
My theory now is that my Z axis stepper motors have a problem. Because when they slow down, at one point it looks as if they are getting stuck and then continue to turn again. The problem also occurs when the engines are removed. The driver boards aren't too hot, so that can't be the problem. I believe that there is a shift on the Z axis, but it is not noticeable because the cutter continues to move in the previously milled path (the cutter is not very stable). At some point the deviation becomes too large and the milling cutter then mills away from what was intended. Has anyone understood this theory and is it realistic?
I would be very grateful if someone could help me as I'm kind of running out of ideas.