After many delays and set backs I’ve finally gotten a working, reliable PCB mill. In the first post I did of this, I used V bit’s to get better resolution of the tracks. The height issues remained and I was unable to get the auto bed leveling working on the Marlin firmware.
What I did to fix the multiple issues:
- I found the X and Y couplers were a poor choice, as they were acting like large springs. I added lock nuts to the far ends of the X and Y axis, on the outer edges to pull the couplers tight and prevent X and Y axis from springing back when they moved.
- I removed some PLA from the Z stepper mount to make way for the extra spindle length. That was not enough so the spindle mount base was reprinted with an additional 5 mm clearance from the stepper motor mount. Now the spindle doesn’t rub against the Z stepper mount when raising and lowering.
- Changed the V bit to an end mill, now the diameter of the tracks are consistent.
- The auto leveling requires the G-Code “M420 S1” to use the values, and the bed cant be too warped, for it to work correctly.
The modifications above have allowed for consistent cuts with a 1 mm end mill. I have ordered smaller bits to improve the accuracy and I’m still troubleshooting a random issue changing the start height from 0.1 mm to 0.2 mm difference.