When I'm installing the J6 limit switch for the MK3 I've noticed a few issues. Not sure if these are user error or if these are known issues that have a fix.
The 2.5x8 pan head screws do not want to thread into the 3d printed J6 limit switch mount. The instructions also call for 2.5x6 but the BOM lists only 2 of these screws. The 6mm screws are also not long enough to thread into the mount.
When mounting the limit switch with the switch closer to the side of the J6 bearing cap, the limit switch does not compress when the limit contact contacts the red portion. Instead, it just presses on it perpendicularly and does not activate the limit switch. (Granted this is with me moving it manually). If I mount the limit switch in the opposite orientation, the switch actuates well but this seems to incorrectly calibrate the J6 joint.
Please let me know if there are any fixes for the above issues or there are any steps I may have done incorrectly, I'm almost done with the assembly and am very excited to get the arm moving!
the 3D printed mount should attach to the aluminum housing using 2.5x6 screws and then the switch itself fastens to the the mount using 2.5x8 screws. I think I have a typo in the manual that I will fix - sorry about that. The holes in the mount do need to be tapped with a 2.5mm tap. If you can send pictures showing the issue you are having that may help. Please let me know what other questions you have.