(R1 Beta) Z A & B Drives 20mm corner screws struggle to engage with brass inserts

[Foofinator94]

The 2 off M3 x 20mm screws on the corners of the Z drives have poor engagement with the brass inserts.

A combination of screw thread tolerance, printing tolerance of the clamped part height and counterbore overhangs, and brass insert geometry hamper engagement of the threads.

Suggest to either:

• Increase the counterbore depth to expose more threads to engage in the brass insert (~ 0.5-1mm suffice).
• Increase the bore depth of the brass insert hole to allow M3 x 25mm screws to be used instead of M3 x 20.

[warasilapm]

+1 I also experienced this during my build this past weekend.