Sunday, March 22, 2026
Tweak to the Flexure Coupling
After seeing Jon struggle to fit the Flexure Coupling to his RepRapMicron stepper motor, I've reached the conclusion that relying on precise printer dimensions for shaft fit is foolish. Coincidentally, I appear to have stressed my X Axis Flexure Coupling to the point where it cracked (see black mark):
This was caused by me tightening the Drive Screw down too much, but spurred me to modify the Flexure Coupling to have a conical hole in it (on github and Printables). The gentle taper makes it easier to start pushing the motor shaft in. The downside is that different printers and shafts will bottom out at different points. Still, there's a few mm adjustment in the design, and spacers in the print file for adjusting for gros shaft length.
The cracked flexure also explains why my X backlash increased after I fiddled with the Axis Driver. I'll fit the new one and see if that fixes it.
