What is this - broken Z Coupler?


:( :( :(

Z motor untighten ?

as told in at other place, most likely a loose Z-Couple. Just try to fix the set screws.


Looks like it has been broken for some time with the 2 wear spots. And your prints been coming out ok?

I noticed it sounding odd during the last print, which ran all night, but it finished and came out OK. When I went to run the printer the next morning the coupler was broken and the Z axis didn't work. Anyway, it's back in action now :)

Mechanically speaking, that is a common problem when the motor and shaft do not have a close alignment and they use a weak metal flexible coupling because they are afraid of backlash with a rubber centered coupling.

A “U-joint” with bearing slide axis would last a little longer, or if you can float the motor as they try to do by leaving the mounting screw loose but then you can still have a Z axis back lash issue.

A little more time spent on the engineering of the motor mounting scheme would have better MTBF (mean time between failure).

But what do I know about any of this stuff?


Thanks, Drew. I notice the replacement couplers are the rubber-centered type; the metal one was from my v1 machine s/n 52, which has been run heavily for over 2-1/2 years, so I'm not too upset by the life.