New Build MK4S - right Z-axis motor "slipping" causing z-axis calibration to fail.
After being amazed by the quality of the Mini+, I decided it was time to add an MK4S and MMU3. I followed through the build guide as well as IIfti's fantastic video series.
Upon firing it up, it passed the first few tests but fails the Z-axis calibration test. I noticed it really vibrating a lot as it moved up and down when it was performing the test. Then it descended to the bed and smashed the nozzle into it. Not a great result.
I made sure it is on the latest firmware after reading past posts of calibration issues (admittedly those reports are 5.x days).
Since the Z-axis test was sending the nozzle into the bed (again), I decided to just use the Z-axis manual control. It became very obvious that the left z-motor is moving slower than the right one, resulting in the x-axis assembly chattering as it moves. I double checked that the threaded rod wasn't binding at all in the x-axis carriage on the left and the right. When I disconnect the trapezoidal nut and let the x-carriage move freely, it doesn't bind at all on the z-axis motor threaded rods.
I then started fiddling with the left threaded rod and notice that I can easily stop the threaded rod from moving when tell the printer to move the Z-axis. It's like the threaded rod "slipping" in the motor.
When I try to stop the right threaded rod there is no chance I can stop it. It has too much torque as you'd expect.
So, I'm assuming I was sent a bad left z-axis motor/rod?
However, the next morning as I was filming this video demonstrating the problem , I noticed the right motor was easily 140 degrees hot! The printer hand't been doing anything but sitting there turned on for an hour or so. (No motion of any motors.)
So I seem to have one motor that is "slipping" and another that is incredibly hot?Can anyone give me some advice?
Have I dome something wrong that could be causing this?
RE:
I would double check the connections inside the xBuddy box. Unplug the two Z-axis connectors. Look for loose wires or pins on the connectors. Plug them back in carefully, making sure they’re fully seated. If the problem persists, you probably have a bad Z motor. Most likely the one on the left, but it could be either or both. I’d ask to have them both replaced.
MK4S/MMU3
RE: New Build MK4S - right Z-axis motor "slipping" causing z-axis calibration to fail.
Thanks for the reply. I checked the ZL connector and as I popped it out, a quarter of it fell off and a pin is loose. So the left motor connector is definitely a major problem.