Welcome to the SeeMeCNC Community

I recently built a Rostock V3 and, after a brief bed level issue, had printed successfully for a couple days. Then during a print, the Z axis began only moving down and crashed the head into the bed.

I tried pressing the Z axis stepper wires firmer into the Rambo board, and now all the axis motors are only stepping down. But sometimes when I shake the wires, one or two of the axis (I've seen all three do this) will work for a few seconds.

I've filmed what happens when I manually adjust the Z height. At the beginning of the video the X axis is working correctly, but it stops working part of the way through the video. https://youtu.be/30lDH-utQ1Q

Any ideas how to troubleshoot?

I bet your z height is set to zero (or nearly so ) when at the home (top) position. Reset your z-zero point and then re-run a g29.

g.

Hi Geneb, I confirmed Z was set correctly. G29 fails because the stepper motors won't move up into the home position.

You've got a wiring problem then.

g.

did someone found a solution?

Sounds like you've got a problem with your endstop wiring. You can troubleshoot them by following the steps in this guide: https://seemecnc.zendesk.com/hc/en-us/a ... ing-Issues