Z homing problem

Dear All,

I have had problems with Z homing:
Z home causes the motor to only move upwards a small amount in the + direction
but will intermittently home sometimes

Can I run the Z motors unjoined to the board using extra Z-motor header on the Sanguinolu?

I didn't have Z problems using RAMPS but the same problem on
both (pre-asssembled, tested) Sanguinolu boards which I prefer to
use on this Prusa

Thank you for your help
Simon

Assuming your homing Z minus, the endstop switch is probably bad or set incorrectly in the firmware.
What homing does is move until it hts the end stop reverse off it and move back to the stop, if the endstop is always on then you just get the reverse part of that.
You can probably still print because the default in most firmwares is to ignore endstops while printing.

Thanks for the reply Polygonhell,
Yesterday I tried connecting the 2 Z motors
unjoined to the 2 connectors on Z, which didn't
Work as the motors spun unevenly or only one
spun
Then I clipped the wires of the motors down
considerably and reconnected in parallel to a
different terminal block (I paired the colours )
For the first time Z homed correctly and moved in both
+ and - , but I don't really understand why?

Best
Simon

I have a Z homing issue as well: G28 Z or using Z Home on Pronterface doesn't do anything. When carriage hits Z end stop the motors don't stop but M119 is showing the Z end stop has changed to high so unsure what is happening

Mendel 90
Sanguinolulu
Marlin
Top Z Endstop
Both Z motors wired together (probably different wire lengths) into single connector to sanguinolulu

Everything else is working fine and I can control either via an Arduino terminal window or Pronterface (X, Y movement and homing, Bed and head heating, extrusion)

Z doesn't seem to want to move negative as well as not wanting to home but sometimes movement seems fine.

Anyone got any suggestions?

Hi Logrod


have had any luck?

did you try clipping the motor leads and changing
to a smaller size terminal block, I didn't solder just twisted and put heat
shrink on the cut cables

Hi Gnomadix,

Not done anything since yesterday but going to try Z axis movement with other axies disconnected and then try X or Y connected to Z header / and/or Z connected to X/Y header to see if there is any difference (I know the steps/mm is different for diff axies in config.h but if I'm only using G1 or G28 I don't think it should be a problem)

My Z motor cables are soldered together, heat shrunk and then taken to a single header.