@Steppenleguan said in Independent dual z axis with endstops - z homing not working:

@knuxvomica no they don´t.
Current state: G28 homing failed , and nothing happens
Before with a homez.g: The axis lifts 5mm, moves down then passes! the endstops and hits my frame when I don´t emergency stop...

As you can see I am using the M564 command to test the axis movements in advance (which works fine) but obviously I don´t have any homing , i.e. no printing possible

M564 H0 ;move without homing

@Phaedrux said in Independent dual z axis with endstops - z homing not working:

Please post your full config.g
Homing Z should be as simple as a G1 H1 Z move to move the z axis such that the endstops are hit.

You need G1 H1 Z-700 at the end of your homeall.g to home the Z axis. The same would be needed in homez.g

@alankilian I might have found the problem.
I checked the resistances of the 5V signal wires
from the breakout board to the stepper drivers again and I found one cable that has infinite resistance.
It seems like it is one of the dir+- cables. So that would explain why the motor is running but cannot change its director.

At first I was expecting it to be the crimps or the connectors, but it appears that even with new crimps the cable is corrupted.

I'm checking in again in the evening and take a new cable, measure the resistances and hope that this solves to problem.

@craigylad86 said in Loss use of z axis.:

The z axis started to play up by missing some steps and eventually juddering up down and in opposite directions as I was controling.

That's typically caused either by excessive friction of the axis; or binding (most common when there are multiple Z motors and they have got out of sync), or setting the Z acceleration (M201) or maximum speed (M203) too high.

It could also be caused by a bad connection between the stepper motor and the Duet, so that only one phase of the motor is being driven. If that's the case then you may get "phase may be disconnected" warnings from RRF.

Ah yes, depending on how you've started a printer profile in Cura it may include some speed limiting commands for marlin based printers. Best to delete those lines.

A leadscrew with a 2mm pitch will help you in more ways than one, if you use a 2mm pitch you can utilise a full step number at multiple layer heights. And the added bonus is that the bed won't drop, the price of leadscrews means its a very cheap (but extremely worthwhile) upgrade

alright, great, thanks!
(can I mark this as solved?)

Good point, I am just curious about the possibilities is all, even thou it might over complicate things.