How do I move one Z motor independently of the others?
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I have a core xy so there are 4 Z motors that move the gantry in the Z. My inductive probe is not triggering consistenly across the bed so I want to manually level the gantry by just using a piece of paper under the nozzle at each of the 4 corners of the bed. How do I move one Z motor independently of the others?
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You can map the driver you want to control to a new axis U and then control that axis. You should define all the other parameters for that U axis as well. When done you can recombine it to Z.
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@phaedrux Hmmm, seems rather involved but I think I can work it out. Will it let motors P5-P8 participate in more than one axis?
So like P5 can be part of Z and also U? -
@erice555 If P5 can only be part of one axis then I'll need to completely different config.g files. Will it switch config files without a restart?
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It will probably be easier to have a macro to switch between mappings.
This technique is used for indepent homing using micro switches. Here's an example.
https://duet3d.dozuki.com/Guide/Independent+Z+motors+and+endstop+switches+in+RRF2/18
Not that example is for RRF2 but the principles of remapping drives is the same.
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Edit: never mind the below. With some searching I figured out a G92 sets the homed state and then allows me to move the 'axis'. So far so good.
@phaedrux I made a good start on this but once I create my 4 independent axis, I don't have a way to home them. How can I fake them out that they are homed so I can move them?
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@erice555 I seem to have this working. One can have a motor involved in more than one axis so I just have 4 extra axis a,b,c,d and adjust them as I need. Then I go straight into a print. It still homes Z and all just as it did, so I am golden. Thank you.
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G92 is an option, or you can use G1 H2 movements to force the motor to move even if not homed.
abcd are usually reserved for rotational axis, so you may wish to use UVWZ instead.
glad you got it working
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@erice555 use the built-in levelling mechanism. See https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors.
