# 3 independant Z-Endstops

**URL:** <https://klipper.discourse.group/t/3-independant-z-endstops/115>\
**Category:** General Discussion\
**Created:** [April 11, 2021, 6:43am UTC](https://klipper.discourse.group/t/3-independant-z-endstops/115 "2021-04-11T06:43:23Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\
**Post date:** [April 11, 2021, 6:43am UTC](https://klipper.discourse.group/t/3-independant-z-endstops/115/1 "2021-04-11T06:43:23Z")

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I’m thinking of a printer design, which has 3 more or less independent Bed-Z-Axes on linear rails driven by a belt. When stepper power is cut, the axes will likely start dropping.

Would it be possible in Klipper to go the following approach:

- Do a “reference move” towards Z-Max
- Hit 3 Endstops independently on Z-Max on each Z-Axis
- Do the actual homing move against a single Z-Min

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**Author:** ![koconnor](https://avatars.discourse-cdn.com/v4/letter/k/aca169/32.png) [@koconnor](https://klipper.discourse.group/u/koconnor)\
**Post date:** [April 11, 2021, 4:50pm UTC](https://klipper.discourse.group/t/3-independant-z-endstops/115/2 "2021-04-11T16:50:37Z")

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I’m not really sure what you’re asking. If you are asking if it’s possible to home to Z max, but use a separate (more accurate) switch to set the Z position, then it may be possible to do that today, but it’s complex.

One can define the Z-max endstop switches as regular endstops in the `[stepper_z]` config sections. Then define the z min switch in a `[probe]` config section. Then after homing, one can issue a `PROBE` command to move towards and trigger the z-min switch. One can then use a macro to call `SET_GCODE_OFFSET Z=...` to set the Z position using that z-min switch. Yes - this solution is complex and it wont work if a bed probe is also needed. Maybe it gives some ideas though.

Cheers,  
-Kevin

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**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\
**Post date:** [April 12, 2021, 11:30am UTC](https://klipper.discourse.group/t/3-independant-z-endstops/115/3 "2021-04-12T11:30:48Z")

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Many thanks for coming back to me.

I guess your answer fits pretty well.  
The idea is / was to have 3 Z-Towers with linear rails and driven by a belt. These 3 Z-Towers should carry a magnetically mounted heat bed.

To have this idea working properly, I would have to ensure that these 3 towers are perfectly synchronized, which cannot be secured once the motor power is turned off.

So I was thinking of a “pre home” move, i.e. hitting 3 endstops at the base of the towers to have them synchronized and then the “real” homing towards Z-min.

Unfortunately the idea apparently does not work out since I do not want to omit the possibility to use a bed probe.

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**Author:** ![EddyMI3D](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/eddymi3d/32/1981_2.png) [@EddyMI3D](https://klipper.discourse.group/u/EddyMI3D)\
**Post date:** [September 4, 2024, 11:28am UTC](https://klipper.discourse.group/t/3-independant-z-endstops/115/4 "2024-09-04T11:28:55Z")

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Closed on September 4, 2024, 11:28am UTC