<p>I'm transforming my Anet A8 printer to Raspberry Pi driven using <a href="https://github.com/Nikolay-Kha/PyCNC" rel="nofollow noreferrer">PyCNC</a>. Things seem to look promising so far apart from the Z motor doing nothing but making screaming-like sound when supposed to be moving (In <code>pycnc</code> enter command <code>z10</code>).</p>

<p>I was playing with the <a href="https://github.com/Nikolay-Kha/PyCNC/blob/master/cnc/config.py" rel="nofollow noreferrer">config</a>, changed the Z related velocity and step values. Didn't see any difference.</p>

<p>When I start <code>pycnc</code> and enter command <code>g28</code> (all axis home) the Z needs some help... <a href="https://photos.app.goo.gl/YuCuJ44ojv6wtaqF8" rel="nofollow noreferrer">Here is a video.</a></p>

<p>Has anyone got experience in PyCNC? Or any idea?</p>

CC BY-SA 4.0
2019-09-19T07:29:52.213Z
That sounds like you're trying to use too much acceleration (the *really* relevant thing in kinematics rather than velocity), but it seems you can only set that for all axes at the same time.
towe
CC BY-SA 4.0
2019-09-19T08:04:35.020Z
@towe Nice spot in the FW of PyCNC! For reference in Marlin default config.: `#define DEFAULT_MAX_ACCELERATION      { 3000, 3000, 100, 10000 }` for X, Y, Z and E respectively.
0scar
CC BY-SA 4.0
2019-09-19T15:02:04.877Z
Thank you both. I have managed to make the Z motor work by adjusting the `STEPPER_PULSES_PER_MM_Z` to 50. I'm not sure what this exactly is. ‍♂️
haxpanel
<anet-a8><stepper><raspberry-pi><python><pycnc>
PyCNC - Z steppers screaming
haxpanel
# PyCNC - Z steppers screaming

(Asked by: username_0 on 2019-09-19)

I'm transforming my Anet A8 printer to Raspberry Pi driven using [PyCNC](https://github.com/Nikolay-Kha/PyCNC). Things seem to look promising so far apart from the Z motor doing nothing but making screaming-like sound when supposed to be moving (In `pycnc` enter command `z10`).

I was playing with the [config](https://github.com/Nikolay-Kha/PyCNC/blob/master/cnc/config.py), changed the Z related velocity and step values. Didn't see any difference.

When I start `pycnc` and enter command `g28` (all axis home) the Z needs some help... [Here is a video.](https://photos.app.goo.gl/YuCuJ44ojv6wtaqF8)

Has anyone got experience in PyCNC? Or any idea?

**Tags:** anet-a8, stepper, raspberry-pi, python, pycnc

> **Comments:**
> **username_1**: That sounds like you're trying to use too much acceleration (the *really* relevant thing in kinematics rather than velocity), but it seems you can only set that for all axes at the same time.  
> **username_2**: @username_1 Nice spot in the FW of PyCNC! For reference in Marlin default config.: `#define DEFAULT_MAX_ACCELERATION      { 3000, 3000, 100, 10000 }` for X, Y, Z and E respectively.  
> **username_0**: Thank you both. I have managed to make the Z motor work by adjusting the `STEPPER_PULSES_PER_MM_Z` to 50. I'm not sure what this exactly is. ‍♂️  

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## 0 answers

