<p>The surface defects you describe is caused by Z-wobble. Basically this leads back in a defect in the Z axis gantry where X and/or Y movements are transferred into the print head. This can be cause by:</p>

<ul>
<li>a damaged nut, </li>
<li>lead screw not straight, </li>
<li>stick-slip, </li>
<li>binding, </li>
<li>lead screw out of alignment with the coupler, </li>
<li>lead screw touching the stepper shaft in the coupler, </li>
<li>the Z guide (at the other side of the X-axis arm; the one without the extruder mounted on it) has too much friction of the wheels on the profile,</li>
<li>play on the carriage, </li>
<li>lead screw should be the same distance from the extrusion profile from top to bottom, </li>
<li>etc.</li>
</ul>

<p></p>

CC BY-SA 4.0
2020-03-22T14:11:57.013Z
...and possibly a cummulative rounding error
Trish
CC BY-SA 4.0
2020-03-22T14:13:39.817Z
@Trish Didn't you write a previous answer on that? Please add an answer or link to it.
0scar
CC BY-SA 4.0
2020-03-22T14:17:47.013Z
It was discussed in https://3dprinting.stackexchange.com/questions/10986/how-to-calculate-the-proper-layer-height-multiples
Trish
CC BY-SA 4.0
2020-03-22T08:09:32.303Z
2020-03-22T14:01:20.903Z
2020-03-22T14:01:20.903Z
0scar
<p>I'm having an odd effect in my prints. There is some sort of surface problem that seems to be evenly spaced in z. I tried to tighten my belts, the print speed is 75 mm/s using a 32 bit board, on an Ender 3 Pro.</p>

<p>Any recommendations?</p>

<p><a href="https://i.sstatic.net/xXC2K.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/xXC2K.jpg" alt="enter image description here"></a></p>

<creality-ender-3><surface>
Equally spaced surface flaws
user1543042
# Equally spaced surface flaws

(Asked by: username_0 on 2020-03-22)

I'm having an odd effect in my prints. There is some sort of surface problem that seems to be evenly spaced in z. I tried to tighten my belts, the print speed is 75 mm/s using a 32 bit board, on an Ender 3 Pro.

Any recommendations?

[![enter image description here](https://i.sstatic.net/xXC2K.jpg)](https://i.sstatic.net/xXC2K.jpg)

**Tags:** creality-ender-3, surface


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## 1 answers

### Answer by username_1 on 2020-03-22. Score: 1

The surface defects you describe is caused by Z-wobble. Basically this leads back in a defect in the Z axis gantry where X and/or Y movements are transferred into the print head. This can be cause by:

* a damaged nut,
* lead screw not straight,
* stick-slip,
* binding,
* lead screw out of alignment with the coupler,
* lead screw touching the stepper shaft in the coupler,
* the Z guide (at the other side of the X-axis arm; the one without the extruder mounted on it) has too much friction of the wheels on the profile,
* play on the carriage,
* lead screw should be the same distance from the extrusion profile from top to bottom,
* etc.

> **Comments:**
> **username_2**: ...and possibly a cummulative rounding error  
> **username_1**: @username_2 Didn't you write a previous answer on that? Please add an answer or link to it.  
> **username_2**: It was discussed in https://3dprinting.stackexchange.com/questions/10986/how-to-calculate-the-proper-layer-height-multiples  

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