<p>Besides offsetting the <strong>clearances</strong> you want into models, you can and should also calibrate your printer to <strong>compensate for included holes</strong> - because often inner holes are solved to be smaller than actually designed out of necessity.</p>
<p>However, the option can <em>also</em> be used to fix problems that stem from the slicing and printing itself, and thus offers to fix some problems that are endemic to your setup or where you can't easily fix the model by setting an offset to create the wanted clearances in it.</p>
<p>In Ultimaker <strong>Cura</strong>, the option for this fix is called <code>Hole horizontal expansion</code> since <a href="https://community.ultimaker.com/topic/32187-ultimaker-cura-46-released/" rel="nofollow noreferrer">4.6 in April 2020</a>, which only affects internal perimeters as I know from testing.</p>
<p><strong>SuperSlicer</strong>, a PrusaSlicer branch offers <code>hole_XY_compensation</code>, though I can't quite pinpoint the time when it was added. I guesstimate sometime before <a href="https://github.com/supermerill/SuperSlicer/commit/151ea0a39f94d383fdf17802e4e52e787a7bae46" rel="nofollow noreferrer">October 2020</a>.</p>
<p><strong>PrusaSlicer</strong> offers <code>XY size compensation</code>, which does affect outer perimeters. A hole-only is requested almost since that option was available the first time. An attempt to implement a hole-only compensation again appears to be <a href="https://github.com/prusa3d/PrusaSlicer/issues/4561" rel="nofollow noreferrer">worked on since mid-2020.</a> It seems that in the beginning of March some implementation has been tested.</p>
<p>The first work for such a function <a href="https://manual.slic3r.org/troubleshooting/dimension-errors" rel="nofollow noreferrer">was tried by <strong>Slic3r</strong></a> before PrusaSlicer was started on, using an <a href="https://reprap.org/mediawiki/index.php?title=ArcCompensation&amp;action=history" rel="nofollow noreferrer">Arc-compensation formula</a> in at latest 2009, but the function proved to be overcompensating. As Prusa-Slicer is a <em>fork</em> of Slic3r, some of this work might remain in the code.</p>

CC BY-SA 4.0
2021-03-25T10:12:10.733Z
2021-03-25T10:55:32.870Z
2021-03-25T10:55:32.870Z
Trish
<p>This seems like a tolerance press fit problem and similar to what you will find if you try the same using normal machining operations on a lathe or milling machine.</p>
<p>I print 3 mm clearance fit holes on my Prusa MK3S, meant to fit on 3.00 mm (measured with a digital caliper) stainless steel shafts. The printed parts are from Fusion 360 models, with 3 mm holes by design, converted to STL and then sliced and printed with 0.2 mm layer height. The holes are very close to 3.0 mm and out by 0.05-0.1 mm.</p>
<p>The solution was to make adjustments in Fusion. I left the model with the hole size as 3 mm but then use the Offset Face command on the inside of the extruded hole to make it slightly larger with the required tolerance.</p>
<p><a href="https://i.sstatic.net/OaMCs.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/OaMCs.png" alt="enter image description here" /></a></p>
<p>In my case, an offset of 0.05 provided a nice press fit, and 0.1 offset allowed the shaft to closely fit in the hole but loose enough to rotate.</p>
<p>I suggest you create a simple model with a number of holes designed to be the same size and then use different Offset Face numbers to dial in what you need. That way you get to learn what to expect from your printer and its accuracy.</p>

CC BY-SA 4.0
2021-03-25T03:24:23.970Z
2021-03-25T03:30:26.023Z
2021-03-25T03:30:26.023Z
Snympi
<p>I uploaded a 3D object for <a href="https://lerdagiovanni.wixsite.com/kauda/stl-files" rel="nofollow noreferrer">this project</a> to Fusion 360 and printed it out straightforward:</p>
<p><a href="https://i.sstatic.net/BLeFU.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/BLeFU.png" alt="enter image description here" /></a></p>
<p>Yet its middle hole is too small for the stepper motor (<a href="https://www.omc-stepperonline.com/nema-17-stepper-motor/" rel="nofollow noreferrer">Nema 17 Stepper-M</a>) I am using so I wanted to increase its tolerance before reprinting it.</p>
<p>So, I followed the <a href="https://www.youtube.com/watch?v=SigAE7GG9vs&amp;ab_channel=TylerBeckofTech%26Espresso" rel="nofollow noreferrer">tutorial by Tyler Beck of Tech</a> who lead me to drawings:</p>
<p><a href="https://i.sstatic.net/0Z3YX.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/0Z3YX.png" alt="enter image description here" /></a></p>
<p>I was wondering if doing a drawing (sketch in Fusion 360) was sufficient to expect the shaft of the step motor to go through?</p>
<p>Here are the gear and the shaft before I add the drawing constraints:</p>
<p><a href="https://i.sstatic.net/arA1s.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/arA1s.jpg" alt="enter image description here" /></a></p>
<p><a href="https://i.sstatic.net/wpxT3.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/wpxT3.jpg" alt="enter image description here" /></a></p>

CC BY-SA 4.0
2021-03-14T21:54:08.993Z
When you say "its middle hole is too small for the step motor" are you talking about fractions of a millimeter or several percent smaller?
agarza
CC BY-SA 4.0
2021-03-15T08:02:20.887Z
Is this a Fusion problem or a problem with your printer. I would expect the latter to be the culprit.
0scar
CC BY-SA 4.0
2021-03-15T09:31:55.203Z
@agarza fractions of millimeter, I would say one millimeter max. I will upload a photo soon.
Revolucion for Monica
CC BY-SA 4.0
2021-03-15T21:18:39.940Z
are you sure that that is not a print error?
Trish
CC BY-SA 4.0
2021-03-15T21:37:00.853Z
A digital caliper is a very useful tool to use with 3d printing. Sometimes when printing, smaller features like holes don't come out exactly the size you need, and the caliper will let you measure what change is needed in the drawing. Or you can just guess at the needed change and print another one at the new size and if that doesn't fit you will have a better guess for the next iteration.
Andrew Morton
<fusion360><dimensional-accuracy><press-fit>
Are Fusion 360 drawings sufficient to design and enforce tolerance in a hole of a solid?
Revolucion for Monica
# Are Fusion 360 drawings sufficient to design and enforce tolerance in a hole of a solid?

(Asked by: username_0 on 2021-03-14)

I uploaded a 3D object for [this project](https://lerdagiovanni.wixsite.com/kauda/stl-files) to Fusion 360 and printed it out straightforward:

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

Yet its middle hole is too small for the stepper motor ([Nema 17 Stepper-M](https://www.omc-stepperonline.com/nema-17-stepper-motor/)) I am using so I wanted to increase its tolerance before reprinting it.

So, I followed the [tutorial by Tyler Beck of Tech](https://www.youtube.com/watch?v=SigAE7GG9vs&ab_channel=TylerBeckofTech%26Espresso) who lead me to drawings:

[![enter image description here](https://i.sstatic.net/0Z3YX.png)](https://i.sstatic.net/0Z3YX.png)

I was wondering if doing a drawing (sketch in Fusion 360) was sufficient to expect the shaft of the step motor to go through?

Here are the gear and the shaft before I add the drawing constraints:

[![enter image description here](https://i.sstatic.net/arA1s.jpg)](https://i.sstatic.net/arA1s.jpg)

[![enter image description here](https://i.sstatic.net/wpxT3.jpg)](https://i.sstatic.net/wpxT3.jpg)

**Tags:** fusion360, dimensional-accuracy, press-fit

> **Comments:**
> **username_1**: When you say "its middle hole is too small for the step motor" are you talking about fractions of a millimeter or several percent smaller?  
> **username_2**: Is this a Fusion problem or a problem with your printer. I would expect the latter to be the culprit.  
> **username_0**: @username_1 fractions of millimeter, I would say one millimeter max. I will upload a photo soon.  
> **username_3**: are you sure that that is not a print error?  
> **username_4**: A digital caliper is a very useful tool to use with 3d printing. Sometimes when printing, smaller features like holes don't come out exactly the size you need, and the caliper will let you measure what change is needed in the drawing. Or you can just guess at the needed change and print another one at the new size and if that doesn't fit you will have a better guess for the next iteration.  

---

## 2 answers

### Answer by username_3 on 2021-03-25. Score: 2

Besides offsetting the **clearances** you want into models, you can and should also calibrate your printer to **compensate for included holes** - because often inner holes are solved to be smaller than actually designed out of necessity.

However, the option can *also* be used to fix problems that stem from the slicing and printing itself, and thus offers to fix some problems that are endemic to your setup or where you can't easily fix the model by setting an offset to create the wanted clearances in it.

In Ultimaker **Cura**, the option for this fix is called `Hole horizontal expansion` since [4.6 in April 2020](https://community.ultimaker.com/topic/32187-ultimaker-cura-46-released/), which only affects internal perimeters as I know from testing.

**SuperSlicer**, a PrusaSlicer branch offers `hole_XY_compensation`, though I can't quite pinpoint the time when it was added. I guesstimate sometime before [October 2020](https://github.com/supermerill/SuperSlicer/commit/151ea0a39f94d383fdf17802e4e52e787a7bae46).

**PrusaSlicer** offers `XY size compensation`, which does affect outer perimeters. A hole-only is requested almost since that option was available the first time. An attempt to implement a hole-only compensation again appears to be [worked on since mid-2020.](https://github.com/prusa3d/PrusaSlicer/issues/4561) It seems that in the beginning of March some implementation has been tested.

The first work for such a function [was tried by **Slic3r**](https://manual.slic3r.org/troubleshooting/dimension-errors) before PrusaSlicer was started on, using an [Arc-compensation formula](https://reprap.org/mediawiki/index.php?title=ArcCompensation&action=history) in at latest 2009, but the function proved to be overcompensating. As Prusa-Slicer is a *fork* of Slic3r, some of this work might remain in the code.


---

### Answer by username_5 on 2021-03-25. Score: 1

This seems like a tolerance press fit problem and similar to what you will find if you try the same using normal machining operations on a lathe or milling machine.

I print 3 mm clearance fit holes on my Prusa MK3S, meant to fit on 3.00 mm (measured with a digital caliper) stainless steel shafts. The printed parts are from Fusion 360 models, with 3 mm holes by design, converted to STL and then sliced and printed with 0.2 mm layer height. The holes are very close to 3.0 mm and out by 0.05-0.1 mm.

The solution was to make adjustments in Fusion. I left the model with the hole size as 3 mm but then use the Offset Face command on the inside of the extruded hole to make it slightly larger with the required tolerance.

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

In my case, an offset of 0.05 provided a nice press fit, and 0.1 offset allowed the shaft to closely fit in the hole but loose enough to rotate.

I suggest you create a simple model with a number of holes designed to be the same size and then use different Offset Face numbers to dial in what you need. That way you get to learn what to expect from your printer and its accuracy.


---

