<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.stack.imgur.com/BLeFU.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/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.stack.imgur.com/0Z3YX.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/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.stack.imgur.com/arA1s.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/arA1s.jpg" alt="enter image description here" /></a></p>
<p><a href="https://i.stack.imgur.com/wpxT3.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/wpxT3.jpg" alt="enter image description here" /></a></p>

[{'answer_id': 15941, 'author': 'Snympi', 'author_id': 7470, 'author_profile': 'https://3dprinting.stackexchange.com/users/7470', 'pm_score': 1, 'selected': False, 'text': '<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>\n<p>I print 3\xa0mm clearance fit holes on my Prusa MK3S, meant to fit on 3.00\xa0mm (measured with a digital caliper) stainless steel shafts. The printed parts are from Fusion 360 models, with 3\xa0mm holes by design, converted to STL and then sliced and printed with 0.2\xa0mm layer height. The holes are very close to 3.0\xa0mm and out by 0.05-0.1\xa0mm.</p>\n<p>The solution was to make adjustments in Fusion. I left the model with the hole size as 3\xa0mm but then use the Offset Face command on the inside of the extruded hole to make it slightly larger with the required tolerance.</p>\n<p><a href="https://i.stack.imgur.com/OaMCs.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OaMCs.png" alt="enter image description here" /></a></p>\n<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>\n<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>\n'}, {'answer_id': 15944, 'author': 'Trish', 'author_id': 8884, 'author_profile': 'https://3dprinting.stackexchange.com/users/8884', 'pm_score': 2, 'selected': False, 'text': '<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>\n<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>\n<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>\n<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>\n<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>\n<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>\n'}]
['https://3dprinting.stackexchange.com/questions/15863', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/27334/']