CORE One

<p><strong>MK4 to MK4S upgrade <br /></strong></p>
<p>The current lead time is <strong>1-2 weeks </strong>for both xLCD versions. </p>
<p> </p>
<h3>Original Prusa CORE One shipping table</h3>
<table class="table" style="border-collapse: collapse; height: 963.875px; border-style: ridge; width: 100%;" border="1">
<tbody>
<tr style="height: 60.875px;">
<td style="height: 60.875px; width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center;">
<h4>  Order date</h4>
</td>
<td style="height: 60.875px; width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center;">
<h4>Estimated shipping</h4>
</td>
</tr>
<tr style="height: 33px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 33px;">
<p>  19.11.2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 33px;">
<p>from 31.1.2025</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>  20.11.2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 7 (starts February 10, 2025)</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>  21.11.2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 7 (starts February 10, 2025)</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>  22.11.2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 8 (starts February 17, 2025)</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>  23.11.2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 8 (starts February 17, 2025)</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>  24.11.2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 8 (starts February 17, 2025)</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>W48 2024 - from November 25, 2024 </p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 9 (starts February 24, 2025)</p>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>W49 2024 - from December 2, 2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>from week 10 (starts March 3, 2025) </p>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>W50 2024 - from December 9, 2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>from week 11 (starts March 10, 2025)</p>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>W51 2024 - from December 16, 2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>from week 11 (starts March 10, 2025)</p>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>W52 2024 -  from December 23, 2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>from week 12 (starts March 17, 2025)</p>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>W1 2025 - from December 30, 2024</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>from week 12 (starts March 17, 2025)</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>W2 2025 - from January 6, 2025</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 13 (starts March 24, 2025)</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>W3 2025 - from January 13, 2025</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 13 (starts March 24, 2025)</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>W4 2025 - from January 20, 2025</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 13 (starts March 24, 2025)</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>W5 2025 - from January 27, 2025</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>from week 14 (starts March 31, 2025)</p>
</td>
</tr>
</tbody>
</table>
<h3><span style="font-size: 20px;">Current lead time estimates for new orders</span></h3>
<p><span style="color: #e67e23;"><strong>Updated: January 28th, 2025 </strong></span></p>
<p><em>The dates are only an estimation at the date of update, specified above, and rely on the actual</em> production. <em>We're doing our best but please be aware that it can shift for the lead time products. We will update here and on the product pages accordingly.</em></p>
<p>The lead time estimate applies to standalone products, other products in the order may increase the lead time.</p>
<p>If you've ordered a product in a bundle, the lead time of the order is set based on the product in the bundle with the longest lead time.</p>
<p></p>
<table class="table" style="border-collapse: collapse; height: 930.875px; border-style: ridge; width: 100%;" border="1">
<tbody>
<tr style="height: 60.875px;">
<td style="height: 60.875px; width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center;">
<h4>Product</h4>
</td>
<td style="height: 60.875px; width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center;">
<h4>Lead time</h4>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p><strong>MK4 to MK4S upgrade</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>MK3.9 to MK3.9S upgrade</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>MK3S/+ to MK4S upgrade</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>3-4 weeks</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>MK3S/+ to MK3.9S upgrade</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>MK3S/S+ to MK3.5S</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>Original Prusa MK4S</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>1 week</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>Original Prusa MK4S kit</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>Original Prusa XL<br /></strong>(Prusa XL Assembled 5-toolhead 3D Printer)</p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>1-2 weeks<br /><strong>(2-3 weeks)</strong></p>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p><strong>Original Prusa MMU3 upgrade kit<br />(for MK3.9/S &amp; MK4/S)<br /></strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p><strong>Original Prusa MMU2S to MMU3 upgrade<br />(for MK3.9/S &amp; MK4/S)</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p><strong>Original Prusa MMU3 assembled unit<br />(MK3.9/S &amp; MK4/S)</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 72px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p><strong>Original Prusa MMU3 assembled unit<br />(MK3S+ &amp; MK3.5/S)</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 72px;">
<p>1-2 week</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>Original Prusa XL Enclosure</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>Original Prusa MINI Enclosure</strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>1-2 weeks</p>
</td>
</tr>
<tr style="height: 51px;">
<td style="width: 48.3436%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p><strong>Original Prusa MK Enclosure </strong></p>
</td>
<td style="width: 51.6564%; border-style: dotted; border-width: 1px; text-align: center; height: 51px;">
<p>1-2 weeks</p>
</td>
</tr>
</tbody>
</table>
<p>You can find your order shipping date in the order detail section in our shop.</p>
<div class="note-callout">All products purchased in our <a href="https://shop.prusa3d.com/">online store</a> are currently being shipped from the<strong> Czech Republic, </strong>a member state of the <strong>European Union, customs charges may apply for shipments to countries outside of the EU!</strong> Please see our advisory article <a href="http://help.prusa3d.com/article/vat-value-added-tax-customs-fees_1505#orders-outside-eu">here</a>.</div>

Shipping information

<p>Each Original Prusa printer is shipped with a bundle of sample G-codes. These G-codes are tested and tailored specifically for your printer model and can be used to see the printer's capabilities or troubleshoot.</p>
<p>Find your printer in the table and download the zip archive. The model geometry (.stl/.3mf) and the presliced version (.gcode) are included.</p>
<div class="tip-callout">You can find all our sample prints, including the printable parts of our printers, on our <a href="https://www.printables.com/@Prusa3D/collections/">Printables page</a>.</div>
<h2>Original Prusa FFF Series</h2>
<table class="striped" style="width: 100%; height: 639.687px;">
<tbody>
<tr style="height: 21.3333px;">
<td style="width: 33.1288%; height: 21.3333px; text-align: left;"><strong>Printer model</strong></td>
<td style="width: 16.9325%; text-align: left; height: 21.3333px;"><strong>Printer type</strong></td>
<td style="width: 25.0307%; height: 21.3333px; text-align: left;"><strong>3D models</strong></td>
<td style="width: 25.0307%; text-align: left; height: 21.3333px;"><strong>G-codes</strong></td>
</tr>
<tr style="height: 20.8889px;">
<td style="width: 33.1288%; height: 20.8889px;">CORE One</td>
<td style="width: 16.9325%; height: 20.8889px;">FFF</td>
<td style="width: 25.0307%; height: 20.8889px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/COREOne_Sample_Models.zip">link</a></td>
<td style="width: 25.0307%; height: 20.8889px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/COREOne_Sample_Gcodes.zip">link</a></td>
</tr>
<tr style="height: 27.1944px;">
<td style="width: 33.1288%; height: 27.1944px;">MK4S/MK3.9S</td>
<td style="width: 16.9325%; height: 27.1944px;">FFF</td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK4S-MK39S-3dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK4S-MK3.9S-gcodes.zip">link</a></td>
</tr>
<tr style="height: 27.1944px;">
<td style="width: 33.1288%; height: 27.1944px;">MK4/MK3.9</td>
<td style="width: 16.9325%; height: 27.1944px;">FFF</td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK4-MK39-3dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK4-MK39-gcodes.zip">link</a>*</td>
</tr>
<tr style="height: 28.7986px;">
<td style="width: 33.1288%; height: 28.7986px;">MK3.5/S</td>
<td style="width: 16.9325%; height: 28.7986px;">FFF</td>
<td style="width: 25.0307%; height: 28.7986px;">TBA</td>
<td style="width: 25.0307%; height: 28.7986px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK3.5-S_Sample_Gcodes.zip">link</a></td>
</tr>
<tr style="height: 36px;">
<td style="width: 33.1288%; height: 36px;">MK3S+</td>
<td style="width: 16.9325%; height: 36px;">FFF</td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK3family-3dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK3S%2B_MK3S_MK3-gcodes.zip">link</a></td>
</tr>
<tr style="height: 36px;">
<td style="width: 33.1288%; height: 36px;">MK3S</td>
<td style="width: 16.9325%; height: 36px;">FFF</td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK3family-3dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK3S%2B_MK3S_MK3-gcodes.zip">link</a></td>
</tr>
<tr style="height: 27.1944px;">
<td style="width: 33.1288%; height: 27.1944px;">MK3</td>
<td style="width: 16.9325%; height: 27.1944px;">FFF</td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK3family-3dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK3S%2B_MK3S_MK3-gcodes.zip">link</a></td>
</tr>
<tr style="height: 36px;">
<td style="width: 33.1288%; height: 36px;">MINI+</td>
<td style="width: 16.9325%; height: 36px;">FFF</td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MINI%2B_MINI-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MINI%2B_MINI-gcodes.zip">link</a></td>
</tr>
<tr style="height: 27.1944px;">
<td style="width: 33.1288%; height: 27.1944px;">MINI</td>
<td style="width: 16.9325%; height: 27.1944px;">FFF</td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MINI%2B_MINI-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MINI%2B_MINI-gcodes.zip">link</a></td>
</tr>
<tr style="height: 27.1944px;">
<td style="width: 33.1288%; height: 27.1944px;">XL 1T</td>
<td style="width: 16.9325%; height: 27.1944px;">FFF</td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/XL-1T-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/XL-1T-gcodes.zip">link</a></td>
</tr>
<tr style="height: 36px;">
<td style="width: 33.1288%; height: 36px;">XL 2T</td>
<td style="width: 16.9325%; height: 36px;">FFF</td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/XL-2T-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/XL-2T-gcodes.zip">link</a></td>
</tr>
<tr style="height: 36px;">
<td style="width: 33.1288%; height: 36px;">XL 5T</td>
<td style="width: 16.9325%; height: 36px;">FFF</td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/XL-5T-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/XL-5T-gcodes.zip">link</a></td>
</tr>
<tr style="height: 36px;">
<td style="width: 33.1288%; height: 36px;">MMU3 &amp; MK4</td>
<td style="width: 16.9325%; height: 36px;">FFF</td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU3-MK4-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU3-MK4-gcodes.zip">link</a></td>
</tr>
<tr style="height: 27.1944px;">
<td style="width: 33.1288%; height: 27.1944px;">MMU3 &amp; MK4S</td>
<td style="width: 16.9325%; height: 27.1944px;">FFF</td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU3-MK4S-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU3-MK4S-gcodes.zip">link</a></td>
</tr>
<tr style="height: 27.1111px;">
<td style="width: 33.1288%; height: 27.1111px;">MMU3 &amp; MK3S/+</td>
<td style="width: 16.9325%; height: 27.1111px;">FFF</td>
<td style="width: 25.0307%; height: 27.1111px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU3-MK3S-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 27.1111px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU3-MK3S-gcodes.zip">link</a></td>
</tr>
<tr style="height: 36px;">
<td style="width: 33.1288%; height: 36px;">MMU2S &amp; MK3S/+</td>
<td style="width: 16.9325%; height: 36px;">FFF</td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU2S_MMU2-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK3S%2B_MK3S_MMU2S-gcodes.zip">link</a></td>
</tr>
<tr style="height: 27.1944px;">
<td style="width: 33.1288%; height: 27.1944px;">MMU2S &amp; MK2.5S</td>
<td style="width: 16.9325%; height: 27.1944px;">FFF</td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU2S_MMU2-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK25S_MMU2S-gcodes.zip">link</a></td>
</tr>
<tr style="height: 36px;">
<td style="width: 33.1288%; height: 36px;">MMU2 &amp; MK3</td>
<td style="width: 16.9325%; height: 36px;">FFF</td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU2S_MMU2-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK3_MMU2-gcodes.zip">link</a></td>
</tr>
<tr style="height: 27.1944px;">
<td style="width: 33.1288%; height: 27.1944px;">MMU2 &amp; MK2.5</td>
<td style="width: 16.9325%; height: 27.1944px;">FFF</td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU2S_MMU2-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 27.1944px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK25_MMU2-gcodes.zip">link</a></td>
</tr>
<tr style="height: 36px;">
<td style="width: 33.1288%; height: 36px;">MMU1 &amp; MK2</td>
<td style="width: 16.9325%; height: 36px;">FFF</td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MMU1-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 36px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/MK2MMU-gcodes.zip">link</a></td>
</tr>
</tbody>
</table>
<p><em>*The archive includes G-codes for both MK4 and MK3.9 printers. G-codes are sliced for Input Shaper and older non-Input Shaper firmware. To print the Input Shaper G-codes, please make sure your printer is running <a href="https://help.prusa3d.com/downloads">firmware 5.0.0 or newer</a>.</em></p>
<h2>Original Prusa SLA Series</h2>
<table class="striped" style="width: 100%; height: 73px;">
<tbody>
<tr style="height: 21px;">
<td style="width: 33.1288%; height: 21px; text-align: left;"><strong>Printer model</strong></td>
<td style="width: 16.9325%; text-align: left; height: 21px;"><strong>Printer type</strong></td>
<td style="width: 25.0307%; height: 21px; text-align: left;"><strong>3D models</strong></td>
<td style="width: 25.0307%; text-align: left; height: 21px;"><strong>G-codes</strong></td>
</tr>
<tr style="height: 21px;">
<td style="width: 33.1288%; height: 21px;">Original Prusa SL1S</td>
<td style="width: 16.9325%; height: 21px;">MSLA</td>
<td style="width: 25.0307%; height: 21px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/SL1S-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 21px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/SL1S-gcodes.zip">link</a></td>
</tr>
<tr style="height: 21px;">
<td style="width: 33.1288%; height: 21px;">Original Prusa SL1</td>
<td style="width: 16.9325%; height: 21px;">MSLA</td>
<td style="width: 25.0307%; height: 21px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/SL1-3Dmodels.zip">link</a></td>
<td style="width: 25.0307%; height: 21px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/SL1-gcodes.zip">link</a></td>
</tr>
</tbody>
</table>
<h2>Prusa Pro FFF Series</h2>
<table class="striped" style="width: 100%; height: 31px;">
<tbody>
<tr style="height: 21px;">
<td style="width: 33.1288%; height: 21px; text-align: left;"><strong>Printer model</strong></td>
<td style="width: 16.9325%; text-align: left; height: 21px;"><strong>Printer type</strong></td>
<td style="width: 25.0307%; height: 21px; text-align: left;"><strong>3D models</strong></td>
<td style="width: 25.0307%; text-align: left; height: 21px;"><strong>G-codes</strong></td>
</tr>
<tr style="height: 10px;">
<td style="width: 33.1288%; height: 10px;">Prusa Pro HT90</td>
<td style="width: 16.9325%; height: 10px;">FFF</td>
<td style="width: 25.0307%; height: 10px;">TBA</td>
<td style="width: 25.0307%; height: 10px;"><a href="https://www.prusa3d.com/downloads/SampleModelsGcodes/HT90-gcodes.zip">link</a></td>
</tr>
</tbody>
</table>
<p> </p>


Sample G-codes

<p>On the <strong>Prusa CORE One</strong>, <strong>Original Prusa MK4/S</strong>, <strong>MK3.9/S</strong>, <strong>MK3.5/S</strong>, and <strong>XL</strong>, the firmware is flashed using a USB flash drive. This is valid for all ways of firmware updating. </p>
<h3>Offline USB Drive procedure</h3>
<ol>
<li>Download the latest firmware for your printer and extract it (zip file) on your computer
<ul>
<li><a href="https://help.prusa3d.com/tag/core-one">Prusa CORE One</a></li>
<li><a href="https://help.prusa3d.com/tag/mk4s">Original Prusa MK4S</a></li>
<li><a href="https://help.prusa3d.com/tag/mk4">Original Prusa MK4</a></li>
<li><a href="https://help.prusa3d.com/tag/mk3-9s">Original Prusa MK3.9S</a></li>
<li><a href="https://help.prusa3d.com/tag/mk3-9">Original Prusa MK3.9</a></li>
<li><a href="https://help.prusa3d.com/tag/mk3-5s">Original Prusa MK3.5S</a></li>
<li><a href="https://help.prusa3d.com/tag/mk3-5">Original Prusa MK3.5</a></li>
<li><a href="https://help.prusa3d.com/tag/xl">Original Prusa XL</a></li>
</ul>
</li>
<li>Make sure the USB flash drive doesn't contain any previous firmware (.bbf file)</li>
<li>Copy the new .bbf file to the root directory of a USB flash drive (Not within a folder).</li>
<li>Insert the USB flash drive and push the reset button<strong>.</strong> The bootloader will automatically compare the installed version with the one on the drive and, if it is newer, will automatically offer you to flash it. </li>
<li>Confirm the update by selecting the "FLASH" button and pressing the knob. </li>
</ol>
<p>If you need to downgrade the firmware or re-flash the same firmware, follow this guide: <a href="http://help.prusa3d.com/article/how-to-downgrade-firmware-mk4-s-mk3-9-s-mk3-5-s-xl_725930">How to downgrade firmware</a>.</p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/12/bea8afeb237e8fbf20569f4fb0b05180_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;">
<p><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/fd92b9aa013388cb_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="How to update firmware (CORE One, MK4/S, MK3.9/S, MK3.5/S, XL)" alt="" width="395" height="296" loading="lazy" /></p>
</td>
</tr>
</tbody>
</table>
<h3>OTA (Over-The-Air) firmware update</h3>
<p>If your printer is connected to <a href="https://help.prusa3d.com/article/prusa-connect-and-prusalink-explained_302608"><strong>Prusa Connect</strong></a>, an over-the-air firmware update is also possible. </p>
<div class="tip-callout">It is still necessary to have a USB drive connected to the printer! </div>
<p>Prusa Connect checks the printer’s firmware version and offers you an option to remotely update it if a newer version is available. Click on the orange arrow icon to open a new window, with the option to transfer the new firmware file to the USB drive inserted in the printer. </p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/89fe9b29dc6ebf11e2f94715e062bcdd.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="How to update firmware (CORE One)" alt="" width="500" height="500" loading="lazy" /></p>
<h3>Factory Reset</h3>
<p>If you do a <strong>hard</strong> <a href="http://help.prusa3d.com/article/factory-reset-core-one-mk4-s-mk3-9-s-mk3-5-s-mini-xl_421206"><strong>Factory Reset</strong></a>, it is necessary to insert a USB drive with a firmware file. This firmware file is installed in the printer, so this can be used as a way to update the firmware. </p>


How to update firmware (CORE One, MK4/S, MK3.9/S, MK3.5/S, XL)

<p>The Original Prusa FFF printers and upgrades use a screw(s) with a spring(s) to provide tension between the filament and the filament pulley. It is important to have this tension correct. If too loose the pulley will not be able to "grab" the filament, while if it is too tight the extruder motor can overexert itself and even start grinding the filament. With the exception of the MK2/S and MMU1, the correct tension remains the same across all of our printers. </p>
<div class="note-callout">When printing flexible filaments (TPU/TPE) you want the screw even looser than what is depicted here. Please see <a href="http://help.prusa3d.com/article/flexible-materials_2057">Flexible materials</a> for more information.</div>
<h3>CORE One, MK4/S, MK3.9, XL</h3>
<p>The Prusa <strong>CORE One</strong>, and the Original Prusa <strong>MK4/S</strong>, <strong>MK3.9/S</strong>, and <strong>XL</strong> have two idler screws, that are inserted into the Idler Nut. The Idler Nut keeps the Idler, the part that includes the two driven gears, in place. <strong>The <span style="color: #e67e23;">tips</span> of the <span style="color: #236fa1;">screws</span> must be aligned with the front surface of the Idler Nut</strong>. </p>
<p style="text-align: center;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/e5e9007aa7f7e4ebc09ee326677c2868_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Idler screw tension REVIEW" alt="" width="600" height="450" loading="lazy" /><em>Prusa CORE One</em></p>
<table style="border-collapse: collapse; width: 100%; height: 314px; border-style: none;" border="0">
<tbody>
<tr style="height: 296px;">
<td style="width: 48.805%; height: 296px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/7f3d3c9d26dca5b135940240addcdcae_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Idler screw tension" alt="" width="1519" height="1139" loading="lazy" /></td>
<td style="width: 48.9057%; height: 296px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/c70184370f0c657419a8d850bbe6cbbb_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Idler screw tension" alt="" width="1519" height="1137" loading="lazy" /></td>
</tr>
<tr style="height: 18px;">
<td style="width: 48.805%; height: 18px; text-align: center;"><em>Original Prusa MK4S, MK3.9S</em></td>
<td style="width: 48.9057%; height: 18px; text-align: center;"><em>Original Prusa MK4, MK3.9</em></td>
</tr>
</tbody>
</table>
<p> </p>
<table style="border-collapse: collapse; width: 100%; border-style: none;" border="0">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/b74f048af6f2bd91b2e38d745b418355_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Idler screw tension" alt="" width="1519" height="1139" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/81c688544f80a8d33e6e25fb939a06bc_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Idler screw tension" alt="" width="1519" height="1013" loading="lazy" /></td>
</tr>
<tr>
<td style="width: 48.8562%; text-align: center;"><em>Original Prusa MK4 with MMU3-modified extruder</em></td>
<td style="width: 48.8562%; text-align: center;"><em>Original Prusa XL</em></td>
</tr>
</tbody>
</table>
<p>On the Original Prusa XL, the dwarf-cover-door prevents access to adjusting the idler tension screws. </p>
<p>On single-head XL, it is possible to gain access by <span style="color: #e67e23;"><strong>rotating the dwarf-cover-door</strong></span>. On dual-head and five-head XL, with the tool in the <strong>parked</strong> position, <span style="color: #b96ad9;"><strong>loosen the M3x12 bolt</strong></span> to remove the dwarf-cover-door. </p>
<table style="border-collapse: collapse; width: 100%; border-style: none;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/05/f8d3940f26dd204ea309f6bad12a697a_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Hotend Heater Overcurrent #17322" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/05/c9f81ea9acb8359339663218c7536d58_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Hotend Heater Overcurrent #17322" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>MK2.5S/MK3S/MK3S+/MK3.5/MK3.5S</h3>
<p><strong>The idler screw should be about flush to protruding 0.5 -1 mm with the plastic part</strong> when the filament is not loaded.</p>
<table style="border-collapse: collapse; width: 100%; height: 314px;" border="0">
<tbody>
<tr style="height: 296px;">
<td style="width: 48.805%; height: 296px;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu.jpg" alt="" width="500" height="375" loading="lazy" /></td>
<td style="width: 48.9057%; height: 296px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/ee967edc46e92f22_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/ee967edc46e92f22_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/ee967edc46e92f22_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/ee967edc46e92f22_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/ee967edc46e92f22_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/ee967edc46e92f22_painted-1536x1152.jpeg 1536w" alt="" width="400" height="300" loading="lazy" /></td>
</tr>
<tr style="height: 18px;">
<td style="width: 48.805%; height: 18px; text-align: center;"><em>Original Prusa MK3S</em></td>
<td style="width: 48.9057%; height: 18px; text-align: center;"><em>Original Prusa MK3S+</em></td>
</tr>
</tbody>
</table>
<h3>MMU3 unit</h3>
<p>Both Idler tension screws should be adjusted so that the top of the screw head is flush or slightly above the top surface of the idler-body, as a default setting.</p>
<table style="border-collapse: collapse; width: 100%;" border="0">
<tbody>
<tr>
<td style="width: 48.7895%;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/03/5558cf0ae35a537a_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Idler screw tension" width="1600" height="1200" loading="lazy" /></td>
<td style="width: 48.7895%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/03/13d08877b40afea6_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Idler screw tension" alt="" width="1600" height="1200" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>MMU2S unit</h3>
<p>The MMU2S requires a slightly different extruder but also has 1 idler-screw on the left side of the extruder, like the picture above. Roughly the same tension should be applied but it should only be adjusted as a part of the <a href="http://help.prusa3d.com/article/ir-filament-sensor-calibration-mmu3-mmu2s_2245">IR filament sensor calibration</a>.</p>
<p>In addition to the screw on the extruder, the MMU2S unit itself has two tension screws on top (<span style="color: #2dc26b;">green arrows</span> left picture), applying pressure to the filament upon load/unload. <strong>These should be slightly below the surface of the plastic part (about 1 millimeter) when the filament is not loaded to the nozzle</strong> (right picture<strong>).</strong></p>
<table style="border-collapse: collapse; width: 100%;" border="0">
<tbody>
<tr>
<td style="width: 48.7895%;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/b5a4d8f48bb56027.jpg" width="500" /></td>
<td style="width: 48.7895%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2021/06/381b6af53da89771_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2021/06/381b6af53da89771_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/06/381b6af53da89771_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/06/381b6af53da89771_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/06/381b6af53da89771_painted-768x576.jpeg 768w" alt="" width="400" height="300" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>MINI/MINI+</h3>
<p>The Original Prusa MINI/+ has its idler screw on the bottom of the extruder, located on the Z-axis extrusion. This too should be about flush with the plastic, when the filament is not loaded.</p>
<table style="border-collapse: collapse; width: 100%; margin-left: auto; margin-right: auto;" border="0">
<tbody>
<tr>
<td style="width: 48.805%;"><em><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/0000da5fe874fa5a_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/0000da5fe874fa5a_painted-600x400.jpeg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/0000da5fe874fa5a_painted-800x533.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/0000da5fe874fa5a_painted-300x200.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/0000da5fe874fa5a_painted-768x512.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/0000da5fe874fa5a_painted-1536x1023.jpeg 1536w" alt="" width="400" height="266" loading="lazy" /></em></td>
<td style="width: 48.9057%;"><em><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/idlerscrw.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/idlerscrw-600x400.jpg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/idlerscrw-800x533.jpg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/idlerscrw-300x200.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/idlerscrw-768x512.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/idlerscrw-1536x1024.jpg 1536w" alt="" width="400" height="267" loading="lazy" /></em></td>
</tr>
</tbody>
</table>
<h3>MK3/MK2.5</h3>
<p>This extruder design has two idler screws. <strong>The head of the screw should be about flush to sticking out 1 - 1.5 mm when a filament is loaded.</strong></p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/MK3.jpg" alt="" width="500" height="375" loading="lazy" /></p>
<h3>MK2S</h3>
<p>The Original Prusa MK2S had a different extruder design. It has two screws, where the length of the springs <strong>should be circa 13 mm when tightened</strong>. After some use, it is ok to tighten them a little bit more, but the two screws must be equal.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/e45b5f6259af9be1_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/e45b5f6259af9be1_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/e45b5f6259af9be1_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/e45b5f6259af9be1_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/e45b5f6259af9be1_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/e45b5f6259af9be1_painted-1536x1152.jpeg 1536w" alt="" width="500" height="375" loading="lazy" /></p>

Idler screw tension

<p>Every Original Prusa printer has a unique serial number assigned to it. This is found on a silver sticker on every machine and is also hardcoded to the main controller board. Serial numbers issued before November 2021 start with "<em>CZPX</em>", while after November 2021 we introduced a new format starting with "SN". All serials are registered in our internal database and they allow us to confirm your printer as genuine.</p>
<div class="tip-callout">For some printer models, placing the serial sticker on the frame is part of the <a href="http://help.prusa3d.com/guide/8-electronics-assembly_174100#175963">assembly process</a>!</div>
<div class="note-callout">The best way to reference your printer is the <strong>order number</strong> you received when purchasing the printer. This can be found on the invoice or in <a href="https://www.prusa3d.com/account/orders/">your order-history in the eshop</a>.</div>
<h3>Prusa CORE One</h3>
<p>A label is found on the back of the printer, between the PSU and the xBuddy board. </p>
<p><img decoding="async" loading="lazy" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/8303de23e031fc59e1d4fe762ba855b2.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Original Prusa Serial Number" alt="" width="600" height="450" /></p>
<h3>Original Prusa MK-series </h3>
<div>A label can be found on the back of the frame above the PSU, or on the rear plate of the printer.</div>
<div> </div>
<table style="border-collapse: collapse; width: 99.99%;" border="0">
<tbody>
<tr>
<td style="width: 48.7906%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/04/9aac28c3506b361e6375f78ac5abcde4_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Original Prusa Serial Number REVIEW" alt="" width="400" height="300" loading="lazy" /></td>
<td style="width: 48.7906%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/09/7bbdbf77e40293215c0a8c48aa58fc6f.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Original Prusa Serial Number" alt="" width="400" height="300" loading="lazy" /></td>
</tr>
<tr>
<td style="width: 48.7906%; text-align: center;"><em>Original Prusa MK-series until 2022</em></td>
<td style="width: 48.7906%; text-align: center;"><em>Original Prusa MK-series from 2023</em></td>
</tr>
</tbody>
</table>
<h3>Original Prusa MINI &amp; MINI+</h3>
<div>A label is found on the Z-axis extrusion (circled in red), on the right side.</div>
<div> </div>
<div><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/1ac6991c2990d506_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/1ac6991c2990d506_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/1ac6991c2990d506_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/1ac6991c2990d506_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/1ac6991c2990d506_painted-800x600.jpeg 800w" alt="" width="1600" height="450" loading="lazy" /></div>
<div> </div>
<h3>Original Prusa XL</h3>
<p>The Original Prusa XL may have one or two silver stickers. If the printer has <strong>one sticker</strong>, the serial number will be on the <strong>bottom left</strong>. If the printer has <strong>both </strong>the silver sticker on the bottom and on the top left, the one you should use is the one on the <strong>top</strong>. In either case, the label will show the text 'Original PRUSA XL'. </p>
<div class="warning-callout">If the bottom sticker shows Original PRUSA PDU, the printer serial number sticker is on the top left of the printer.</div>
<table style="border-collapse: collapse; width: 100%;" border="0">
<tbody>
<tr>
<td style="width: 50.0596%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/09/37ecaf46e9f477c1f5c173619f1004ae.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Original Prusa Serial Number" alt="" width="400" height="267" loading="lazy" /></td>
<td style="width: 50.0596%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/09/a9ef93e4bd2e8e2a453e29b02e4cf257.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Original Prusa Serial Number" alt="" width="400" height="300" loading="lazy" /></td>
</tr>
<tr>
<td style="width: 50.0596%; text-align: center;"><em>Top printer serial number</em></td>
<td style="width: 50.0596%; text-align: center;"><em>Bottom printer serial number</em></td>
</tr>
</tbody>
</table>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/01/28f5cbf1395eb564088cf9aa3dc18d28_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Original Prusa Serial Number" alt="" width="600" height="400" loading="lazy" /></p>
<h3>Original Prusa SL1 &amp; SL1S</h3>
<div>A label is found on the back (circled in red), in the bottom left. </div>
<div> </div>
<div><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/b6b660768dd4f994_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/b6b660768dd4f994_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/b6b660768dd4f994_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/b6b660768dd4f994_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/b6b660768dd4f994_painted-800x600.jpeg 800w" alt="" width="600" height="450" loading="lazy" /></div>
<div> </div>
<h3>Original Prusa Enclosure</h3>
<p>The label can be found on the side of the PSU holder.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/09/9429b9afb9f83ee803a88081940ac71a.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Original Prusa Serial Number" alt="" width="700" height="467" loading="lazy" /></p>
<h3>Hardcoded serial number</h3>
<div>This requires a special application and commands, dependent on the printer, to extract. Nothing proprietary, but the procedure is rather advanced. If you really need to get the serial number this way, please email <a href="http://help.prusa3d.com/article/customer-support_2287">Customer support</a>. </div>


Original Prusa Serial Number

Prusa CORE One (assembled)

Assembly manuals

Basic calibration

All information you need to know to learn how to calibrate your 3D printer to achieve perfect prints.

Calibration

Printer features

FAQs and other useful information you might be interested in before or after making your purchase at shop.prusa3d.com

General Information

Basic overview of your 3D printer and it's features, plus general Prusa Research info.

About your printer

Printer maintenance

In this section, you can find material guides, printer troubleshooting and general info about using your printer.

Using the printer

QR Error codes

Printer troubleshooting

Description of how to recognize and solve common problems, especially hardware and electronics related.

Troubleshooting

1. Introduction

2. Unpacking the printer

3. Mounting the xLCD

4. Calibration & First run

Manual changelog

Print Quality Troubleshooting

<p>The Prusa CORE One, and the Original Prusa XL, MK4/S, MK3.9/S are equipped with a <a href="http://help.prusa3d.com/article/loadcell-mk4-s-mk3-9-s-xl_401253">loadcell</a>. Thanks to this component, starting from firmware 6.0.0, the printer can detect whether the filament is stuck and not moving, for example when the nozzle is clogged. </p>
<p>If this is detected, the print pauses and the printer shows the message: "<strong>Stuck filament detected. The filament seems to be stuck. Please unload it from the extruder and load it again</strong>." </p>
<p>Once the <strong>unload </strong>button is pressed, the printer unloads the filament. After this, it prompts filament loading and resumes the print. </p>
<div class="tip-callout">It is important to note that detecting stuck filament is possible only inside the Nextruder, as pressure builds up from the nozzle to the upper part of the Nextruder. However, if your filament is tangled on the spool, there will be no internal pressure, just outside tension, which the loadcell won't recognize.</div>
<div>Stuck filament detection won't be possible on MK3.5 and MINI/MINI+ as they aren't equipped with the loadcell sensor.</div>
<p style="text-align: center;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/04/e884e31f8ae9e52017bacbeb8fcd544e.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Stuck filament detection #13101 (MK4) #21101 (MK3.9)" alt="" width="500" height="333" loading="lazy" /><em>Screenshot from the Original Prusa MK4</em></p>


Stuck filament detection #31101 (CORE One) #26101 (MK4S) #13101 (MK4) #27101 (MK3.9S) #21101 (MK3.9) #17108 (XL)

<p>During normal function, your printer saves statistics, calibration data, and personalized settings, even after it is turned off. If you feel like you changed settings that have negatively affected your 3D printer, you can always revert to factory default values and try again. </p>
<div class="note-callout">Doing a factory reset will clear statistics data, like total printing time and filament use.</div>
<h3>How to factory reset</h3>
<p>Factory Reset can be done via <em>LCD Menu -&gt; Settings -&gt; System -&gt; Factory Reset</em>. </p>
<p>Starting firmware 4.6.1 there are two options:</p>
<ul>
<li><strong>Reset Settings &amp; Calibrations</strong> - this option deletes all changes done by the user and reverts the system to its original state. For most of the cases, this is a sufficient method. Technically speaking only the EEPROM with user stored data is deleted. Once, the reset is done, the printer will boot to language selection, followed by the calibration wizard.</li>
<li><strong>Hard reset (USB with FW needed)</strong> - due to the complex partition layout, the firmware stores its settings not only in the EEPROM but also on the XFLASH. In some edge cases, it might be necessary to delete both of these. Once this reset is done, the user must insert a USB drive with <a href="http://help.prusa3d.com/article/how-to-update-firmware-core-one-mk4-s-mk3-9-s-mk3-5-s-xl_453086">firmware</a> as some parts of the XFLASH will be created again from scratch.</li>
</ul>
<h3>Flashing firmware</h3>
<p>If you see any inconsistent behavior we recommend also flashing the firmware.</p>
<ul>
<li><a href="http://help.prusa3d.com/article/how-to-update-firmware-core-one-mk4-s-mk3-9-s-mk3-5-s-xl_453086">CORE One, MK4/S, MK3.9/S, MK3.5/S, XL</a></li>
<li><a href="http://help.prusa3d.com/article/firmware-updating-mini-mini_124784">MINI/+</a></li>
</ul>
<p>A factory reset followed by flashing the firmware and recalibrating will resolve most firmware issues you may encounter. </p>


Factory reset (CORE One, MK4/S, MK3.9/S, MK3.5/S, MINI/+, XL)

<h3>What happened?</h3>
<p>The <strong>Prusa CORE One</strong>, and the <strong>Original Prusa MK4/S</strong>, <strong>MK3.9/S</strong> are equipped with a <strong>loadcell</strong>, which detects whether the nozzle is close enough to the steel sheet for printing and prevents damage from the nozzle digging into the steel sheet. </p>
<p>The printer firmware expects a measurement sample from the loadcell to occur within a specified time. In case this does not happen, the printer will show the message <strong>"There was a timeout while waiting for measurement sample, please repeat the action."</strong></p>
<p>Error name: Loadcell Timeout</p>
<p>Error code: #31528 (CORE One) #26528 (MK4S) #13528 (MK4) #27528 (MK3.9S) #21528 (MK3.9)</p>
<h3>How to fix it? </h3>
<h4>A visual inspection</h4>
<div class="warning-callout">Before you start, make sure:</p>
<ul>
<li>the filament is unloaded from the extruder</li>
<li>the printer is turned OFF and unplugged from electricity</li>
<li>the hotend and the heatbed are cooled down to ambient temperature</li>
</ul>
</div>
<p>Access the right side of the LoveBoard, where the loadcell cable is connected. To remove the side LoveBoard cover, on CORE One loosen two<span style="color: #000000;"> <span style="color: #236fa1;"><strong>M3x6 bolts</strong></span></span>, on MK4/S and MK3.9/S loosen one <span style="color: #843fa1;"><strong>M3x10 bolt</strong></span>. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/c565b5d3a12f4e32b712cc273759d4e8_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Timeout REVIEW #31528 (CORE One) #26528 (MK4S) #13528 (MK4) #27528 (MK3.9S) #21528 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/94e576c7396585eb388df6fd136a8ec8_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<p>Once accessed, locate the <span style="color: #e67e23;"><strong>loadcell connector</strong></span> and cable, and check for any loose cable, disconnected cable, or visible damage. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;">
<p style="text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/04/98f9151af765084ab2be69a52d63f20c_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></p>
</td>
<td style="width: 48.8562%; text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/3c492d1b5efc9c403a26bd3c455c2ea7_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h4><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/5e54e7bdd6fef88f48746c4095106a4f.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="500" height="375" loading="lazy" /></h4>
<h4>Re-test the loadcell</h4>
<div class="warning-callout">Do not manipulate or touch the printer unless the instructions on the printer screen prompt you to do so.</div>
<div>
<p>Navigate to <em>LCD Menu -&gt; Control -&gt; Calibrations &amp; Tests -&gt; Loadcell Test</em> to initiate a loadcell test. </p>
<p>During the test, you will be asked to tap the nozzle at a specific time, and a progress bar shown on the screen is filled, depending on the pressure applied to the loadcell. If the bar is not filled or is filled irregularly, please contact our <a href="http://help.prusa3d.com/article/customer-support_2287">customer support</a>. </p>
<div class="tip-callout">Tapping of the nozzle can be done with a finger, as well as with a hard object. </div>
<table style="border-collapse: collapse; width: 100%; border-style: none;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/e03a4297a772916ed43b160f9300a4b6_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/3226ee7326e5f8c4057eb46f4d9f8a55_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>Loadcell white pad - visual check </h3>
<div class="warning-callout">Ensure to have the <strong>PG-assembly-adapter</strong> before continuing with the following procedure. If you do not have it, you can print it using the below files, depending on the printer you will use: <br /><a href="https://files.printables.com/media/prints/451501/stls/4104840_55cb7d05-d1f6-4cca-8159-db9ac9f62942/pg-assembly-adapter-mk4-r1.stl">PG-assembly-adapter printed with MK4/S</a><br /><a href="https://files.printables.com/media/prints/451501/stls/4240522_6fa05937-693e-4282-8dce-a98d3e93fd5f/pg-assembly-adapter-mk3-r2.stl">PG-assembly-adapter printed with MK3/S/+</a></div>
<ol>
<li>If any filament is loaded, unload the filament, then wait for the printer to fully cool down. After that, turn the printer off.</li>
<li>Remove the PG-case, together with the PG-ring, gearbox, and main plate. Remove all of these parts in one piece. </li>
</ol>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/1c7df54642bb103d2a7d3ed01b41cbff_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/67c593556671a61a79c52036477d3454.jpg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<ol start="3">
<li>The top part of the loadcell is now visible and has a white pad attached to it. Without touching the white pad, check it for damage. </li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/4f0b8b4b2de761bec7c838efa8152ca9_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="500" height="375" loading="lazy" /></p>
<ol start="4">
<li>Reassemble the block of PG-case, PG-ring, gearbox, and main plate. In case the parts are not in one block, follow the dedicated steps from the Nextruder <a href="http://help.prusa3d.com/attachment/ltlznibfugnpwtwy-jpg_272">assembly manual</a>, depending on your printer version. </li>
<li>Perform the <a href="http://help.prusa3d.com/article/gearbox-alignment-core-one-mk4-s-mk3-9-s_465779">gearbox alignment</a>. </li>
</ol>
</div>


Loadcell Timeout #31528 (CORE One) #26528 (MK4S) #13528 (MK4) #27528 (MK3.9S) #21528 (MK3.9)

<h3>What happened?</h3>
<p>The <strong>Prusa CORE One</strong>, and the <strong>Original Prusa MK4/S</strong>, <strong>MK3.9/S</strong> are equipped with a <strong>loadcell</strong>, which detects whether the nozzle is close enough to the steel sheet for printing and prevents damage from the nozzle digging into the steel sheet. </p>
<p>The loadcell measures the amount of force that the nozzle applies to the steel sheet. In case the measured value is abnormally high, or undefined, the printer will show the message <strong>"Loadcell measured an infinite or undefined load value."</strong></p>
<p>Error name: Loadcell Measure Failed</p>
<p>Error code: #31526 (CORE One) #26526 (MK4S) #13526 (MK4) #27526 (MK3.9S) #21526 (MK3.9)</p>
<h3>How to fix it? </h3>
<h4>A visual inspection</h4>
<div class="warning-callout">Before you start, make sure:</p>
<ul>
<li>the filament is unloaded from the extruder</li>
<li>the printer is turned OFF and unplugged from electricity</li>
<li>the hotend and the heatbed are cooled down to ambient temperature</li>
</ul>
</div>
<p>Access the right side of the LoveBoard, where the loadcell cable is connected. To remove the side LoveBoard cover, on CORE One loosen two<span style="color: #000000;"> <span style="color: #236fa1;"><strong>M3x6 bolts</strong></span></span>, on MK4/S and MK3.9/S loosen one <span style="color: #843fa1;"><strong>M3x10 bolt</strong></span>. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/c565b5d3a12f4e32b712cc273759d4e8_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Measure Failed REVIEW #31526 (CORE One) #26526 (MK4S) #13526 (MK4) #27526 (MK3.9S) #21526 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/94e576c7396585eb388df6fd136a8ec8_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<p>Once accessed, locate the <span style="color: #e67e23;"><strong>loadcell connector</strong></span> and cable, and check for any loose cable, disconnected cable, or visible damage. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;">
<p style="text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/04/98f9151af765084ab2be69a52d63f20c_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></p>
</td>
<td style="width: 48.8562%; text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/3c492d1b5efc9c403a26bd3c455c2ea7_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h4><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/5e54e7bdd6fef88f48746c4095106a4f.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="500" height="375" loading="lazy" /></h4>
<h4>Re-test the loadcell</h4>
<div class="warning-callout">Do not manipulate or touch the printer unless the instructions on the printer screen prompt you to do so.</div>
<div>
<p>Navigate to <em>LCD Menu -&gt; Control -&gt; Calibrations &amp; Tests -&gt; Loadcell Test</em> to initiate a loadcell test. </p>
<p>During the test, you will be asked to tap the nozzle at a specific time, and a progress bar shown on the screen is filled, depending on the pressure applied to the loadcell. If the bar is not filled or is filled irregularly, please contact our <a href="http://help.prusa3d.com/article/customer-support_2287">customer support</a>. </p>
<div class="tip-callout">Tapping of the nozzle can be done with a finger, as well as with a hard object. </div>
<table style="border-collapse: collapse; width: 100%; border-style: none;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/e03a4297a772916ed43b160f9300a4b6_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/3226ee7326e5f8c4057eb46f4d9f8a55_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>Loadcell white pad - visual check </h3>
<div class="warning-callout">Ensure to have the <strong>PG-assembly-adapter</strong> before continuing with the following procedure. If you do not have it, you can print it using the below files, depending on the printer you will use: <br /><a href="https://files.printables.com/media/prints/451501/stls/4104840_55cb7d05-d1f6-4cca-8159-db9ac9f62942/pg-assembly-adapter-mk4-r1.stl">PG-assembly-adapter printed with MK4/S</a><br /><a href="https://files.printables.com/media/prints/451501/stls/4240522_6fa05937-693e-4282-8dce-a98d3e93fd5f/pg-assembly-adapter-mk3-r2.stl">PG-assembly-adapter printed with MK3/S/+</a></div>
<ol>
<li>If any filament is loaded, unload the filament, then wait for the printer to fully cool down. After that, turn the printer off.</li>
<li>Remove the PG-case, together with the PG-ring, gearbox, and main plate. Remove all of these parts in one piece. </li>
</ol>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/1c7df54642bb103d2a7d3ed01b41cbff_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/67c593556671a61a79c52036477d3454.jpg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<ol start="3">
<li>The top part of the loadcell is now visible and has a white pad attached to it. Without touching the white pad, check it for damage. </li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/4f0b8b4b2de761bec7c838efa8152ca9_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="500" height="375" loading="lazy" /></p>
<ol start="4">
<li>Reassemble the block of PG-case, PG-ring, gearbox, and main plate. In case the parts are not in one block, follow the dedicated steps from the Nextruder <a href="http://help.prusa3d.com/attachment/ltlznibfugnpwtwy-jpg_272">assembly manual</a>, depending on your printer version. </li>
<li>Perform the <a href="http://help.prusa3d.com/article/gearbox-alignment-core-one-mk4-s-mk3-9-s_465779">gearbox alignment</a>. </li>
</ol>
</div>


Loadcell Measure Failed #31526 (CORE One) #26526 (MK4S) #13526 (MK4) #27526 (MK3.9S) #21526 (MK3.9)

<h3>What happened?</h3>
<p>The <strong>Prusa CORE One</strong>, and the <strong>Original Prusa MK4/S</strong>, <strong>MK3.9/S</strong> are equipped with a <strong>loadcell</strong>, which detects whether the nozzle is close enough to the steel sheet for printing and prevents damage from the nozzle digging into the steel sheet. </p>
<p>During a selftest, the loadcell is tested. The loadcell can also be tested at any time through the printer menu. If the loadcell calibration is not done, or the printer does not recognize that it has been done, it will show the message: <strong>"Loadcell calibration is not finished. Finish the calibration first."</strong></p>
<p>Error name: Loadcell Not Calibrated</p>
<p>Error code: #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)</p>
<h3>How to fix it? </h3>
<h4>A visual inspection</h4>
<div class="warning-callout">Before you start, make sure:</p>
<ul>
<li>the filament is unloaded from the extruder</li>
<li>the printer is turned OFF and unplugged from electricity</li>
<li>the hotend and the heatbed are cooled down to ambient temperature</li>
</ul>
</div>
<p>Access the right side of the LoveBoard, where the loadcell cable is connected. To remove the side LoveBoard cover, on CORE One loosen two<span style="color: #000000;"> <span style="color: #236fa1;"><strong>M3x6 bolts</strong></span></span>, on MK4/S and MK3.9/S loosen one <span style="color: #843fa1;"><strong>M3x10 bolt</strong></span>. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/c565b5d3a12f4e32b712cc273759d4e8_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/94e576c7396585eb388df6fd136a8ec8_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<p>Once accessed, locate the <span style="color: #e67e23;"><strong>loadcell connector</strong></span> and cable, and check for any loose cable, disconnected cable, or visible damage. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;">
<p style="text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/04/98f9151af765084ab2be69a52d63f20c_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></p>
</td>
<td style="width: 48.8562%; text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/3c492d1b5efc9c403a26bd3c455c2ea7_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h4><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/5e54e7bdd6fef88f48746c4095106a4f.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="500" height="375" loading="lazy" /></h4>
<h4>Re-test the loadcell</h4>
<div class="warning-callout">Do not manipulate or touch the printer unless the instructions on the printer screen prompt you to do so.</div>
<div>
<p>Navigate to <em>LCD Menu -&gt; Control -&gt; Calibrations &amp; Tests -&gt; Loadcell Test</em> to initiate a loadcell test. </p>
<p>During the test, you will be asked to tap the nozzle at a specific time, and a progress bar shown on the screen is filled, depending on the pressure applied to the loadcell. If the bar is not filled or is filled irregularly, please contact our <a href="http://help.prusa3d.com/article/customer-support_2287">customer support</a>. </p>
<div class="tip-callout">Tapping of the nozzle can be done with a finger, as well as with a hard object. </div>
<table style="border-collapse: collapse; width: 100%; border-style: none;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/e03a4297a772916ed43b160f9300a4b6_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/3226ee7326e5f8c4057eb46f4d9f8a55_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>Loadcell white pad - visual check </h3>
<div class="warning-callout">Ensure to have the <strong>PG-assembly-adapter</strong> before continuing with the following procedure. If you do not have it, you can print it using the below files, depending on the printer you will use: <br /><a href="https://files.printables.com/media/prints/451501/stls/4104840_55cb7d05-d1f6-4cca-8159-db9ac9f62942/pg-assembly-adapter-mk4-r1.stl">PG-assembly-adapter printed with MK4/S</a><br /><a href="https://files.printables.com/media/prints/451501/stls/4240522_6fa05937-693e-4282-8dce-a98d3e93fd5f/pg-assembly-adapter-mk3-r2.stl">PG-assembly-adapter printed with MK3/S/+</a></div>
<ol>
<li>If any filament is loaded, unload the filament, then wait for the printer to fully cool down. After that, turn the printer off.</li>
<li>Remove the PG-case, together with the PG-ring, gearbox, and main plate. Remove all of these parts in one piece. </li>
</ol>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/1c7df54642bb103d2a7d3ed01b41cbff_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/67c593556671a61a79c52036477d3454.jpg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<ol start="3">
<li>The top part of the loadcell is now visible and has a white pad attached to it. Without touching the white pad, check it for damage. </li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/4f0b8b4b2de761bec7c838efa8152ca9_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="500" height="375" loading="lazy" /></p>
<ol start="4">
<li>Reassemble the block of PG-case, PG-ring, gearbox, and main plate. In case the parts are not in one block, follow the dedicated steps from the Nextruder <a href="http://help.prusa3d.com/attachment/ltlznibfugnpwtwy-jpg_272">assembly manual</a>, depending on your printer version. </li>
<li>Perform the <a href="http://help.prusa3d.com/article/gearbox-alignment-core-one-mk4-s-mk3-9-s_465779">gearbox alignment</a>. </li>
</ol>
</div>


Loadcell Not Calibrated #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)

<h3>What happened?</h3>
<p>The <strong>Prusa CORE One</strong>, and the <strong>Original Prusa MK4/S</strong>, <strong>MK3.9/S</strong> are equipped with a <strong>loadcell</strong>, which detects whether the nozzle is close enough to the steel sheet for printing and prevents damage from the nozzle digging into the steel sheet. </p>
<p>In case the printer detects an incorrect loadcell configuration, but not related to the loadcell tare, or to the loadcell calibration, the printer will show the message: <strong>"The loadcell configuration is incorrect."</strong></p>
<p>Error name: Loadcell Bad Configuration</p>
<p>Error code: #31527 (CORE One) #26527 (MK4S) #13527 (MK4) #27527 (MK3.9S) #21527 (MK3.9)</p>
<h3>How to fix it? </h3>
<h4>A visual inspection</h4>
<div class="warning-callout">Before you start, make sure:</p>
<ul>
<li>the filament is unloaded from the extruder</li>
<li>the printer is turned OFF and unplugged from electricity</li>
<li>the hotend and the heatbed are cooled down to ambient temperature</li>
</ul>
</div>
<p>Access the right side of the LoveBoard, where the loadcell cable is connected. To remove the side LoveBoard cover, on CORE One loosen two<span style="color: #000000;"> <span style="color: #236fa1;"><strong>M3x6 bolts</strong></span></span>, on MK4/S and MK3.9/S loosen one <span style="color: #843fa1;"><strong>M3x10 bolt</strong></span>. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/c565b5d3a12f4e32b712cc273759d4e8_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Bad Configuration REVIEW #31527 (CORE One) #26527 (MK4S) #13527 (MK4) #27527 (MK3.9S) #21527 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/94e576c7396585eb388df6fd136a8ec8_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<p>Once accessed, locate the <span style="color: #e67e23;"><strong>loadcell connector</strong></span> and cable, and check for any loose cable, disconnected cable, or visible damage. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;">
<p style="text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/04/98f9151af765084ab2be69a52d63f20c_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></p>
</td>
<td style="width: 48.8562%; text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/3c492d1b5efc9c403a26bd3c455c2ea7_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h4><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/5e54e7bdd6fef88f48746c4095106a4f.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="500" height="375" loading="lazy" /></h4>
<h4>Re-test the loadcell</h4>
<div class="warning-callout">Do not manipulate or touch the printer unless the instructions on the printer screen prompt you to do so.</div>
<div>
<p>Navigate to <em>LCD Menu -&gt; Control -&gt; Calibrations &amp; Tests -&gt; Loadcell Test</em> to initiate a loadcell test. </p>
<p>During the test, you will be asked to tap the nozzle at a specific time, and a progress bar shown on the screen is filled, depending on the pressure applied to the loadcell. If the bar is not filled or is filled irregularly, please contact our <a href="http://help.prusa3d.com/article/customer-support_2287">customer support</a>. </p>
<div class="tip-callout">Tapping of the nozzle can be done with a finger, as well as with a hard object. </div>
<table style="border-collapse: collapse; width: 100%; border-style: none;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/e03a4297a772916ed43b160f9300a4b6_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/3226ee7326e5f8c4057eb46f4d9f8a55_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>Loadcell white pad - visual check </h3>
<div class="warning-callout">Ensure to have the <strong>PG-assembly-adapter</strong> before continuing with the following procedure. If you do not have it, you can print it using the below files, depending on the printer you will use: <br /><a href="https://files.printables.com/media/prints/451501/stls/4104840_55cb7d05-d1f6-4cca-8159-db9ac9f62942/pg-assembly-adapter-mk4-r1.stl">PG-assembly-adapter printed with MK4/S</a><br /><a href="https://files.printables.com/media/prints/451501/stls/4240522_6fa05937-693e-4282-8dce-a98d3e93fd5f/pg-assembly-adapter-mk3-r2.stl">PG-assembly-adapter printed with MK3/S/+</a></div>
<ol>
<li>If any filament is loaded, unload the filament, then wait for the printer to fully cool down. After that, turn the printer off.</li>
<li>Remove the PG-case, together with the PG-ring, gearbox, and main plate. Remove all of these parts in one piece. </li>
</ol>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/1c7df54642bb103d2a7d3ed01b41cbff_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/67c593556671a61a79c52036477d3454.jpg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<ol start="3">
<li>The top part of the loadcell is now visible and has a white pad attached to it. Without touching the white pad, check it for damage. </li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/4f0b8b4b2de761bec7c838efa8152ca9_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="500" height="375" loading="lazy" /></p>
<ol start="4">
<li>Reassemble the block of PG-case, PG-ring, gearbox, and main plate. In case the parts are not in one block, follow the dedicated steps from the Nextruder <a href="http://help.prusa3d.com/attachment/ltlznibfugnpwtwy-jpg_272">assembly manual</a>, depending on your printer version. </li>
<li>Perform the <a href="http://help.prusa3d.com/article/gearbox-alignment-core-one-mk4-s-mk3-9-s_465779">gearbox alignment</a>. </li>
</ol>
</div>


Loadcell Bad Configuration #31527 (CORE One) #26527 (MK4S) #13527 (MK4) #27527 (MK3.9S) #21527 (MK3.9)

<h3>What happened?</h3>
<p>The <strong>Prusa CORE One</strong>, and the <strong>Original Prusa MK4/S, MK3.9/S</strong> are equipped with a <strong>loadcell</strong>, to detect that the nozzle is close enough to the steel sheet for printing, and to avoid damage that would be caused by the nozzle digging into the steel sheet. </p>
<p>The loadcell sets itself a reference, called <strong>tare</strong>. In case there is an issue right before the start of this procedure, the printer will show the message: <strong>"There was an error requesting the tare for loadcell."</strong></p>
<p>Error name: Loadcell Tare Error</p>
<p>Error code: #31524 (CORE One) #26524 (MK4S) #13524 (MK4) #27524 (MK3.9S) #21524 (MK3.9)</p>
<h3>How to fix it? </h3>
<h4>A visual inspection</h4>
<div class="warning-callout">Before you start, make sure:</p>
<ul>
<li>the filament is unloaded from the extruder</li>
<li>the printer is turned OFF and unplugged from electricity</li>
<li>the hotend and the heatbed are cooled down to ambient temperature</li>
</ul>
</div>
<p>Access the right side of the LoveBoard, where the loadcell cable is connected. To remove the side LoveBoard cover, on CORE One loosen two<span style="color: #000000;"> <span style="color: #236fa1;"><strong>M3x6 bolts</strong></span></span>, on MK4/S and MK3.9/S loosen one <span style="color: #843fa1;"><strong>M3x10 bolt</strong></span>. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/c565b5d3a12f4e32b712cc273759d4e8_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Tare Error REVIEW #31524 (CORE One) #26524 (MK4S) #13524 (MK4) #27524 (MK3.9S) #21524 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/94e576c7396585eb388df6fd136a8ec8_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<p>Once accessed, locate the <span style="color: #e67e23;"><strong>loadcell connector</strong></span> and cable, and check for any loose cable, disconnected cable, or visible damage. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;">
<p style="text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/04/98f9151af765084ab2be69a52d63f20c_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></p>
</td>
<td style="width: 48.8562%; text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/3c492d1b5efc9c403a26bd3c455c2ea7_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h4><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/5e54e7bdd6fef88f48746c4095106a4f.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="500" height="375" loading="lazy" /></h4>
<h4>Re-test the loadcell</h4>
<div class="warning-callout">Do not manipulate or touch the printer unless the instructions on the printer screen prompt you to do so.</div>
<div>
<p>Navigate to <em>LCD Menu -&gt; Control -&gt; Calibrations &amp; Tests -&gt; Loadcell Test</em> to initiate a loadcell test. </p>
<p>During the test, you will be asked to tap the nozzle at a specific time, and a progress bar shown on the screen is filled, depending on the pressure applied to the loadcell. If the bar is not filled or is filled irregularly, please contact our <a href="http://help.prusa3d.com/article/customer-support_2287">customer support</a>. </p>
<div class="tip-callout">Tapping of the nozzle can be done with a finger, as well as with a hard object. </div>
<table style="border-collapse: collapse; width: 100%; border-style: none;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/e03a4297a772916ed43b160f9300a4b6_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/3226ee7326e5f8c4057eb46f4d9f8a55_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>Loadcell white pad - visual check </h3>
<div class="warning-callout">Ensure to have the <strong>PG-assembly-adapter</strong> before continuing with the following procedure. If you do not have it, you can print it using the below files, depending on the printer you will use: <br /><a href="https://files.printables.com/media/prints/451501/stls/4104840_55cb7d05-d1f6-4cca-8159-db9ac9f62942/pg-assembly-adapter-mk4-r1.stl">PG-assembly-adapter printed with MK4/S</a><br /><a href="https://files.printables.com/media/prints/451501/stls/4240522_6fa05937-693e-4282-8dce-a98d3e93fd5f/pg-assembly-adapter-mk3-r2.stl">PG-assembly-adapter printed with MK3/S/+</a></div>
<ol>
<li>If any filament is loaded, unload the filament, then wait for the printer to fully cool down. After that, turn the printer off.</li>
<li>Remove the PG-case, together with the PG-ring, gearbox, and main plate. Remove all of these parts in one piece. </li>
</ol>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/1c7df54642bb103d2a7d3ed01b41cbff_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/67c593556671a61a79c52036477d3454.jpg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<ol start="3">
<li>The top part of the loadcell is now visible and has a white pad attached to it. Without touching the white pad, check it for damage. </li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/4f0b8b4b2de761bec7c838efa8152ca9_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="500" height="375" loading="lazy" /></p>
<ol start="4">
<li>Reassemble the block of PG-case, PG-ring, gearbox, and main plate. In case the parts are not in one block, follow the dedicated steps from the Nextruder <a href="http://help.prusa3d.com/attachment/ltlznibfugnpwtwy-jpg_272">assembly manual</a>, depending on your printer version. </li>
<li>Perform the <a href="http://help.prusa3d.com/article/gearbox-alignment-core-one-mk4-s-mk3-9-s_465779">gearbox alignment</a>. </li>
</ol>
</div>


Loadcell Tare Error #31524 (CORE One) #26524 (MK4S) #13524 (MK4) #27524 (MK3.9S) #21524 (MK3.9)

<h3>What happened?</h3>
<p>The <strong>Prusa CORE One</strong>, and the <strong>Original Prusa MK4/S</strong>, <strong>MK3.9/S</strong> are equipped with a <strong>loadcell</strong>, which detects whether the nozzle is close enough to the steel sheet for printing and prevents damage from the nozzle digging into the steel sheet. </p>
<p>The loadcell sets itself a reference, called <strong>tare</strong>. In case there is an issue during this procedure, the printer will show the message: <strong>"Setting the tare failed. Check the loadcell wiring and connection."</strong></p>
<p>Error name: Loadcell Tare Failed </p>
<p>Error code: #31525 (CORE One) #26525 (MK4S) #13525 (MK4) #27525 (MK3.9S) #21525 (MK3.9)</p>
<h3>How to fix it? </h3>
<h4>A visual inspection</h4>
<div class="warning-callout">Before you start, make sure:</p>
<ul>
<li>the filament is unloaded from the extruder</li>
<li>the printer is turned OFF and unplugged from electricity</li>
<li>the hotend and the heatbed are cooled down to ambient temperature</li>
</ul>
</div>
<p>Access the right side of the LoveBoard, where the loadcell cable is connected. To remove the side LoveBoard cover, on CORE One loosen two<span style="color: #000000;"> <span style="color: #236fa1;"><strong>M3x6 bolts</strong></span></span>, on MK4/S and MK3.9/S loosen one <span style="color: #843fa1;"><strong>M3x10 bolt</strong></span>. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/c565b5d3a12f4e32b712cc273759d4e8_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Tare Failed REVIEW #31525 (CORE One) #26525 (MK4S) #13525 (MK4) #27525 (MK3.9S) #21525 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/94e576c7396585eb388df6fd136a8ec8_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<p>Once accessed, locate the <span style="color: #e67e23;"><strong>loadcell connector</strong></span> and cable, and check for any loose cable, disconnected cable, or visible damage. </p>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;">
<p style="text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/04/98f9151af765084ab2be69a52d63f20c_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></p>
</td>
<td style="width: 48.8562%; text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/3c492d1b5efc9c403a26bd3c455c2ea7_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h4><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/5e54e7bdd6fef88f48746c4095106a4f.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell Not Calibrated REVIEW #31523 (CORE One) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)" alt="" width="500" height="375" loading="lazy" /></h4>
<h4>Re-test the loadcell</h4>
<div class="warning-callout">Do not manipulate or touch the printer unless the instructions on the printer screen prompt you to do so.</div>
<div>
<p>Navigate to <em>LCD Menu -&gt; Control -&gt; Calibrations &amp; Tests -&gt; Loadcell Test</em> to initiate a loadcell test. </p>
<p>During the test, you will be asked to tap the nozzle at a specific time, and a progress bar shown on the screen is filled, depending on the pressure applied to the loadcell. If the bar is not filled or is filled irregularly, please contact our <a href="http://help.prusa3d.com/article/customer-support_2287">customer support</a>. </p>
<div class="tip-callout">Tapping of the nozzle can be done with a finger, as well as with a hard object. </div>
<table style="border-collapse: collapse; width: 100%; border-style: none;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/e03a4297a772916ed43b160f9300a4b6_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/3226ee7326e5f8c4057eb46f4d9f8a55_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>Loadcell white pad - visual check </h3>
<div class="warning-callout">Ensure to have the <strong>PG-assembly-adapter</strong> before continuing with the following procedure. If you do not have it, you can print it using the below files, depending on the printer you will use: <br /><a href="https://files.printables.com/media/prints/451501/stls/4104840_55cb7d05-d1f6-4cca-8159-db9ac9f62942/pg-assembly-adapter-mk4-r1.stl">PG-assembly-adapter printed with MK4/S</a><br /><a href="https://files.printables.com/media/prints/451501/stls/4240522_6fa05937-693e-4282-8dce-a98d3e93fd5f/pg-assembly-adapter-mk3-r2.stl">PG-assembly-adapter printed with MK3/S/+</a></div>
<ol>
<li>If any filament is loaded, unload the filament, then wait for the printer to fully cool down. After that, turn the printer off.</li>
<li>Remove the PG-case, together with the PG-ring, gearbox, and main plate. Remove all of these parts in one piece. </li>
</ol>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/1c7df54642bb103d2a7d3ed01b41cbff_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/67c593556671a61a79c52036477d3454.jpg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<ol start="3">
<li>The top part of the loadcell is now visible and has a white pad attached to it. Without touching the white pad, check it for damage. </li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/11/4f0b8b4b2de761bec7c838efa8152ca9_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Loadcell troubleshooting" alt="" width="500" height="375" loading="lazy" /></p>
<ol start="4">
<li>Reassemble the block of PG-case, PG-ring, gearbox, and main plate. In case the parts are not in one block, follow the dedicated steps from the Nextruder <a href="http://help.prusa3d.com/attachment/ltlznibfugnpwtwy-jpg_272">assembly manual</a>, depending on your printer version. </li>
<li>Perform the <a href="http://help.prusa3d.com/article/gearbox-alignment-core-one-mk4-s-mk3-9-s_465779">gearbox alignment</a>. </li>
</ol>
</div>


Loadcell Tare Failed #31525 (CORE One) #26525 (MK4S) #13525 (MK4) #27525 (MK3.9S) #21525 (MK3.9)

<h3>What happened?</h3>
<p>The <strong>Prusa CORE One</strong>, and the <strong>Original Prusa MK4/S</strong>, <strong>MK3.9/S</strong>, and <strong>MK3.5/S</strong> electronic boards have memory: the printer manages its allocation autonomously. In case of an issue in memory management that affects an LED animation, the printer will show the message <strong>"Memory allocation failed for scheduled LED animation"</strong></p>
<p>Error name: LED Memory Error</p>
<p>Error code: #31529 (CORE One) #26529 (MK4S) #13529 (MK4) #27529 (MK3.9S) #21529 (MK3.9) #28529 (MK3.5S) #23529 (MK3.5)</p>
<h3>How to fix it? </h3>
<p><strong>Restarting the printer</strong> is expected to resolve the error, and this is not expected to occur again. In case a restart does not resolve it, please contact our <a href="http://help.prusa3d.com/article/customer-support_2287">customer support</a>, and we will take it from here. </p>


LED Memory Error #31529 (CORE One) #26529 (MK4S) #13529 (MK4) #27529 (MK3.9S) #21529 (MK3.9) #28529 (MK3.5S) #23529 (MK3.5)

<p>You can recognize under extrusion when there is material missing in your print’s layers. Printed objects with under extruded layers can be fragile and tend to break apart. There could be several causes to under-extrusion and you should also think if you recently did any changes to your printer (or perhaps no maintenance for a long period), as you might find the culprit there.</p>
<p style="text-align: center;"><em><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/underextrusion.jpg" alt="" width="600" height="261" loading="lazy" />Example of severe under extrusion (left cube) and a normal print (right cube).</em></p>
<p><strong>Common factors in under extru</strong><strong>sions on printers equipped with Nextruder are:</strong></p>
<ul>
<li>Nozzle</li>
<li>Slicer settings</li>
<li>Gearbox</li>
<li>Filament</li>
</ul>
<h3>Nozzle</h3>
<div class="warning-callout">Before proceeding further, make sure that the printer is <strong>FULLY COOLED DOWN AT ROOM TEMPERATURE</strong>, and <strong>switched OFF</strong>! </div>
<p>The nozzle on the Nextruder has to be at the correct height and tightened.</p>
<h4>CORE One, MK4/S, MK3.9/S</h4>
<p>To check this aspect, loosen the <span style="color: #169179;"><strong>thumb screws</strong></span> (do not completely remove the screws, a few turns are enough) on the side of the heatbreak, and <span style="color: #000000;"><strong>push the nozzle up</strong></span>. <span style="color: #e67e23;"><strong>The copper ring on the tube should not be visible</strong></span>.</p>
<p>Tighten the thumb screws just <strong>by hand</strong>, <strong>do not use any tools</strong>. </p>
<p>If you have a <a href="http://help.prusa3d.com/guide/how-to-install-the-nextruder-v6-nozzle-adapter-mk4-mk3-9_416174">Nozzle Adapter</a>, check the installation again to make sure that the nozzle has not been lowered or loosened with the installation of the adapter. </p>
<table style="border-collapse: collapse; width: 100%; height: 320.493px;" border="1">
<tbody>
<tr style="height: 299.604px;">
<td style="width: 50.0545%; height: 299.604px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/ac5a00b1850be25cab122f7dd5a3f15d_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Under-extrusion REVIEW (Nextruder printers)" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 49.9318%; height: 299.604px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/2b1c0fd708cd92b019e69db36327ff2c_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Under-extrusion REVIEW (Nextruder printers)" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
<tr style="height: 20.8889px;">
<td style="height: 20.8889px; text-align: center; width: 99.9864%;" colspan="2"><em>Prusa CORE One</em></td>
</tr>
</tbody>
</table>
<div> </div>
<table border="1">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/42ad5a5d42d57434d6b94348c2371df2_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Under-extrusion REVIEW (Nextruder printers)" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2025/01/cecb7b9c53bd7e9645854eb08d33ac1b_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Under-extrusion REVIEW (Nextruder printers)" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
<tr>
<td style="width: 48.8562%; text-align: center;"><em>MK4S, MK3.9S</em></td>
<td style="width: 48.8562%; text-align: center;"><em>MK4, MK3.9</em></td>
</tr>
</tbody>
</table>
<h4>XL</h4>
<p>For the following procedure, where the hotend is temporarily extracted and reassembled, you can refer to the hotend replacement guide. </p>
<ul>
<li><a href="http://help.prusa3d.com/guide/how-to-replace-the-hotend-assembly-xl-single-tool_409911">XL single-tool</a></li>
<li><a href="http://help.prusa3d.com/guide/how-to-replace-the-hotend-assembly-xl-multi-tool_573711">XL multi-tool</a></li>
</ul>
<p>Temporarily extract the nozzle and check whether the metal nozzle tube has a <strong>dent</strong>. If it has, the nozzle needs to be replaced. </p>
<div class="note-callout">The cause of a dented Nozzle tube is overtightening of the grub screw, hence this is not covered by our <a href="http://help.prusa3d.com/article/warranty_2288">warranty</a>, unless it arrived like this from our factory. </div>
<div>After this check, if the nozzle tube was in good visible status, reassemble the hotend. This will ensure the correct positioning of the nozzle. </div>
<p>On single-tool XL, <strong><span style="color: #ba372a;">use the Torx TX8 key</span></strong> as shown in the picture to adjust the set screw. Do not use extra force while tightening, it may damage the hotend tube. The nozzle must be approximately at a <span style="color: #e67e23;"><strong>35°-40° angle</strong></span> to avoid damaging the hotend cables.</p>
<table style="border-collapse: collapse; width: 100%;">
<tbody>
<tr>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/03/eddd406fd9a07bf6_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
<td style="width: 48.8562%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/03/2f1281fee89b9362_painted.jpeg" alt="" width="395" height="296" loading="lazy" /></td>
</tr>
</tbody>
</table>
<p>On multi-tool XL, use the Torx TX8 key <span style="color: #169179;"><strong>in the part shown in the picture</strong></span> to adjust the set screw. Do not use extra force while tightening, it may damage the hotend tube. The nozzle must be approximately at a 35°-40° angle to avoid damaging the hotend cables.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/10/3ce1d1b154d7efa2ddbba4894efc1ad4_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Nozzle Cleaning Failed (XL)" alt="" width="600" height="450" loading="lazy" /></p>
<h3>Slicer settings</h3>
<p>Each profile in the PrusaSlicer contains settings that determine temperature, speeds, and how much filament the 3D printer should extrude. The printer does not provide any feedback on how much filament actually leaves the nozzle. It can be that less filament is extruded than the firmware expects. If that happens, you may notice gaps in and/or in between printed layers.</p>
<p>Make sure you have set up your printer in PrusaSlicer by running the <a href="http://help.prusa3d.com/article/configuration-wizard_1754">Configuration Wizard</a> and as a starting point you should use the stock filament profiles which are tailored for your machine, filament type, and nozzle size. </p>
<h3>Gearbox alignment</h3>
<p>It is possible, especially after interventions that involve the opening of the gearbox cover, that the gearbox is not fully aligned, causing an under-extrusion issue. Below are the procedures to align the gearbox. </p>
<h4>CORE One, MK4/S, MK3.9/S</h4>
<p>Follow the dedicated <a href="http://help.prusa3d.com/article/gearbox-alignment-core-one-mk4-s-mk3-9-s_465779">gearbox alignment</a> article for these printer models. </p>
<h4>XL </h4>
<p>The Original Prusa XL does not have an automatic gearbox alignment procedure. Perform these steps to reproduce the same movement. If loaded, unload the filament from the printer before proceeding. </p>
<ol>
<li>Slightly <span style="color: #169179;"><strong>loosen the three bolts on the gearbox cover</strong></span>, by one turn and a half. </li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/02/dcc35141d93045f25c43003a5ef109a0_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Under-extrusion (Nextruder printers)" alt="" width="400" height="300" loading="lazy" /></p>
<ol start="2">
<li>On the LCD Menu, navigate to <em>Filament -&gt; Unload Filament</em>.</li>
<li>As soon as the extruder's movement finishes, <span style="color: #169179;"><strong>tighten the three M3x25 screws</strong></span> on the gearbox cover, in the order specified in the picture. </li>
</ol>
<h3>Filament</h3>
<p>A printing temperature that is too low or too high can cause print issues as well. If your filament brand and type are not listed in PrusaSlicer, you can try to adjust the print temperature by +/- 5-15°C to see if this resolves the issue.</p>
<p>Some specialty materials, like <a href="http://help.prusa3d.com/article/flexible-materials_2057">Flexible materials</a>, may require many adjustments and tweaks to print them successfully. <a href="http://help.prusa3d.com/article/composite-materials-filled-with-carbon-kevlar-or-glass_167387">Composite materials</a>, like Woodfill filament, may require at minimum a 0.6 mm nozzle, and 0.2 mm layer height to prevent clogging. If there are composite materials like kevlar or carbon fiber, a <a href="http://help.prusa3d.com/article/different-nozzle-types_2193#hardened-steel-nozzle-by-e3d">hardened nozzle is required</a>.</p>
<div class="tip-callout">Be sure to see <a href="https://help.prusa3d.com/en/materials">our extensive material table</a>, where most types of filament and their considerations are covered.</div>
<p>Some filaments can also have varying thickness, due to quality or infused materials like wood, which will cause unexpected changes in the volume of extruded filament. The industry standard for variations in diameter is +/- 0.05 mm.</p>
<p>Keep your filament dry, and free of moisture because damp filaments have a negative impact on printing, especially soluble filament, PETG, and ABS. We highly recommend putting spools back inside their original bag when it’s not in use, along with a silica gel. We recommend storing your filaments in a dry area or ideally in a “dry box”.</p>
<h4>Incorrect loading/unloading</h4>
<p>When loading a new filament with a lower specified temperature, preheat the nozzle to the temperature required by the previous filament type you have used. In other words, always to the highest temperature filament, as its remnants are most likely still in the hotend. For example, <strong>if you have printed with ABS or PETG and want to print with PLA now, load the PLA filament at the ABS or PETG temperature.</strong> This way, the newly introduced filament can push the old one out.</p>
<h4>Low-temperature materials and enclosure</h4>
<p>Printing PLA or a similar material in an enclosed printer can cause under-extrusion. </p>
<p>For example, on our Original Prusa Enclosure with closed doors, if the ambient temperature is over 27°C, the temperature inside the enclosure may be too high for printing PLA or similar materials, causing under-extrusion or clogging. </p>


Under-extrusion (Nextruder printers)

<h3>What happened?</h3>
<p>If your printer shows the message "Firmware and hardware versions do not match. Make sure you have the right firmware file for your printer," you might have installed an incorrect firmware version.</p>
<p><strong>Error name:</strong> Firmware x printer mismatch</p>
<p><strong>Error code:</strong> #12609 (MINI/+) #13609 (MK4) #17609 (XL) #21609 (MK3.9) #23609 (MK3.5) #26609 (MK4S) #27609 (MK3.9S) #28609 (MK3.5S) #31609 (CORE One)</p>
<h3>How to fix it?</h3>
<p>Go to the Prusa <a href="https://www.prusa3d.com/drivers/">downloads</a> page or <a href="https://github.com/prusa3d">Github</a>, and download the correct firmware for your printer. If you are unsure what your printer version is, contact our <a href="http://help.prusa3d.com/article/customer-support_2287">Customer support</a> with your <a href="http://help.prusa3d.com/article/original-prusa-serial-number_134171">Original Prusa Serial Number</a> and pictures of your printer so we can help you identify it.</p>
<p>Flashing the firmware by doing a <a href="http://help.prusa3d.com/article/factory-reset-core-one-mk4-s-mk3-9-s-mk3-5-s-mini-xl_421206">hard factory reset</a> is also possible.</p>
<p> </p>


Firmware x printer mismatch #12609 (MINI/+) #13609 (MK4) #17609 (XL) #21609 (MK3.9) #23609 (MK3.5) #26609 (MK4S) #27609 (MK3.9S) #28609 (MK3.5S) #31609 (CORE One)

<h3>What happened?</h3>
<p>Steel sheet was not detected. Please put the sheet on to prevent printer damage.</p>
<p>Error name: Steel sheet not detected</p>
<p>Error code: #31109</p>
<h3>How to fix it?</h3>
<p>Place the <a href="http://help.prusa3d.com/article/flexible-steel-sheets-guidepost_2195">print sheet</a> on the heatbed. If the issue persists after placing the sheet, check the <a href="http://help.prusa3d.com/article/loadcell-troubleshooting_815397">Loadcell</a>. Check also if the nozzle is not on the very edge of the sheet.</p>
<p>If the issue happens when using a third-party steel sheet, try using a slightly thicker sheet.</p>
<p> </p>


Steel sheet not detected #31109


<ul>
<li>Multiple beds and bulk export</li>



<li>Scarf seams</li>



<li>Printables integration</li>



<li>Paint-on fuzzy skin</li>



<li>Improvements in painting tools and multi-material slicing</li>



<li>Basic support for printing with different nozzle diameters</li>
</ul>


Prusa CORE One