MK3S+

Shipping information

<div>
<h3 dir="ltr">Stable releases</h3>
<p dir="ltr">The latest <strong>stable release</strong> of PrusaSlicer can be always found in the <a href="https://www.prusa3d.com/drivers/">DRIVERS &amp; APPS package</a> and it’s available for Windows, Mac OS X, and Linux. The package also includes test objects and printer drivers, but you can choose to install only PrusaSlicer.</p>
<p dir="ltr">You can also download a standalone installer for your computer at <a href="https://www.prusa3d.com/page/prusaslicer_424/">PrusaSlicer introduction &amp; download</a> or at <a href="https://github.com/prusa3d/PrusaSlicer/releases">our GitHub</a>.</p>
<p dir="ltr">Stable releases are versions that have been tested as thoroughly as possible and have gone through numerous public alpha- and beta-versions.</p>
<h3 dir="ltr">Alpha and Beta releases</h3>
<p dir="ltr">Do you want to keep up with PrusaSlicer’s fast development pace? Development builds have the latest features and bug fixes. However, they can be unstable, crash, or behave unexpectedly. We do not recommend using development builds in production environments. Check out <a href="https://github.com/prusa3d/PrusaSlicer/releases">our GitHub</a> for downloads and more info.</p>
<div class="tip-callout">For how to install PrusaSlicer on most computers, see our article <a href="http://help.prusa3d.com/article/install-prusaslicer_1903">Install PrusaSlicer</a>.</div>
</div>


Download PrusaSlicer

<p dir="ltr">3D printers work by laying layer over layer of plastic to create a 3D object. Each new layer must be supported by the one beneath it. If part of your model starts in mid-air and is not supported by anything below, you need to add an additional support structure to ensure a successful print.</p>
<div class="tip-callout">It is worth considering altering the orientation of the model or splitting the model into multiple parts in order to possibly reduce overhangs and consequently the amount of supports generated.</div>
<p dir="ltr">PrusaSlicer can both detect areas that need supports and generate them in these places <strong>automatically</strong>.</p>
<p dir="ltr">You can also set supports manually using:</p>
<ul>
<li dir="ltr"><a href="http://help.prusa3d.com/article/paint-on-supports_168584">Paint on supports</a></li>
<li dir="ltr"><a href="http://help.prusa3d.com/article/modifier-meshes-custom-supports-and-other-magic_114258#custom-supports">Support enforcers and blockers</a></li>
</ul>
<p dir="ltr">Supports can be turned on from the <strong>right panel</strong> or in the <strong>Print settings - Support material - Generate support material</strong>.</p>
<p dir="ltr">There are 3 different Support styles in PrusaSlicer</p>
<ul>
<li dir="ltr">Grid</li>
<li dir="ltr">Snug</li>
<li dir="ltr"><a href="http://help.prusa3d.com/article/organic-supports_480131">Organic</a></li>
</ul>
<p dir="ltr">When the print finishes, depending on the model geometry and material used, the support structure is often easily removable with bare hands. You can use pliers to get a better grip in otherwise hard-to-reach places. A scalpel or a utility knife can also be used to cleanly remove a piece of support that seems to be stuck to the model.</p>
<div class="warning-callout">Pieces of supports can be surprisingly sharp and are sometimes violently ejected in a random direction after removal. When you encounter hard-to-remove supports, <strong>consider wearing protective glasses</strong> (this sounds stupid until you get hit in the eye for the first time).</div>
<h3 dir="ltr">Supports everywhere</h3>
<p dir="ltr">Supports can grow from both the print bed and any model surface when necessary. </p>
<p dir="ltr">This ensures that every overhang and part starting mid-air will get supported. However, small imperfections may appear on the surface where supports started growing from.</p>
<h3 dir="ltr">Supports from build plate only</h3>
<p>Creates only supports that have their base at the print bed.</p>
<p><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/everywhere_build_plate_only.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/everywhere_build_plate_only-300x171.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/everywhere_build_plate_only-600x343.jpg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/everywhere_build_plate_only-768x439.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/everywhere_build_plate_only-800x457.jpg 800w" alt="" /></p>
<p style="text-align: center;"><em>Supports from build plate only (left), supports everywhere (right)</em></p>
<h3 dir="ltr">For support enforcers only</h3>
<p dir="ltr">Automatic support generation is enabled only for areas marked with a support enforcer. This option is essentially a shortcut that turns <strong>Print settings - Support material - Generate support material</strong> on, but <strong>Print settings - Support material - Auto-generated supports</strong> off.</p>
<h3 dir="ltr">Supports on/off for individual models</h3>
<p dir="ltr">It’s possible to print multiple objects at once each with its own support settings. By default, all models are affected by the global settings. You can overwrite them by <strong>right-clicking</strong> on a model in the 3D view and selecting <strong>Support material</strong>. Alternatively, you can right-click on the editing icon in the Object list.</p>
<p dir="ltr">A new window will appear in the right panel called <strong>Object settings to modify - Support material</strong>. Changing these settings will affect only the relevant object and its instances. You can remove the settings overwrite by clicking on the red cross icon. When you do so, the global settings will once again be applied.</p>
<p dir="ltr"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/supports_per_object-2.png" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/supports_per_object-2-300x149.png 300w, https://cdn.help.prusa3d.com/wp-content/uploads/supports_per_object-2-600x299.png 600w, https://cdn.help.prusa3d.com/wp-content/uploads/supports_per_object-2-768x383.png 768w, https://cdn.help.prusa3d.com/wp-content/uploads/supports_per_object-2-800x399.png 800w" alt="" width="495" height="247" loading="lazy" /></p>
<h3 dir="ltr">Support enforcer/blocker</h3>
<p dir="ltr">The automatic supports can sometimes appear in hard-to-reach places, resulting in a tedious removal of support structures. If you think such a part of the model could be printed without supports, but neither the <strong>Overhang threshold</strong> setting nor selecting <strong>Supports on built plate only</strong> helped, you can adjust supports manually.</p>
<div class="tip-callout">Starting with PrusaSlicer 2.3, you can also use <a href="http://help.prusa3d.com/article/paint-on-supports_168584">Paint on supports</a>.</div>
<p dir="ltr"><strong>Right-click</strong> on a model and choose either a <strong>Support blocker or Support enforcer</strong>.</p>
<p dir="ltr"><span style="color: #2dc26b;"><strong>Simple mode</strong></span> - Enforcers/blockers are always box-shaped</p>
<p dir="ltr"><span style="color: #f1c40f;"><strong>Advanced mode</strong></span> - Box/Cylinder/Sphere/Slab shapes</p>
<p dir="ltr"><span style="color: #ba372a;"><strong>Expert mode</strong></span> - Option to load external geometry as a blocker/enforcer</p>
<p dir="ltr">Support blockers and enforcers can be manipulated with the familiar Move, Rotate, and Scale tools. You can also quickly duplicate them with copy&amp;paste.</p>
<h3 dir="ltr">Support blocker</h3>
<p dir="ltr">Support blockers are useful when you’re generally happy with the automatic supports and you simply want to remove some of them. Focus on placing blockers where the supports meet the object, the rest of the support structure below will be removed automatically.</p>
<h3 dir="ltr">Support enforcers</h3>
<p dir="ltr">Support enforcers are great in situations, where only a few parts of the object need to be supported, but the automatic algorithm places supports all over the model. In this situation, don’t forget to switch the support mode to For support enforcers only. </p>
<p dir="ltr">It’s less common, but you can also use support enforcers with the automatic generation on.</p>
<p dir="ltr">Another interesting use of support enforcers is to split long bridges into smaller ones by placing a support in the middle of the bridge. You can repeat this process and print shorter, near-perfect bridges while still making the supports easy to remove.</p>
<div class="note-callout">Some options will only appear when <a href="http://help.prusa3d.com/article/simple-advanced-expert-modes_1765">Expert mode</a> is selected.</div>
<h3 dir="ltr"><strong>Generate support material</strong></h3>
<p dir="ltr">Supports are disabled unless a model has an overwrite for this setting</p>
<h3 dir="ltr"><strong>Auto-generated supports</strong></h3>
<p dir="ltr">When off, the overhang detection is off. Only support enforcers generate supports.</p>
<h3 dir="ltr"><strong>Overhang threshold</strong></h3>
<p dir="ltr">The Overhang threshold value represents the most horizontal slope (measured from the horizontal plane) that you can print without support material (90=vertical).</p>
<p dir="ltr">Changing this value is a quick way to adjust the amount of generated supports.</p>
<p dir="ltr">The lower the value, the less support will be generated.</p>
<p dir="ltr"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/support_overhang_threshold.png" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/support_overhang_threshold-300x171.png 300w, https://cdn.help.prusa3d.com/wp-content/uploads/support_overhang_threshold-600x342.png 600w, https://cdn.help.prusa3d.com/wp-content/uploads/support_overhang_threshold-768x437.png 768w, https://cdn.help.prusa3d.com/wp-content/uploads/support_overhang_threshold-800x455.png 800w" alt="" /></p>
<ol>
<li dir="ltr" role="presentation">The Overhang threshold value and how it's measured</li>
<li dir="ltr" role="presentation">Overhang threshold 55</li>
<li dir="ltr" role="presentation">Overhang threshold 35</li>
<li dir="ltr" role="presentation">Overhang threshold 15</li>
</ol>
<h3 dir="ltr"><strong>Enforce support for the first</strong></h3>
<p dir="ltr">Generate support material for the specified number of layers counting from the bottom, regardless of whether normal support material is enabled or not and regardless of any angle threshold. This is useful for getting more adhesion of objects having a very thin or poor footprint on the build plate.</p>
<p dir="ltr" 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/enforce_for_layers.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/enforce_for_layers-300x204.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/enforce_for_layers-587x400.jpg 587w, https://cdn.help.prusa3d.com/wp-content/uploads/enforce_for_layers-768x523.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/enforce_for_layers-800x545.jpg 800w" alt="" /><em>Enforce support for the first 100 layers</em></p>
<h3 dir="ltr"><strong>Raft layers</strong></h3>
<p dir="ltr">The object will be raised by this number of layers and support material will be generated under it. When the print finishes, you can grab the raft and peel it away from the part.</p>
<h3 dir="ltr">Raft contact Z distance</h3>
<p>The vertical distance between the raft and the object. Ignored for soluble interfaces.</p>
<h3>Raft expansion</h3>
<p>Expansion of the raft in the XY plane for better stability.</p>
<h3>Style</h3>
<p>Style and shape of supports. The default <strong>Grid</strong> supports have a very well-defined minimum area, making them very stable. However, they tend to leak out of regions they support along the walls of the object. The <strong>Snug</strong> supports maintain the shape of the overhang, so they do not leak to the walls. The trade-off is the possibility of lower stability of tall and thin support pillars.</p>
<p><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2022/01/snug_vs_grid.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2022/01/snug_vs_grid-600x190.jpg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/2022/01/snug_vs_grid-800x253.jpg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/2022/01/snug_vs_grid-300x95.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2022/01/snug_vs_grid-768x243.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/2022/01/snug_vs_grid-1536x485.jpg 1536w, https://cdn.help.prusa3d.com/wp-content/uploads/2022/01/snug_vs_grid-2048x647.jpg 2048w, https://cdn.help.prusa3d.com/wp-content/uploads/2022/01/snug_vs_grid.jpg 1600w" alt="" width="1847" height="584" loading="lazy" /></p>
<p style="text-align: center;"><em>Grid supports (left), Snug supports (right)</em></p>
<p><a href="https://help.prusa3d.com/article/organic-supports_480131"><strong>Organic supports</strong></a> offer a completely different approach to supporting overhanging areas. Branches of support structures grow from the sides and automatically get denser beneath parts that need the support. The Organic supports are easily removable, do not scar the surface, and are fast and cheap to print.</p>
<figure class="image" style="text-align: center;"><img decoding="async" title="Support material" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/07/30cd916294dd7ac737ac7c09e1edfbb9.jpg" alt="" width="2011" height="1119" loading="lazy" /><figcaption>Grid supports (left), Organic supports (right)</figcaption></figure>
<h3 dir="ltr"><strong>Top contact Z distance</strong></h3>
<p dir="ltr">The vertical distance between the object and the support material interface.</p>
<p dir="ltr">Setting this to 0 will prevent PrusaSlicer from using bridge flow and speed for the first object layer.</p>
<p dir="ltr">Values between 50-75% of the layer height seem to work well.</p>
<p dir="ltr"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/contact_z_distance.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/contact_z_distance-300x191.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/contact_z_distance-600x381.jpg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/contact_z_distance-768x488.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/contact_z_distance-800x508.jpg 800w" alt="" /></p>
<h3 dir="ltr">Bottom contact Z distance</h3>
<p>Similar to Top contact Z distance, but affecting the gap at the bottom of the support tower (when supports start on top of a model and not on the build plate).</p>
<h3 dir="ltr"><strong>Pattern</strong></h3>
<p dir="ltr">Rectilinear - default, usually the easiest to remove</p>
<p dir="ltr">Rectilinear grid - sturdier and less prone to breaking during printing compared to rectilinear infill, harder to remove</p>
<p dir="ltr">Honeycomb - sturdy, somewhat difficult to remove</p>
<h3 dir="ltr"><strong>With sheath around the support</strong></h3>
<p dir="ltr">Creates a single perimeter around the supports, which makes them sturdier, but more difficult to remove.</p>
<h3 dir="ltr"><strong>Pattern spacing</strong></h3>
<p dir="ltr">Spacing between support material lines. Increase to make support removal easier. Support interface layers bridge over support material lines, if you increase this value too much, these bridges will start to sag and have an imperfect connection with the model.</p>
<p dir="ltr">The pattern spacing also sets the internal resolution of PrusaSlicer's supports grid. If you're using Paint-on supports or Support enforcers and you're unable to force supports exactly where you want them to be, try lowering the pattern spacing to get more resolution.</p>
<h3 dir="ltr"><strong>Pattern angle</strong></h3>
<p dir="ltr">Rotates infill pattern angle on the horizontal plane.</p>
<h3 dir="ltr">Closing radius</h3>
<p>For Snug supports only. Gaps smaller than the closing radius will be filled in.</p>
<h3 dir="ltr"><strong>Top interface layers</strong></h3>
<p dir="ltr">Interface layers form a more uniform surface between the object and the support material. These are preferably set to a much denser pattern than the non-interface layers so that you can both maximize the surface area of the support in contact with the model to prevent sagging while minimizing print time and material used with a bigger non-interface pattern spacing.</p>
<h3 dir="ltr">Bottom interface layers</h3>
<p>Similar as Top interface layers, but affecting the number of interface layers at the bottom of the support tower (when supports start on top of a model and not on the build plate).</p>
<h3 dir="ltr"><strong>Interface pattern spacing</strong></h3>
<p dir="ltr">Spacing between interface lines. Set to 0 to get a solid interface.</p>
<h3 dir="ltr"><strong>Interface loops</strong></h3>
<p dir="ltr">When enabled, the top layer of supports is covered with loops - continuous polylines.</p>
<h3 dir="ltr"><strong>Support on build plate only</strong></h3>
<p dir="ltr">Supports can start only on the print bed. Enabling this option is a really quick way to get rid of excess supports mostly on organic shapes. Make sure to check the preview and verify that all parts are either supported or at an overhang angle manageable by the printer.</p>
<p dir="ltr"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/supports_build_plate_only.png" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/supports_build_plate_only-300x178.png 300w, https://cdn.help.prusa3d.com/wp-content/uploads/supports_build_plate_only-600x356.png 600w, https://cdn.help.prusa3d.com/wp-content/uploads/supports_build_plate_only-768x455.png 768w, https://cdn.help.prusa3d.com/wp-content/uploads/supports_build_plate_only-800x474.png 800w" alt="" /></p>
<p dir="ltr" style="text-align: center;"><em>Supports everywhere (left) vs Supports on build plate only (right)</em></p>
<h3 dir="ltr"><strong>XY separation between an object and its support</strong></h3>
<p dir="ltr">Sets the width of a gap between the model and supports. Bigger XY separation decreases the contact area of supports but makes them easier to remove and less prone to fusing to the model.</p>
<p dir="ltr">If expressed as a percentage (for example 150%) it will be calculated over the external perimeter width.</p>
<p dir="ltr"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/XY_seperation-1.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/XY_seperation-1-300x151.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/XY_seperation-1-600x301.jpg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/XY_seperation-1-768x386.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/XY_seperation-1-800x402.jpg 800w" alt="" /></p>
<h3 dir="ltr"><strong>Don’t support bridges</strong></h3>
<p dir="ltr">Prevents support material from being generated under bridged areas.</p>
<h3 dir="ltr"><strong>Synchronize with object layers</strong></h3>
<p dir="ltr">Supports will be printed at equal layer heights as the model itself. This is useful with multi-material printers, where the extruder switch is expensive.</p>
<p>Synchronize with object layers can only be enabled with soluble supports (contact Z distance 0). </p>
<p>Not synchronizing with object layers allows the support layers to grow faster than the object layers (if not excessively slowed down by the cooling logic) and independent layer height also allows PrusaSlicer to follow the gap between the object and the support top surface precisely. We may consider this to be configurable even for non-soluble supports in the future.</p>
<p> </p>


Support material

Infill patterns

<p>Updating the firmware is <strong>recommended for all users</strong> as every new version brings new features and fixes.</p>
<div class="tip-callout"><strong>To utilize the new SuperPINDA, your MK3S must at least have firmware version 3.9.2!</strong></div>
<p>To flash the firmware onto your printer, you need:</p>
<ul>
<li>Computer running Windows, macOS, or Linux</li>
<li>USB cable, preferably the original included with your printer</li>
<li>PrusaSlicer and the printer's driver installed (download <a href="https://www.prusa3d.com/drivers/" target="_blank" rel="noopener noreferrer">here</a>)</li>
</ul>
<p>To check which firmware version you already have on your printer, power it up and go to <em>LCD menu -&gt; Support</em>. Scroll down and you will see the firmware version<strong>. The procedure for installing an older version of the firmware (downgrading) is exactly the same.</strong></p>
<div class="warning-callout">If you want to flash the firmware, the printer must be <strong>on</strong>.</div>
<h3><strong>Preparations</strong></h3>
<ul>
<li><strong>PrusaSlicer and the printer's driver must be installed.</strong> If you do not have this installed, it is found in the Drivers and Apps package available where you download the latest firmware.</li>
<li>Enter our <a href="https://www.prusa3d.com/drivers/">our downloads section</a> and download the firmware (<span style="color: #2dc26b;">green square</span>). To find the correct firmware, see the name and picture of the printers/upgrades and compare it to your machine. <strong>Be aware that Original Prusa MK3 and MK3S do not use the same firmware file. <em>However, MK3S and MK3S+ use the same firmware.</em></strong><br /><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/b54017457c98b323_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/b54017457c98b323_painted-600x348.jpeg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/b54017457c98b323_painted-800x464.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/b54017457c98b323_painted-300x174.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/b54017457c98b323_painted-768x445.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/b54017457c98b323_painted-1536x890.jpeg 1536w" alt="" width="600" height="347" loading="lazy" /></li>
</ul>
<h3>Flashing procedure</h3>
<ol start="1">
<li>To flash the firmware into your printer, connect the RAMBo board to your computer using the square-shaped <strong>USB-B 2.0 cable</strong>. The printer must be ON!</li>
</ol>
<p><img decoding="async" style="max-height: 400px; margin-left: auto; margin-right: auto; display: block;" src="https://cdn.help.prusa3d.com/wp-content/uploads/prusuki/prusuki-images/image.png" width="600" height="238" loading="lazy" data-hd-height="400px" data-hd-align="left" /></p>
<ol start="2">
<li>Unzip the .zip-file to a folder on your computer.</li>
<li>Open PrusaSlicer, navigate to <em>Menu -&gt; Configuration -&gt; Flash printer firmware</em>.</li>
<li>Click on the <strong>Browse</strong> button (<span style="color: #2dc26b;">green arrow <span style="color: #000000;">right picture</span></span>) and choose the .hex file from the location you <strong>unzipped</strong> it. <em>The file name with the firmware for the MK3S is <strong>prusa3d_fw_MK3S_x_x_x_xxx</strong> where the <strong>x</strong> is the firmware version number.</em></li>
<li>Make sure the Serial Port field (<span style="color: #e03e2d;">red square <span style="color: #2dc26b;"><span style="color: #000000;">right picture</span></span></span>) displays your printer's name (Original Prusa i3 MK3) and has a COM port assigned (ex. COM4). Click <span class="key">Flash!</span> and let the procedure complete. <em>Progress is indicated on both the Firmware flasher and the printer's display. </em></li>
</ol>
<table style="border-collapse: collapse; width: 100%; border-style: none; height: 20.8889px;" border="1">
<tbody>
<tr style="height: 20.8889px;">
<td style="width: 48.8562%; height: 20.8889px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/08/66a97389197dc3be280ff30399006134.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="How to update firmware (MK3S+/MK3S/MK3)" alt="" width="395" height="196" loading="lazy" /></td>
<td style="width: 48.8562%; height: 20.8889px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/08/67b0e83baf3aaf6f2844af3e532b9356.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="How to update firmware (MK3S+/MK3S/MK3)" alt="" width="395" height="196" loading="lazy" /></td>
</tr>
</tbody>
</table>
<div class="warning-callout">If the Serial port field display anything but the name of the printer (ex. usbmodemfa141 or /dev/tty.<em>usbmodem</em>) you should try another USB port on your computer, reinstall the driver or restart your computer.</div>
<div>
<h3>Problems when flashing</h3>
<div>If you encounter any firmware updating or flashing problems, check our article about the most common errors: <a href="http://help.prusa3d.com/article/firmware-updating-issues-mk2-5s-mk3s-mmu2s-mmu3_2225">Firmware updating issues (MK2.5S/MK3S+/MMU2S/MMU3)</a>.</div>
</div>

How to update firmware (MK3S+/MK3S/MK3)

The Original Prusa i3 MK3S+ is the successor of the award-winning Original Prusa i3 MK2S 3D printer.

Original Prusa i3 MK3S+ kit assembly

Original Prusa i3 MK3/MK3S to MK3S+ upgrade

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Basic calibration

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What to do when the printer reports an error message during calibration.

Calibration Error Messages

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

Calibration

Printer description

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

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Printer maintenance

Prusa Connect & PrusaLink

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

Using the printer

Print Quality Troubleshooting

Printer troubleshooting

Print Error Messages

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

Troubleshooting

Nozzles

Octoprint

Learn about different nozzles, Raspberry Pi connection, Octoprint and more.

3rd party accessories & Other projects

About PrusaSlicer

Configuration and profiles

User interface

Input/output

Left toolbar

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Other (PrusaSlicer)

The official documentation for the PrusaSlicer slicing software. From basic configuration to advanced settings like modifier meshes.

PrusaSlicer

1. Introduction

2A. MK3 Extruder disassembly

2B. MK3S Extruder disassembly

2A. Y-axis assembly

3A. MK3 Extruder upgrade

2B. Y-axis assembly

3B. MK3S Extruder upgrade

3. X-axis assembly

4. Electronics assembly

4. Z-axis assembly

5. Y-axis upgrade

5. E-axis assembly

6. Preflight check

6. LCD assembly

7. Heatbed & PSU assembly

8. Electronics assembly

9. Preflight check

Manual changelog MK3S+ kit

<p>Loose belts would cause a printer to malfunction and prevent proper printing. It can cause <a href="http://help.prusa3d.com/article/layer-shifting_2020">Layer shifting</a>, <a href="http://help.prusa3d.com/article/ghosting_1801">Ghosting</a>, or other print abnormalities like getting an irregular shape instead of a perfect circle when printing a cylinder. <strong>The Y-axis belt is located under the heatbed, X-axis belt moves the print head. All adjustments are done with the 2.5mm Allen key. </strong></p>
<h3>Checking belt tension</h3>
<h4>New procedure - Belt tuner app</h4>
<p>Follow the instructions in the video below, to adjust the belt tightness using our <a href="https://belt.connect.prusa3d.com/">belt tuner</a>. </p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/05/342c4a2c9bf82513.jpg" alt="" width="500" height="375" loading="lazy" /></p>
<p style="text-align: center;"><iframe src="https://www.youtube.com/embed/oeq2MVxE_H8" width="560" height="314" allowfullscreen="allowfullscreen" loading="lazy"></iframe></p>
<h4>Old procedure</h4>
<p>On MK3/S/+, it is possible to check the <strong>Belt Status</strong> numbers via <em>LCD Menu -&gt; Support -&gt; Belt Status</em>. </p>
<p><span style="color: #000000;">While there is not a precise ideal value, from our experience, the best approximate value is around 250 on the X-axis, and 275 on the Y-axis, with an optimal range at +-15 from these values on either axis. </span></p>
<p><span style="color: #000000;">The value does not represent a physical quantity, but an arbitrary number inversely proportional to the motor load. The values are with the consideration that the assembly is good and that the parts are in good condition and properly lubricated. Values may not be accurate if there are other problems. </span></p>
<ul>
<li>If your value is <strong>under</strong> (or close to) 240, you need to <strong>loosen</strong> the belt</li>
<li>If your value is <strong>over</strong> (or close to) 290, you need to <strong>tighten</strong> the belt</li>
<li>The values are updated every time you run the Selftest or run the belt test in <em>LCD menu -&gt; Calibration -&gt; Belt test</em>. </li>
</ul>
<p><span style="color: #000000;">Other MK-series models</span> do not have the belt status option. The clue we can give you is that the belt should sound roughly like a low bass string when plucked. It should be possible to pinch the two sides together with your thumb and index finger, but you should feel a little bit of resistance.</p>
<div class="warning-callout">The plastic parts holding the belts can get loose over time.</div>
<p>Another way is to use the technique described in <a href="http://help.prusa3d.com/guide/5-e-axis-assembly_28536#30816">this step</a> of the assembly manual to test if the pulley is correctly tightened and if the belt is not too loose. Hold the X-axis motor shaft with pliers (take advantage of the flat part of the shaft) to fix it in place (<strong><span style="color: #b96ad9;">purple circle</span></strong>), then try to move the extruder by hand. <strong>You should see no slack on the belt as a result of pushing on the extruder.</strong> The same procedure can be applied to test the Y-axis pulley and belt.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/prusuki/prusuki-images/2019-08-21-16-07-05-f-jmg-pa-bdtv-ruqf-11-full-1600-1200.jpg" alt="" width="600" height="415" loading="lazy" /></p>
<h3>X-axis belt</h3>
<h4>Slight adjustments MK3S</h4>
<p>Loosen the two front-facing screws and make sure they have space to their right to move (<span style="color: #f1c40f;"><strong>yellow circles</strong></span>). While assisting with the rotation of the motor with your hand, tighten the M3x18 screw on top of the X-end-motor (<span style="color: #b96ad9;"><strong>purple arrow</strong></span>).</p>
<p>After each turn or two check the tension in the belt by pressing them together. For optimal performance, the belt must need some force to press together with your fingers (<span style="color: #2dc26b;">green arrows</span>). <strong>Move the extruder all the way to the X-end-idler and try the belt tension in the middle of the X-axis.</strong></p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/d1a9b24b68e0121e_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/d1a9b24b68e0121e_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/d1a9b24b68e0121e_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/d1a9b24b68e0121e_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/d1a9b24b68e0121e_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/d1a9b24b68e0121e_painted-1536x1152.jpeg 1536w" alt="" width="600" height="450" loading="lazy" /></p>
<h4>Slight adjustments MK3S+, MK3.5/S, MK3.9/S, MK4/S</h4>
<ol>
<li>Slightly release all the screws holding the motor, otherwise, the "tensioner" won't work as the motor must be able to move (left picture).</li>
<li>Using the ball end of the Allen key, start tightening the screw on the rear side of the X-end-motor, but after each turn or two check the tension in the belt (right picture).</li>
<li>When you achieve optimal tension, please tighten the screws again (left picture).</li>
</ol>
<table style="border-collapse: collapse; width: 100%;" border="0">
<tbody>
<tr>
<td style="width: 48.805%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/da45b9e5fe1a6ec4_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/da45b9e5fe1a6ec4_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/da45b9e5fe1a6ec4_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/da45b9e5fe1a6ec4_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/da45b9e5fe1a6ec4_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/da45b9e5fe1a6ec4_painted-1536x1152.jpeg 1536w" alt="" width="400" height="300" loading="lazy" /></td>
<td style="width: 48.9057%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/4d946176a9a518fc_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/4d946176a9a518fc_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/4d946176a9a518fc_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/4d946176a9a518fc_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/4d946176a9a518fc_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/11/4d946176a9a518fc_painted-1536x1152.jpeg 1536w" alt="" width="400" height="300" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h4>Large adjustments MK3/S/+ or MK3.5/S</h4>
<p>If a slight adjustment is not sufficient you must adjust it at the belt holder. This is found on the back of the extruder and requires a little disassembly.</p>
<p>First, remove the two top screws from the motor-holder to let the belt have some slack in order to easier manipulate the belt.</p>
<ol>
<li>Snip the zip-ties on the back of the extruder (<span style="color: #e03e2d;"><strong>red arrows</strong></span>), which are securing the hotend wires <strong>and</strong> the ones securing the cable wrap.</li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/Adjusting-belt-tension-MK3S-03.png" alt="" width="600" height="450" loading="lazy" /></p>
<ol start="2">
<li style="counter-increment: li 1;">Unscrew the 4 screws circled in the picture below.</li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/Adjusting-belt-tension-MK3S-04.png" alt="" width="600" height="450" loading="lazy" /></p>
<ol start="3">
<li style="counter-increment: li 2;">Carefully pull the back plate loose, making sure the wires are safe, and turn the whole plate to the left or right.</li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/Adjusting-belt-tension-MK3S-05.jpg" alt="" width="600" height="574" loading="lazy" /></p>
<ol start="4">
<li style="counter-increment: li 3;">You now have access to where you mount the belts. Put a mark on the belt with a pen or marker as close to the plastic part as possible, so you know how it was adjusted. Now, take out the belt from the mount and move it in 1-2 teeth.</li>
</ol>
<div class="tip-callout">It may be necessary to cut off the last tooth of the belt.</div>
<ol start="5">
<li style="counter-increment: li 4;">Place the back plate back on, secure the screws, starting with the center one for alignment, then put on new zip-ties.</li>
<li>Re-tighten the screws on the x-motor, securing it. Adjust it tighter if needed.</li>
</ol>
<h4>Large adjustments MK4/S, MK3.9/S</h4>
<ol>
<li>Loosen the three indicated screws covering the X-carriage. Carefully take out the X-cover-back.
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/04/96f49f4aee27a2e4c92ed6d0dd7ff4c9_painted.jpeg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Adjusting belt tension (review)" alt="" width="600" height="400" loading="lazy" /></p>
</li>
<li>You now have access to where you mount the belt. Put a mark on the belt with a pen or marker as close to the plastic part as possible, so you know how it was adjusted. Now, take out the belt from the mount and move it in 1-2 teeth.</li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/04/5d0b7637d19fdb682ff706171280e0fb.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Adjusting belt tension (review)" alt="" width="600" height="450" loading="lazy" /></p>
<h3>Y-axis belt</h3>
<h4>Slight adjustments</h4>
<p>On the front plate of the printer's frame, behind the LCD module, you will find the printed Y-axis belt idler. This is held by two M3X10 screws (<span style="color: #b96ad9;"><strong>purple arrow</strong></span>), going through the front plate.</p>
<p>If you have a gap between the idler part and the front plate of the frame (<span style="color: #236fa1;"><strong>blue arrows</strong></span>) you can tighten the belt by using your 2.5 mm Allen key to turn the screws clockwise (<span style="color: #b96ad9;"><strong>purple arrow</strong></span>), closing the gap.</p>
<p>The easiest way to access the screws is from below, by moving the printer to the edge of its table, with the LCD module sticking out. You now have access to the bolts from below the LCD module.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-583x400.jpeg 583w, https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-800x549.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-300x206.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-768x527.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-1536x1053.jpeg 1536w" alt="" width="600" height="411" loading="lazy" /></p>
<h4>Large adjustments</h4>
<p>If a slight adjustment is not sufficient you must adjust it at the belt holder. There are two main types of the Y-axis belt holder, one adjustable and one fixed. The adjustable belt holder was introduced in the first quarter of 2019, with the S-upgrade for the Original Prusa MK3, and is also featured on the Original Prusa MK4. Adjustments for this are explained in '<strong>Method 1</strong>'. For an earlier Original Prusa MK3, follow '<strong>Method 2</strong>', for the fixed belt holder.</p>
<h4>Method 1 - Adjustable belt holder</h4>
<div class="tip-callout">The Original Prusa MK4/S has a different design than in the pictures, but the procedure is the same. </div>
<ol>
<li>Unplug the printer and lay it over on the side of the PSU.</li>
<li>Below the bed carriage, you will find the belt holder. Loosen the right screw by turning it <strong>counterclockwise</strong> (<span style="color: #e67e23;"><strong>orange circle</strong></span> left picture).</li>
<li>Turn the screw going through the two halves of the belt holder (<span style="color: #b96ad9;"><strong>purple arrow</strong></span> right picture). Turn <strong>clockwise</strong> to tighten the belt, moving the two halves together (<span style="color: #236fa1;"><strong>blue arrows</strong></span>).</li>
<li>When at the correct tension, secure the right half of the belt holder again by turning the screw from step 2 clockwise (<span style="color: #e67e23;"><strong>orange circle</strong></span> left picture).</li>
</ol>
<table style="border-collapse: collapse; width: 100%;" border="0">
<tbody>
<tr>
<td style="width: 48.8106%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/b0f4fab2c260d687_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/b0f4fab2c260d687_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/b0f4fab2c260d687_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/b0f4fab2c260d687_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/b0f4fab2c260d687_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/b0f4fab2c260d687_painted-1536x1152.jpeg 1536w" alt="" width="400" height="300" loading="lazy" /></td>
<td style="width: 48.8106%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/fdec3d592f278afe_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/fdec3d592f278afe_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/fdec3d592f278afe_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/fdec3d592f278afe_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/fdec3d592f278afe_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/fdec3d592f278afe_painted-1536x1152.jpeg 1536w" alt="" width="400" height="300" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h4>Method 2 - Fixed belt holder</h4>
<ol>
<li>Unplug the printer and lay it over on the side of the PSU.</li>
<li>Detach the belt-idler in order to easier manipulate the belt (<strong><span style="color: #b96ad9;">purple arrows</span></strong>). <em>Detaching the idler completely may not be necessary, but will make it easier to adjust the belt in the next step.</em></li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/e5390e0a76daf6dc_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/e5390e0a76daf6dc_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/e5390e0a76daf6dc_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/e5390e0a76daf6dc_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/e5390e0a76daf6dc_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/e5390e0a76daf6dc_painted-1536x1152.jpeg 1536w" alt="" width="600" height="450" loading="lazy" /></p>
<ol start="3">
<li style="counter-increment: li 2;">Set a mark on the belt so you know how much you are moving it. Now take out the belt of the top slot, and move it in 1-2 teeth (<strong><span style="color: #236fa1;">blue arrow</span></strong>) before pushing it back into the slot (<strong><span style="color: #2dc26b;">green arrows</span></strong>).</li>
</ol>
<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/10714ac443ad0a9c_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/10714ac443ad0a9c_painted-533x400.jpeg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/10714ac443ad0a9c_painted-800x600.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/10714ac443ad0a9c_painted-300x225.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/10714ac443ad0a9c_painted-768x576.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/10714ac443ad0a9c_painted-1536x1152.jpeg 1536w" alt="" width="600" height="450" loading="lazy" /><em>Your belt mount may look slightly different, being another iteration, but the procedure remains the same.</em></p>
<ol start="4">
<li style="counter-increment: li 3;">Re-attach the belt-idler with its two M3x10 screws through the frame (<strong><span style="color: #b96ad9;">purple arrow</span></strong>). Leave a gap with the frame, for slight adjustments (<strong>blue arrows</strong>). </li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-583x400.jpeg 583w, https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-800x549.jpeg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-300x206.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-768x527.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/73fa58fb081ffbfa_painted-1536x1053.jpeg 1536w" alt="" width="600" height="411" loading="lazy" /></p>

Adjusting belt tension (MK4/S, MK3.9/S, MK3.5/S, MK3/S/+)

<p>The Original Prusa MK2.5/S, MK3/S/+, and MK3.5/S use the E3D V6 Hotend. Any nozzle that is compatible with the E3D V6 Hotend can be installed on it. The stock nozzle that accompanies the printer is an E3D V6 0.4 mm brass nozzle, but other types and <a href="https://blog.prusaprinters.org/everything-about-nozzles-with-a-different-diameter_8344/">diameters</a> can be used as well. <strong>The following procedure applies to all nozzles, except the Olsson Ruby.</strong></p>
<div class="warning-callout"><strong>To replace the Olsson Ruby nozzle,</strong> follow the instructions on the <a href="https://support.3dverkstan.se/article/66-the-olsson-ruby-instructions-for-use">official 3DVERKSTAN website</a>. Otherwise, you could damage it!</div>
<h3>Why change the nozzle?</h3>
<p>There might be two main reasons for replacing the nozzle:</p>
<ul>
<li>The nozzle is worn out and needs a replacement.</li>
<li>You want to print using a different nozzle type, and/or diameter.</li>
</ul>
<div class="tip-callout">Unless you print abrasive materials with a brass nozzle, the stock brass nozzle will last you many hundreds of printing hours. Changing a relatively new nozzle to resolve a clog is not the solution!</div>
<div>The stock 0.4mm Nozzle installed on the Original Prusa i3 printers <a href="https://www.prusa3d.com/product/nozzle-e3d-v6-0-4-mm/">can be found in the eshop</a>. We also offer <a href="https://www.prusa3d.com/product/nozzle-0-4/">an alternative 0.4mm nozzle</a> compatible with i3 and MINI/+ printers.</div>
<h3>Tools necessary</h3>
<ul>
<li>2.5 mm Allen key (Included with assembled printers and kits)</li>
<li>7 mm spanner/socket or pliers (7 mm spanner/socket not included with assembled printers and kits)</li>
<li>17 mm spanner (not included with assembled printers and kits)</li>
<li>Small plate or aluminium foil (not included with assembled printers and kits)</li>
</ul>
<h3>Procedure</h3>
<p>The following procedure assumes that a firmware version from 3.12.0 or above is installed. In case your printer has a previous firmware version, we recommend <a href="http://help.prusa3d.com/article/how-to-update-firmware-mk3s-mk3s-mk3_2227">upgrading to the latest version</a>. If you did not flash a newer firmware version, follow the procedure, except for "Step 3 alternative" instead of step 3.</p>
<div class="note-callout"><strong>Follow this procedure exactly!</strong> Omitting steps can cause leaking and extrusion issues outlined at the end of this article.</div>
<ol start="1">
<li>Unload the filament, if it is loaded, from <em>LCD Menu -&gt; Unload Filament</em>. Optionally, perform a <a href="http://help.prusa3d.com/article/cold-pull-mk3-s-mk2-5-s-mk3-5-s_2075">Cold pull (MK3/S/+, MK2.5/S, MK3.5/S)</a>.</li>
<li>On <strong>MK2.5/S</strong> and <strong>MK3/S/+</strong>, navigate to <em>LCD Menu -&gt; Settings -&gt; HW Setup -&gt; Nozzle Change</em>.
<ol type="a">
<li>The printer will display a message with a link to this guide.</li>
<li><strong>Click the LCD encoder</strong>: the printer will auto-home, and subsequently move the Z axis to the topmost position, and the X axis to the center. In the meantime, the printer will automatically heat the nozzle to <strong>280 °C</strong>. Heating the nozzle is essential for this process.</li>
<li>Once the nozzle is at <strong>280 °C</strong>, the printer screen will display the following message: "<strong>Hotend at 280C! Nozzle changed and tightened to specs?</strong>". Do not click on the LCD encoder for now. 
<p>On <strong>MK3.5/S</strong>, gain better access to the nozzle by moving the extruder as high as possible, go to <em>LCD Menu -&gt; Control -&gt; Move Axis -&gt; Move Z</em>. Spin the <strong>Knob</strong> to adjust the height. Once this is done, preheat the nozzle to 280 °C from <em>LCD Menu -&gt; Control -&gt; Temperature -&gt; Nozzle Temperature</em>. </li>
</ol>
</li>
</ol>
<div class="warning-callout">CAUTION: Heated parts can cause severe burns!</div>
<ol start="3">
<li>Unscrew the two screws on the print fan and the single screw securing the fan shroud. Remove both parts (picture below).</li>
</ol>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2023/06/85adeda53781f1c8b8e5ad32a6c8d6c6.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Changing or replacing the nozzle (MK2.5S/MK3S/MK3S+) review" alt="" width="600" height="403" loading="lazy" /></p>
<ol start="4">
<li>Hold the heater block with a 17 mm spanner (M10) or adjustable wrench.</li>
</ol>
<div class="warning-callout">Be extra careful around the <strong>fragile</strong> hotend heater and thermistor wires. You can break them off or <strong>short-circuit the heater with your spanner!</strong></div>
<ol start="5">
<li>Unscrew the nozzle using the supplied pliers. If you are using the E3D nozzles from our online store, use a 7mm spanner (M4) or 7 mm socket. <strong>Be careful, the nozzle is still hot! Place it out of the way on your non-flammable surface.</strong></li>
<li>Make sure that the printer is still on the screen described in step 3c, and that the set temperature (280 °C) didn't change. Holding the heater block with your spanner, carefully screw the new nozzle in and tighten it gently, but firmly. <strong>Do not use excessive force!</strong></li>
</ol>
<div class="tip-callout">Our service and assembly teams use a torque wrench rated for 1 - 5 N m and <strong>tighten the nozzle with a force of 2.5 N m</strong> (Newton Meter).</div>
<h3>Final inspection</h3>
<p><strong>There must always be a gap (~0.5 mm)</strong> between the nozzle and the heater block (left picture). The nozzle must be tightened/secured in the heater block, and <strong>locked against the heat break</strong> while heated (right picture). Failing to do so will cause leaks (center picture).</p>
<div class="warning-callout"><strong>It is necessary to redo the <a href="http://help.prusa3d.com/article/first-layer-calibration-i3_112364">First Layer Calibration (i3)</a> after replacing the nozzle.</strong> If you installed a nozzle with a diameter other than 0.4 mm (0.25, 0.6, 0.8 mm), please see <a href="http://help.prusa3d.com/article/different-nozzle-types_2193#first-layer-calibration-of-other-nozzles">Different nozzle types</a>.</div>
<table style="border-collapse: collapse; width: 100%;" border="0">
<tbody>
<tr>
<td style="width: 39.2947%;"><img decoding="async" style="float: left;" src="https://cdn.help.prusa3d.com/wp-content/uploads/ljZASfpEuJDMIZZo_8643_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/ljZASfpEuJDMIZZo_8643_painted-300x300.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/ljZASfpEuJDMIZZo_8643_painted-400x400.jpeg 400w" alt="" width="300" height="300" loading="lazy" /></td>
<td style="width: 60.7053%;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/526a59ae1e9dcd1b_painted.png" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/526a59ae1e9dcd1b_painted-300x136.png 300w, https://cdn.help.prusa3d.com/wp-content/uploads/526a59ae1e9dcd1b_painted-600x272.png 600w, https://cdn.help.prusa3d.com/wp-content/uploads/526a59ae1e9dcd1b_painted-768x348.png 768w, https://cdn.help.prusa3d.com/wp-content/uploads/526a59ae1e9dcd1b_painted-800x363.png 800w" alt="" width="772" height="350" loading="lazy" /></td>
</tr>
</tbody>
</table>
<div class="tip-callout">You can find this procedure as <a href="https://youtu.be/txt6sxV6X88">a video on our YouTube channel</a>. Be aware that some steps may differ slightly from the procedure outlined here, and printed parts of the extruder may look a little different than yours.</div>


Changing or replacing the nozzle (MK2.5/S, MK3/S/+, MK3.5/S)

<p></p>
<p>A 'cold pull' is a technique that allows you to clean your printer’s nozzle and hotend from any material that may be stuck or burnt inside. You can also use it to clean your hotend during your usual maintenance routine.</p>
<div class="warning-callout">If you are using Nozzle X, <strong>do not</strong> use the cold-pull method, but only use cleaning filament.</div>
<p>The cold pull should be made if your nozzle is only partially clogged, and some filament is still being extruded. If the nozzle is completely clogged, please check the <a href="http://help.prusa3d.com/article/clogged-nozzle-hotend-mk3-5-s-mk3s-mk2-5s_2008">Clogged nozzle guide</a>.</p>
<div class="tip-callout">Our testing has found that <strong>PLA works best for a cold pull,</strong> as other filaments do not retain the tip as PLA does and they will either tear or melt too much. However, there are filaments specifically made for cleaning hotends.</div>
<h3>Procedure</h3>
<ol>
<li>Go to the <em>LCD Menu -&gt; Settings -&gt; Temperature -&gt; Nozzle</em> (MK2.5/S, MK3/S/+) / <em>LCD Menu -&gt; Control -&gt; Temperature -&gt; Nozzle </em>(MK3.5/S), and set the temperature to 270 °C.</li>
<li>While waiting for the nozzle to reach the temperature, toggle the <strong>Filament autoload</strong> off in the <em>LCD Menu -&gt; Settings -&gt; Fil. sensor -&gt; F. autoload </em>(MK2.5/S, MK3/S/+) / <em>LCD Menu -&gt; Settings -&gt; Filament sensor </em>(MK3.5/S).</li>
<li>Still being in the <em>Menu</em>, go to <em>Settings</em> and choose <em>Disable steppers </em>(MK2.5/S, MK3/S/+). On MK3.5/S, navigate to <em>Control -&gt; Disable motors</em>. <br /><em>There is no message of the steppers being disabled, but you may hear an electrical hiss disappear when selected. <strong>If you can move the bed or extruder on its axis by hand, they are disabled.</strong></em></li>
<li>Open the Extruder Idler door. <em>Unscrew the screws circled below using a 2.5 mm Allen key. On the MMU2S and MMU3, unscrew the Bowden PTFE tube that connects the MMU unit with the extruder.</em></li>
</ol>
<table style="border-collapse: collapse; width: 100%;" border="0">
<tbody>
<tr>
<td style="width: 48.805%;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/idler2.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/idler2-300x300.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/idler2-400x400.jpg 400w, https://cdn.help.prusa3d.com/wp-content/uploads/idler2-768x768.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/idler2-600x600.jpg 600w" alt="" width="400" height="399" loading="lazy" /></td>
<td style="width: 48.9057%;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/mmus2.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/mmus2-300x216.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/mmus2-554x400.jpg 554w, https://cdn.help.prusa3d.com/wp-content/uploads/mmus2-768x554.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/mmus2-800x577.jpg 800w" alt="mmu" width="400" height="290" loading="lazy" /></td>
</tr>
</tbody>
</table>
<ol start="5">
<li>Once it has reached 270 °C, insert PLA filament manually into the extruder and push it in until it starts pouring out of the nozzle.</li>
<li>Stop heating by pressing <em>Cooldown</em> in the <em>LCD Menu -&gt; Preheat</em> (scroll all the way down), or by pressing the reset (X) button. Let the nozzle temperature drop to room temperature. To speed up the cooling you can engage the print fan at full speed, from<em> LCD menu -&gt; Settings/Control -&gt; Temperatures -&gt; Fan speed -&gt; [255].</em></li>
<li>Continue manually pushing the filament down until the temperature is too low for it to melt and come out (around 170 °C for PLA). <em>The nozzle has to be filled for the cold pull to be successful.</em></li>
<li>Pick away extruded material so there is nothing obstructing the pull later on.</li>
<li>After the nozzle cools down to the room temperature, go again to the <em>LCD Menu -&gt; Settings/Control -&gt; Temperature -&gt; Nozzle</em> and set the temperature to 85 °C.</li>
<li><strong>As soon as the extruder reaches this temperature</strong>, grab the filament with pliers and pull it slowly but steadily out of the extruder. <em>The filament can break inside. Make sure to pull straight upwards, not sideways. Hold the extruder with your other hand.</em></li>
<li>Don't stop until the filament is completely pulled out from the extruder.</li>
</ol>
<h3>Results</h3>
<p>On the tip of the filament that has been pulled out, you may see remnants of the previous material(s) you have been using or some burnt dirt that has settled in the nozzle (left picture). You might want to repeat this procedure several times until the filament comes out clean.</p>
<p>The right picture shows what a clean cold-pulled filament should look like. It is important to have the imprint of the nozzle on it, this way you are sure the nozzle was filled and nothing was left inside. Also, the color is not mixed with the one you have been using previously or have dark marks on it.</p>
<table style="border-collapse: collapse; width: 100%;" border="0">
<tbody>
<tr>
<td style="width: 48.805%;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/dirty-cold-pull.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/dirty-cold-pull-300x214.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/dirty-cold-pull-561x400.jpg 561w, https://cdn.help.prusa3d.com/wp-content/uploads/dirty-cold-pull-768x548.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/dirty-cold-pull-800x571.jpg 800w" alt="dirty cold pull" width="400" height="286" loading="lazy" /></td>
<td style="width: 48.9057%;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/clean-cold-pull.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/clean-cold-pull-300x203.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/clean-cold-pull-591x400.jpg 591w, https://cdn.help.prusa3d.com/wp-content/uploads/clean-cold-pull-768x520.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/clean-cold-pull-800x542.jpg 800w" alt="clean cold pull" width="693" height="469" loading="lazy" /></td>
</tr>
</tbody>
</table>
<h3>After the procedure</h3>
<p>Secure the idler door by having <strong>the head of the idler screw</strong>, on the left of the extruder, <strong>about flush with the plastic parts, when the filament is not loaded.</strong> Then we recommend running the Z calibration as pushing on the extruder might have thrown it off balance. Also, turn the filament sensor/filament autoload back on.<br />On MK2.5/S and MK3/S/+, the Z-axis calibration is found in <em>LCD menu -&gt; Calibration -&gt; Calibrate Z</em>).<br />On MK3.5/S, the Z-axis calibration is found in <em>LCD menu -&gt; Control -&gt; Calibrations &amp; tests -&gt; 3. Z alignment calibration</em>.</p>
<div class="note-callout">Please see <a href="http://help.prusa3d.com/article/under-extrusion_2007">this article</a> to learn about the most common causes leading to filament extrusion problems and how to prevent them from happening.</div>

Cold pull (MK3/S/+, MK2.5/S, MK3.5/S)

<p>It is recommended to regularly take some time to maintain your printer. This should be done even if the printer is working perfectly. <strong>The inspection and maintenance of its various components should be done every couple of hundred hours of print-time.</strong> This guide is valid for all the Original Prusa i3 printers, i.e. MK3S+, MK3s, MK3, MK2.5S, MK2.5, MK2S, and Plus 1.75 mm.<strong><br /></strong></p>
<div class="tip-callout">You can check the number of printing hours from your printer in the <em>LCD menu - Statistics</em>.</div>
<div><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/fullwithdesc.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/fullwithdesc-562x400.jpg 562w, https://cdn.help.prusa3d.com/wp-content/uploads/fullwithdesc-800x570.jpg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/fullwithdesc-300x214.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/fullwithdesc-768x547.jpg 768w" alt="" width="703" height="500" loading="lazy" /></div>
<h3>Useful tools:</h3>
<p><strong>Besides the usual tools, such as Allen keys, needle-nose pliers, and IPA + paper towels, you might need:</strong></p>
<ul>
<li><strong>Lubricant:</strong> the best option is the Prusa lubricant. One is sent with the printer, but it can also be found in our <a href="https://www.prusa3d.com/product/prusa-lubricant-applicator-set-5g/">e-shop</a>. Other recommended lubricants are Super Lube 210XX, GLEIT-µ HF 400, and Mogul LV 2-EP. We do not recommend lubricants with a very high viscosity.</li>
</ul>
<div class="warning-callout"><strong>Do not apply lubricant on the trapezoid nuts or the threaded lead screws of the Z-axis!</strong></div>
<ul>
<li><strong>Compressed air:</strong> also known as canned air. Be sure to not hold it upside down while spraying - otherwise, you could damage any electronic components while trying to clean them.</li>
<li><strong>Brush:</strong> a small brass brush is an ideal tool for cleaning the Bondtech filament pulleys. If you don't have a brass brush any brush with hard bristles will do the job. Alternative: You can use the acupuncture needle that comes with the printer or a toothpick.</li>
</ul>
<h3>Axes check</h3>
<p><strong>What to check on your printer:</strong></p>
<ul>
<li><span style="color: #000000;"><strong>Smooth rods:</strong> scratches/grooves - take each rod between two/three fingers and move them slowly from one end of the rod to another, while rotating the fingers around the rod. If you notice any scratch, verify it with your fingernail. </span></li>
<li><strong>Bearings:</strong> Clean and lubricate the bearings and rods as shown <a href="http://help.prusa3d.com/guide/maintenance-tips_23200">this guide</a>. Despite cleaning and lubricating the smooth rods, it can happen that the axes' movement is still not smooth. In this case, please remove the bearings from the printer and lubricate them from the inside with a pea-sized amount of lubricant.</li>
</ul>
<div class="tip-callout">Screws on the back of the extruder (X-carriage-back) or the U-bolts, should NOT be overtightened, as this might deform the bearings and cause scratches on the smooth rods.</div>
<ul>
<li><span style="color: #000000;"><strong>Belt pulleys:</strong> any debris around the belt pulleys and belts should be immediately removed to ensure smooth operations. Also, check if the set screw of the belt pulley is firmly secured on the flat side of the motor shaft.</span></li>
<li><span style="color: #000000;"><strong>Idler screw</strong> (M3x40 with the spring on it) is not overtightened or too loose. Generally, the head of the screw, on the left side, should be about flush with the printed parts of the extruder. Details on the ideal tension of the idler screw can be found in <a href="http://help.prusa3d.com/article/idler-screw-tension_177367">Idler screw tension</a>.</span></li>
<li><span style="color: #000000;"><strong>Y- and X-axis belts:</strong> Both of the belts should be tight enough to sound like a low bass note when plucked. On the MK3/S/+, the belt status can be checked in the <em>LCD menu - Support - Belt status</em>. Recommended values are between 260 and 290. For details on adjusting the belt tension <a href="http://help.prusa3d.com/article/adjusting-belt-tension-mk4-s-mk3-9-s-mk3-5-s-mk3-s_112380">please see this article</a>.</span></li>
</ul>
<h3>Flexible steel sheet</h3>
<div class="warning-callout">Acetone should be used sparingly for cleaning, and only be used on the Smooth steel sheet! <strong>Never use acetone on the Textured or Satin steel sheet</strong> as the surface will be permanently damaged.</div>
<div>All flexible steel sheets should be cleaned regularly to ensure adhesion, but the exact methods and washing solutions can differ depending on your type of sheet.</div>
<p>You can find more information on how to take care of your flexible steel sheet <a href="http://help.prusa3d.com/article/flexible-steel-sheets-guidepost_2195">in this article</a>.</p>
<h3>Fans</h3>
<p>The Original Prusa i3 MK3/S/+ can spot if any of the fans stop spinning. However, that does not mean you should not check them during maintenance. Dust or plastic build-up can decrease their efficiency or even damage them.</p>
<p>A cotton swab can also be used to clean off dust and debris from the propeller or canned air will clear the dust. Tweezers can be used to take out any plastic strands. <strong>Hold the propeller</strong> <strong>of the fan to prevent it from spinning while cleaning it with canned air</strong>. Otherwise, it can get damaged. Clear away any debris that may be stuck and check that it can rotate freely. </p>
<h3>Extruder driver gear</h3>
<p>The MK2.5/S and MK3/S/+ printers are equipped with two Bondtech gears, made of hardened carbon steel. One is the <strong>pulley gear,</strong> secured on the extruder's motor shaft by a set screw. The other is the <strong>idler gear</strong>, which spins freely mounted on the idler door. <strong>If you have had a clog, they can also have collected residue grinding the filament</strong> which will, in turn, reduce their grabbing force on the filament. </p>
<p><strong>Regular cleaning and lubrication will:</strong></p>
<ul>
<li>Reduce wear and noise.</li>
<li>Increase the grabbing force on the filament.</li>
<li>Lower friction between the two pulley gears.</li>
<li>Protect against rust. </li>
</ul>
<p>If you're cleaning the gear inside the extruder without removing the extruder motor first, be sure to cover the PTFE tube to avoid any debris falling in. You can use a cotton swab - it will reliably cover the tube without damaging it). After you're done cleaning, give it a good puff of air to clear any remains, while the PTFE tube is still covered.</p>
<p>Open the Extruder idler door by releasing the screw(s) on the left side of your extruder.</p>
<ul>
<li>The <strong>MK3, and MK2.5</strong> extruders have <a href="http://help.prusa3d.com/article/idler-screw-tension_177367">two idler screws</a>.</li>
<li>The <strong>MK3S/+ and MK2.5S</strong> extruders have <a href="http://help.prusa3d.com/article/idler-screw-tension_177367">one idler screw</a>.</li>
</ul>
<p>Both hobbed gears can have a build-up of filament shavings stuck in the grooves. Using a brass brush, clean what you can, then rotate the gear a few degrees and repeat until you do a full turn. They can also be cleaned one at a time using the acupuncture needle that comes with the printer.</p>
<p>The gears can be covered by rust. There is no need to worry. The gears themselves should not be damaged. Remove any problematic bits of filament and clean them with a brush. </p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/bontechgear.jpg" sizes="100vw" srcset="Bondtech gears on an MK3" alt="bontech gears" width="498" height="350" loading="lazy" /></p>
<p>Make sure the Bondtech pulley gear is aligned with the path of the filament and secured on the flat side of the motor shaft. Also, check that the shaft of the idler gear goes through both "ears" of the Extruder-Idler-door plastic part and spins freely. You can find a more detailed guide in <a href="http://help.prusa3d.com/article/checking-re-aligning-the-bondtech-gear-mk3-5-s-mk3s-mk2-5s_133176">Checking/re-aligning the Bondtech gear (MK3.5/S, MK3S/+, MK2.5S)</a>.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign-300x290.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign-413x400.jpg 413w, https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign-768x743.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign-620x600.jpg 620w" alt="" width="413" height="400" loading="lazy" /></p>
<p>Apply a tiny amount of the grease only to the teeth protruding outwards from the gear. <strong>Make sure that the lubricant never gets in contact with the filament teeth.</strong> Do not use oil-based lubricant as it may spread to unwanted sections, like where the filament is fed into the hotend.</p>
<p><span style="color: #000000;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/iddlegear.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/iddlegear-300x134.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/iddlegear-600x267.jpg 600w" alt="idlegear" width="618" height="275" loading="lazy" /></span></p>
<h3>Electronics</h3>
<p><strong>On the MK2/S and MK2.5/S</strong> - Check and reconnect the electrical connectors on the <a href="http://help.prusa3d.com/article/mini-rambo-electronics-wiring-mk2s-mk2-5-mk2-5s_2109">miniRAMBo board</a> <strong>after the first 50 hours of printing and then every 150-200 hours.</strong></p>
<p><strong>On the MK3/S/+</strong> - Check and reconnect the electrical connectors on the <a href="http://help.prusa3d.com/article/einsy-rambo-electronics-wiring-mk3-mk3s-mk3s_2107">EinsyRAMBo board</a> <strong>every 600 - 800 hours of printing.</strong></p>
<div class="warning-callout">Before touching the electrical connections, please make sure that the printer is off, and unplugged from the main power source.</div>
<ul>
<li>Check if there are any pinched or worn cables on the printer.</li>
<li>Open the electronics casing and blow compressed air in between the cables to get rid of dust.</li>
<li>Check the connection of all of the wires on the <a href="http://help.prusa3d.com/article/mini-rambo-electronics-wiring-mk2s-mk2-5-mk2-5s_2109">mini RAMBo board</a> or <a href="http://help.prusa3d.com/article/einsy-rambo-electronics-wiring-mk3-mk3s-mk3s_2107">EINSY RAMBo board</a>. Especially pay attention to the cables from the PSU (power source) and heaters. Make sure they are inserted all the way in and well-tightened.</li>
<li><span style="color: #000000;">Users of the <strong>Original Prusa i3 MK2/S </strong>and <strong>MK2.5/S</strong> need to pay special attention to the printer's power-input and heatbed's power connectors. Make sure both the connector and socket are not damaged in any way.</span></li>
<li><span style="color: #000000;">Users of the <strong>Original Prusa i3 MK3/S/+</strong> should lightly tug the power and heatbed connectors. If any movement is felt, then re-tighten the screws.</span></li>
</ul>
<h3>Nozzle change</h3>
<p>Putting an exact number on how long a nozzle will last is very difficult, as it depends on how much you print, what types of filament you use, and how often you change between filament types. <strong>It is not the first thing you should look to if you are experiencing extrusion issues</strong>, but if the printer has been in use for more than 3-6 months and you are getting poor print quality, even after doing the mentioned maintenance, you may want to consider <a href="http://help.prusa3d.com/article/changing-or-replacing-the-nozzle-mk2-5-s-mk3-s-mk3-5-s_2069">replacing the nozzle</a>.</p>
<h3>Firmware and software</h3>
<p>You should always be using the latest <strong>stable</strong> firmware version that we have published for your specific printer model. You can check the firmware version you have in the <em>LCD menu - Support</em>.</p>
<ul>
<li><a href="http://help.prusa3d.com/article/how-to-update-firmware-mk3s-mk3s-mk3_2227"> See this article</a> to flash the fimware on your <strong>MK3/S/+</strong>.</li>
<li><a href="http://help.prusa3d.com/article/firmware-updating-mk2-5s-mk2s_155126">See this article</a> to flash the firmware of your <strong>MK2/S or MK2.5/S</strong></li>
</ul>
<p>We also recommend using the latest version of our <a href="http://help.prusa3d.com/article/install-prusaslicer_1903">PrusaSlicer</a>, as it enables you to <strong>enjoy all the features of your printer</strong>. It even saves information about the printer model, nozzle diameter, and firmware version directly into the g-code file so that the printer can warn you if anything is out of date or incompatible.</p>


i3 Printer Regular Maintenance

<p>As there are ways of remotely transferring files and starting prints, an SD card or USB flash drive is the most common and reliable way to get your files to your machine. Though common and convenient, flash memory is not the most reliable in itself and your storage can be corrupted or fill up without any obvious signs. Therefore, we have put together a small guide on how to maintain, format, and purchase memory for your Original Prusa printer.</p>
<h3>Make sure your SD card is not locked!</h3>
<p>The SD card has a latch on the side. Before using your SD card, make sure that the latch is not set to the Locked position. In case it is locked, you will not be able to save files on the card, and the printer will not be able to open the SD card.</p>
<p><img decoding="async" style="max-height: 350px; display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-01.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-01-300x293.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-01-410x400.jpg 410w" data-hd-height="350px" data-hd-align="center"></p>
<h3>Storage over 32 GB</h3>
<p>There is no upper size limit on compatible storage media, but <strong>the built-in Windows formatting tool does not support formatting storage media from a size of 32 GB or more to FAT32.</strong> It will only provide the option for exFAT, which is currently not supported by our printers. There are similar limitations under various versions of Apple's OSx, where a third-party application must be used to format it correctly.</p>
<p>To format such a drive you need a third-party application, like Rufus, FAT32 format, or EaseUS Partition Master. <strong>Be careful when using such programs</strong> so you do not <strong>accidentally format the wrong storage media</strong>, like your hard drive. However, 8-16 GB is more than enough for most use cases, as a G-code file rarely exceeds 100 MB.</p>
<h3>How do I format the USB drive/SD card?</h3>
<p>If your SD card or USB drive is full or if you can't read the content of the drive, but the drive is recognized by windows, most often all you need to do is to format the drive.</p>
<div class="note-callout">If your USB drive or SD card does not even show up in your computer file explorer it is probably corrupted beyond repair, or at least beyond the scale of this article. If you get an error like the one in the picture below and it does not show up anywhere, off to google you go, but you might have to consider this card/USB drive lost and get a new one.</div>
<p><img decoding="async" loading="lazy" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-02V3.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-02V3-600x238.jpg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-02V3-800x317.jpg 800w, https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-02V3-300x119.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-02V3-768x304.jpg 768w" alt="" width="631" height="250"></p>
<h3>How to format on Windows</h3>
<p>On Windows, this is very simple. Locate your USB drive or SD card in my computer, right-click, and choose format.</p>
<p><img decoding="async" style="max-height: 350px; display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-03.png" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-03-300x288.png 300w, https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-03-417x400.png 417w, https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-03-768x737.png 768w, https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-03-625x600.png 625w" data-hd-height="350px" data-hd-align="center"></p>
<p>A new small window will pop up. Most of the time you can simply leave everything to default, but the most important thing is that the <strong>File System is set to FAT32.</strong> This and the Volume Label (Name of the drive) is the only thing you want to touch here. Click Start and your drive will be formatted in a matter of seconds.</p>
<div class="warning-callout">Formatting any drive will delete all the content of the drive! Back up your stuff!</div>
<p><img decoding="async" style="max-height: 300px; display: block; margin-left: auto; margin-right: auto;" title="https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-04-166x300.png 166w, https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-04-222x400.png 222w" src="https://cdn.help.prusa3d.com/wp-content/uploads/SD-cards-and-USB-flash-drives-04.png" data-hd-height="300px" data-hd-align="center"></p>
<div class="note-callout">If the USB stick will not work even after this procedure, it is either broken or its "partitioning scheme" is set as GPT, which is incorrect. <strong>It must be set as MBR (Master Boot Record).</strong> For how to change this, please see <a href="https://docs.microsoft.com/en-us/windows-server/storage/disk-management/change-a-gpt-disk-into-an-mbr-disk">Microsoft's official documentation</a>.</div>
<h3>How to format on Mac</h3>
<p>On Mac, it is a few more steps, but still very accessible. Again, you want to choose <strong>FAT32 as your file system</strong>, but you also have the option of changing the "partitioning scheme", which <strong>should always be MBR (Master Boot Record).</strong></p>
<div class="warning-callout">This process deletes all content from the drive.</div>
<ol>
<li>Plug the USB drive or SD card into your Mac.</li>
<li>Go to <em>Applications -&gt; Utilities</em> and launch <em>Disk Utility.</em></li>
<li>Click on the icon in the top-left (<span style="color: #2dc26b;">green arrow</span>) and select "Show All Devices" from the drop-down menu.</li>
</ol>
<p><img decoding="async" loading="lazy" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b49c3bac01f2fd71_painted.png" sizes="(min-width: 1024px) 820px, 100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b49c3bac01f2fd71_painted-600x271.png 600w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b49c3bac01f2fd71_painted-800x361.png 800w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b49c3bac01f2fd71_painted-300x135.png 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b49c3bac01f2fd71_painted-768x347.png 768w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b49c3bac01f2fd71_painted-1536x693.png 1536w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b49c3bac01f2fd71_painted.png 1600w" alt="" width="500" height="226"></p>
<p style="text-align: center;"><em>macOS Big Sur 11.6</em></p>
<ol start="4">
<li>Right-click on the USB drive/SD card in the sidebar under "External". <em>Select the top entry for your drive, not a partition located below.</em></li>
<li>Select Erase in the Disk Utility-toolbar (<span style="color: #b96ad9;">purple arrow</span>).</li>
</ol>
<p><img decoding="async" loading="lazy" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b04f0e7375dfbc17_painted.png" sizes="(min-width: 1024px) 820px, 100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b04f0e7375dfbc17_painted-600x271.png 600w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b04f0e7375dfbc17_painted-800x361.png 800w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b04f0e7375dfbc17_painted-300x135.png 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b04f0e7375dfbc17_painted-768x347.png 768w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b04f0e7375dfbc17_painted-1536x693.png 1536w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/b04f0e7375dfbc17_painted.png 1600w" alt="" width="500" height="226"></p>
<p style="text-align: center;"><em>macOS Big Sur 11.6</em></p>
<ol start="6">
<li>Enter a name for the formatted disk.</li>
<li>Click on the Format menu and choose MS-DOS (FAT).</li>
<li>Make sure the Scheme is set to "Master Boot Record".</li>
</ol>
<p><img decoding="async" loading="lazy" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/snmek-obrazovky-2021-10-07-v8-32-01.png" sizes="(min-width: 1024px) 820px, 100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/snmek-obrazovky-2021-10-07-v8-32-01-600x301.png 600w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/snmek-obrazovky-2021-10-07-v8-32-01-800x401.png 800w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/snmek-obrazovky-2021-10-07-v8-32-01-300x150.png 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/snmek-obrazovky-2021-10-07-v8-32-01-768x385.png 768w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/snmek-obrazovky-2021-10-07-v8-32-01-1536x771.png 1536w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/snmek-obrazovky-2021-10-07-v8-32-01-2048x1027.png 2048w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/10/snmek-obrazovky-2021-10-07-v8-32-01.png 1600w" alt="" width="500" height="251"></p>
<p style="text-align: center;"><em>macOS Big Sur 11.6</em></p>
<ol start="9">
<li>Click Erase.</li>
<li>Your USB drive will now be erased and re-formatted correctly.</li>
</ol>
<div class="tip-callout">If your SD card is not detected by the printer at all, be sure to check out <a href="http://help.prusa3d.com/article/sd-card-not-working_2095">SD card not working</a> for further information.</div>

SD cards and USB drives

<p>In case there is a clog in your hotend, the filament might grind against the Bondtech-gears and be damaged enough so it can't be unloaded. It might snap right above the PTFE-tube when you try to pull it out by hand. In this case, the filament will need to be removed manually.</p>
<h3>Idler door open</h3>
<p>Open the idler door by removing the spring-loaded tension-screw(s), on the left side of the extruder.</p>
<table style="border-collapse: collapse; width: 100%; height: 348px;" border="0">
<tbody>
<tr style="height: 331px;">
<td style="width: 50%; height: 331px;"><img decoding="async" style="max-height: 350px; display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu-533x400.jpg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu-768x576.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu-800x600.jpg 800w" width="400" height="300" loading="lazy" data-hd-height="350px" data-hd-align="center" /></td>
<td style="width: 50%; height: 331px;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/MK3.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/MK3-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/MK3-534x400.jpg 534w" alt="" width="400" height="300" loading="lazy" /></td>
</tr>
<tr style="height: 17px;">
<td style="width: 50%; height: 17px; text-align: center;"><strong>MK3S, MK3S+, MK3.5/S extruder (single idler screw)</strong></td>
<td style="width: 50%; height: 17px; text-align: center;"><strong>MK3 extruder (two idler screws)</strong></td>
</tr>
</tbody>
</table>
<div> </div>
<h4>MMU2S/MMU3 idler door</h4>
<div>On the MMU, due to the "chimney" (IR-sensor-holder-mmu2s), you must remove the whole idler door by unscrewing the hinge- screw (red arrow) on the back. </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/idlermmu2s.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/idlermmu2s-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/idlermmu2s-533x400.jpg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/idlermmu2s-768x576.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/idlermmu2s-800x600.jpg 800w" alt="" width="401" height="301" loading="lazy" /></div>
<h3>Where did it break?</h3>
<table style="border-collapse: collapse; width: 100%; height: 311px;" border="0">
<tbody>
<tr style="height: 294px;">
<td style="width: 50%; height: 294px;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0300.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0300-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0300-533x400.jpg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0300-768x576.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0300-800x600.jpg 800w" alt="" width="400" height="300" loading="lazy" /></td>
<td style="width: 50%; height: 294px;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0271.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0271-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0271-533x400.jpg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0271-768x576.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0271-800x600.jpg 800w" alt="" width="399" height="299" loading="lazy" /></td>
</tr>
<tr style="height: 17px;">
<td style="width: 50%; height: 17px; text-align: center;"><strong>Use Method 1</strong></td>
<td style="width: 50%; text-align: center; height: 17px;"><strong>Use Method 2</strong></td>
</tr>
</tbody>
</table>
<p>If the filament snapped right at the edge of the PTFE you should start with Method number 1, where you try to push the filament through the hotend. If there is 0.5-1cm sticking out of the filament, reaching the Bondtech filament-pulley starts with Method number 2, pulling it out with pliers.</p>
<h3>Setup</h3>
<ol>
<li>Go to the <em>LCD Menu -&gt; Settings -&gt; Temperature -&gt; Nozzle</em> and set the temperature to 280º C. Wait for 3-5 minutes with the hotend at this temperature.</li>
<li>In the LCD menu in <em>Settings,</em> select <em>Disable steppers</em>.</li>
<li>Go to the  <em>LCD Menu -&gt; Settings -&gt; F. Autoload,</em> so A<em>utoload</em> will not interfere.</li>
</ol>
<div class="warning-callout">From now on the hotend will be hot! Avoid touching the lower part of the extruder (heaterblock + nozzle)!</div>
<h3>Method 1: Pushing the filament through the hotend</h3>
<p>Using another piece of filament, a thin (1-1,5 mm) Allen-wrench or same diameter wire, at least 4.5 cm long for the MK3(s) and 6 cm long for the MMU2s, you are often able to simply push it through.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0270scales.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0270scales-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0270scales-533x400.jpg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0270scales-768x576.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0270scales-800x600.jpg 800w" alt="" width="574" height="431" loading="lazy" /></p>
<p> </p>
<ol>
<li>Feed in from the top of the extruder your tool of choice, down past the Bondtech-gear, and on top of the stuck filament.</li>
</ol>
<div class="note-callout">If you are able to push the stuck filament down the PTFE-tube with an Allen-wrench, switch to using filament after about 1-2 cm. Some Allen-wrenches may only be long enough to get it started.</div>
<ol start="2">
<li>In case the filament starts being extruded from the bottom, Keep pushing the filament to clear the nozzle and see the color change.</li>
</ol>
<h3>Method 2: Pull out filament with pliers</h3>
<p>While hotend is heated to 280° C, firmly grab the filament with the needle-nose pliers that came with the printer. Slowly drag/feed the filament upwards, bit by bit, through the top of the extruder body, until it is completely removed from the PTFE-tube.</p>
<p>The filament can get stuck on geometry on the path up through where it is fed. It is also possible to pull it out of the idler door.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0275.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0275-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0275-533x400.jpg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0275-768x576.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/DSC_0275-800x600.jpg 800w" alt="" width="627" height="470" loading="lazy" /></p>
<p> </p>
<div class="tip-callout">After removing the filament, do a <a href="http://help.prusa3d.com/article/cold-pull-mk3-s-mk2-5-s-mk3-5-s_2075">Cold pull (MK3/S/+, MK2.5/S, MK3.5/S)</a> to ensure you have fully cleared the clog.</div>
<h3>Nope, it is still stuck</h3>
<p>If none of these methods work, it means that the tip is not touching the part of the hotend that is heated and is stuck in the PTFE-tube. In this case, you must extract the PTFE-tube. Follow the guide linked below to resolve it.</p>
<div class="note-callout">You will probably need to heat the hotend to extract the PTFE-tube with the stuck filament.</div>
<ul>
<li><a href="http://help.prusa3d.com/guide/how-to-replace-a-ptfe-tube-mk3-mk2-5_17360">How to replace a PTFE tube (MK3/MK2.5)</a></li>
<li><a href="http://help.prusa3d.com/guide/how-to-replace-a-hotend-ptfe-tube-mk3s-mk3s-mk2-5s-mmu2s_21664">How to replace a hotend PTFE tube (MK3S+/MK3S/MK2.5S/MMU2S)</a></li>
</ul>


Removing filament from extruder manually

<div class="warning-callout">This guide is for the E3D V6 Hotend on the MK-series. <strong>NOT FOR THE PRUSA MINI!</strong></div>
<p>You can find the complete <a href="https://e3d-online.zendesk.com/hc/en-us/articles/360017013257-V6-Assembly-Guide-Edition-2">E3Ds assembly manual of the V6 hotend</a>, which can be followed backward for disassembly. <strong>This is the stock hotend on an Original Prusa MK3S/MK2.5S/MK2S.</strong> However, as the manual works with brand new parts, it does not consider the changes that happen when being heated repeatedly to hundreds of degrees, again and again. Metal contracts and expands and thermal paste will turn crusty over time. Therefore there are some changes to the procedure when disassembling after a long time of use. </p>
<div class="note-callout">To extract the hotend follow this simple guide for <a href="http://help.prusa3d.com/guide/how-to-replace-a-hotend-ptfe-tube-mk3s-mk3s-mk2-5s-mmu2s_21664">MK3S/MK2,5S/MMU2S</a>, and for <a href="http://help.prusa3d.com/guide/how-to-replace-a-ptfe-tube-mk3-mk2-5_17360">MK3/MK2.5</a>.</div>
<h3>Disassembly</h3>
<p>The <a href="https://e3d-online.zendesk.com/hc/en-us/articles/360017013257-V6-Assembly-Guide-Edition-2">assembly manual for the V6</a> is still optimal for most of this procedure, with a few exceptions. Moving backward, you are first removing the nozzle (at 280 °C) to release the heatbreak. However, this makes it harder to remove the heatbreak from the heat sink in later steps.</p>
<div class="tip-callout">For replacing certain parts of the V6 hotend, like heatsink, heater block, thermistor, etc. you can follow our guide <a href="http://help.prusa3d.com/guide/how-to-replace-a-heatbreak-heaterblock-heatsink-mk3-mk2-5_14944">How to replace a heatbreak/heaterblock/heatsink (MK3/MK2.5)</a>.</div>
<p>As the heatbreak can be quite fragile, and its threads me be damaged if you try to grip it with pliers, <strong>we recommend that you unscrew the heatsink from the heatbreak, before removing the nozzle,</strong> which locks the heatbreak in place. A Heatbreak can still bend and break so do not unscrew it at an angle. A bend will create a whole range of printing issues.</p>
<p>After you have unscrewed the heat sink from the heatbreak, proceed with the E3Ds assembly manual, by heating the block and unscrewing the nozzle.</p>
<h3>Too late, it is already stuck!</h3>
<p>Follow this procedure to resolve the issue.</p>
<ol>
<li>Without any heat, manually screw your nozzle into its threaded hole in the heater block. </li>
<li>Screw it all the way in, then loosen it back a full turn (as described in step 3 of the E3D V6 Hotend assembly) creating a gap of about 1mm between nozzle and block.</li>
<li>Then screw the heatbreak, with the attached heatsink, into the heatblock from the other side as far as it will go.</li>
<li>Tighten the nozzle with a pair of pliers and you now have a better handle. You can also grab this with pliers for some leverage when unscrewing the stuck heatsink.</li>
</ol>


Hotend disassembly & heatbreak stuck in the heatsink

<p>The Bondtech gears have a lot of pulling force. They might seem secure, but unless properly tightened, <strong>on the flat side of the motor's shaft,</strong> they can come loose and remain stationary around the spinning shaft. This might only be intermittent at first, acting like under extrusion, but the gear will continue to loosen and/or slide out of alignment with the filament path.</p>
<h3>Typical issue (false clog)</h3>
<p>This might appear as a clog at first, but you can see the motor axle rotating fully, and there is no clicking sound, which is common during a hotend clog. The filament is not moving at all and when pulled out, it does not look like it has been ground by the gear, hence the name "false or ghost clog".</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/Extrdueer-motor72dpi.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/Extrdueer-motor72dpi-300x265.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/Extrdueer-motor72dpi-453x400.jpg 453w, https://cdn.help.prusa3d.com/wp-content/uploads/Extrdueer-motor72dpi-768x678.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/Extrdueer-motor72dpi-680x600.jpg 680w" alt="" width="451" height="398" loading="lazy" /></p>
<div class="tip-callout" style="text-align: center;">It can be helpful to draw a line on the radius of the axle, to see if it spins or not.</div>
<h3>Accessing the Bondtech gear</h3>
<p>Start by getting out your 1,5 mm and 2.5 mm Allen keys. Using the 2.5 mm Allen key, release the spring-tensioned idler-screw(s) completely and open the idler door. It is 1 on the Original Prusa MK3S &amp; MK3S+ (left picture) and two on the Original Prusa MK3 (right picture). The MMU2S extruder has one screw, but some additional parts.</p>
<table style="border-collapse: collapse; width: 99.7482%; height: 376px;" border="0">
<tbody>
<tr style="height: 454px;">
<td style="width: 33.3333%; height: 358px; vertical-align: bottom;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu-533x400.jpg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu-768x576.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/4aheOXhkPQx2kAAu-800x600.jpg 800w" alt="" width="533" height="400" loading="lazy" /></td>
<td style="width: 33.3333%; height: 358px; vertical-align: bottom;"><em><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/MK3.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/MK3-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/MK3-534x400.jpg 534w" alt="" width="533" height="400" loading="lazy" /></em></td>
</tr>
<tr style="height: 18px;">
<td style="width: 33.3333%; height: 18px; text-align: center;"><em>Original Prusa MK3S &amp; MK3S+ / MK3.5</em></td>
<td style="width: 33.3333%; height: 18px; text-align: center;"><em>Original Prusa MK3 (Non S/+-upgrade)</em></td>
</tr>
</tbody>
</table>
<table style="border-collapse: collapse; width: 100%; height: 436px;" border="0">
<tbody>
<tr style="height: 400px;">
<td style="width: 100%; text-align: center; height: 400px;"><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/idlermmu2s.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/idlermmu2s-300x225.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/idlermmu2s-533x400.jpg 533w, https://cdn.help.prusa3d.com/wp-content/uploads/idlermmu2s-768x576.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/idlermmu2s-800x600.jpg 800w" alt="" width="533" height="400" loading="lazy" /></td>
</tr>
<tr style="height: 36px;">
<td style="width: 100%; height: 36px;">
<p> <strong>On the Original Prusa MMU2S / MMU3, you must remove the whole idler door (<span style="color: #3598db;">blue arrows</span>), by removing</strong></p>
<p style="text-align: center;"><strong>the screw acting as its hinge (<span style="color: #e03e2d;">red arrow</span>).</strong></p>
</td>
</tr>
</tbody>
</table>
<div class="tip-callout">On the Original Prusa MK3S, <a href="http://help.prusa3d.com/guide/5-e-axis-assembly_28536#30456">remove the single screw on the top of the extruder</a> to remove the fil. sensor cover to open the idler door all the way.</div>
<h3>Rotating the motor's shaft</h3>
<p>You will now have access to the Bondtech gears. With the idler door open, we will check if the Bondtech gear is secured on the <strong>flat side of the motor shaft and if the gear is out of alignment with the filament path.</strong> We do not recommend moving the motor shaft by hand. The best is to start rotation from the LCD menu:</p>
<ul>
<li>Preheat the nozzle from the <em>LCD-menu -&gt; Setting -&gt; Temperatures -&gt; Nozzle -&gt; 180 °C.</em> The firmware will not let you manually move the extruder motor unless heated to at least 175 °C.</li>
</ul>
<div class="warning-callout"><strong>The nozzle is now hot!</strong> Be careful so you do not burn yourself.</div>
<ul>
<li>Navigate the LCD menu to <em>Settings -&gt; Move axis -&gt; Extruder</em>, and you can now spin the extruder motor, with the knob on the LCD panel. </li>
</ul>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign-300x290.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign-413x400.jpg 413w, https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign-768x743.jpg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/bondtechallign-620x600.jpg 620w" alt="" width="465" height="450" loading="lazy" /></p>
<p>Make sure the flat side of the motor shaft is visible (<span style="color: #e03e2d;"><strong>red lines</strong></span>), aligned with the black set-screw on the pulley (<span style="color: #b96ad9;"><strong>purple arrow</strong></span>), and that pulley grooves are aligned with the filament (<span style="color: #2dc26b;"><strong>green line</strong></span>).</p>
<div class="warning-callout">The set-screw may be stuck due to rust or Loctite. If you have to use a lot of force you may risk stripping the head of the screw. Consult with our <a href="http://help.prusa3d.com/article/customer-support_2287">technical support</a> before you use excessive force.</div>
<p>You can use a piece of filament, inserted from the top (<span style="color: #3598db;"><strong>blue arrow</strong>)</span>, to check alignment. Then use the 1.5 mm Allen wrench or your nail to move the Bondtech gear into position, before securing the set screw.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/aa928d37bf9ddb9e_painted.jpeg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/aa928d37bf9ddb9e_painted-400x400.jpeg 400w, https://cdn.help.prusa3d.com/wp-content/uploads/aa928d37bf9ddb9e_painted-600x600.jpeg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/aa928d37bf9ddb9e_painted-300x300.jpeg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/aa928d37bf9ddb9e_painted-768x768.jpeg 768w, https://cdn.help.prusa3d.com/wp-content/uploads/aa928d37bf9ddb9e_painted-1536x1536.jpeg 1536w" alt="" width="450" height="450" loading="lazy" /></p>
<h3>Clean Bondtech gear</h3>
<p>Open the Extruder idler. You can see how to do it in our assembly manuals, section <a href="http://help.prusa3d.com/guide/5-e-axis-assembly_28536#29848">Extruder idler parts preparation</a>, in the E-axis assembly chapter. Clear any left-over filament, rust, or dust with a brush and inspect both gears.</p>
<p>It is recommended to use a <a href="https://www.prusa3d.com/product/prusa-lubricant-applicator-set-5g/">Prusa Lubricant</a> or a PTFE-based grease. However, be careful not to overuse it, as it tends to accumulate dust particles over time. This procedure should be done roughly every 3-6 months, depending on how often you are using 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/2022/10/cleaning-Bondtech-gear.jpg" alt="" width="600" height="267" loading="lazy" /></p>
<p>Put the lubricant on the Bondtech extruder gear teeth. <strong>Apply it only to the toothed part</strong> as seen in the right photo above. If you apply it to the whole gear, it will be unable to grab filament properly!</p>
<p>You can also inspect the needle bearings that are inside and clean them with a brush. However, these do not need any special care, just make sure that both of them are properly inserted.</p>
<p><img decoding="async" style="display: block; margin-left: auto; margin-right: auto;" src="https://cdn.help.prusa3d.com/wp-content/uploads/2022/10/Bondtech-need-bearings.jpg" alt="" width="400" height="174" loading="lazy" /></p>

Checking/re-aligning the Bondtech gear (MK3.5/S, MK3S/+, MK2.5S)

<p>Our brand new <strong>Original Prusa i3 MK3&nbsp;</strong>comes with lots of new safety features. That makes printing a lot more reliable and safe. In this article, we will showcase how to properly test all of them and how to debug them.</p>
<p>All of these features must be tested&nbsp;<strong>during a running print.&nbsp;</strong> You can use models from the bundled SD card, for instance, the&nbsp;<strong>Batman&nbsp;</strong>or<strong>&nbsp;Prusa logo.</strong></p>
<h3>Filament sensor&nbsp;</h3>
<h4>How to test the filament sensor</h4>
<p style="text-align: center;"><iframe loading="lazy" src="https://www.youtube.com/embed/KDJq0WplXb0" width="560" height="315" frameborder="0" allowfullscreen="allowfullscreen"></iframe></p>
<ol>
<li>First, you must make sure that the Filament sensor is turned on. You can check that in the&nbsp;<strong>LCD Menu - Settings - Fil. sensor ON/OFF.</strong></li>
<li>Let the print run for 5-10 minutes, then simply <strong>cut the filament</strong>&nbsp;and wait until the sensor triggers it.</li>
<li>The printer will then ask you to&nbsp;<strong>press the knob&nbsp;</strong>and unload the filament.</li>
<li>After that, simply load a new filament into the extruder. Either by <strong>pressing the knob&nbsp;</strong>or if you have the autoload turned on, it will be done automatically.&nbsp;</li>
<li>If changed correctly. Select <strong>YES</strong>. If you did not load the filament, select <strong>Filament not load</strong> or if the color is not clear select <strong>Color not clear.</strong></li>
</ol>
<h4>False sensor reading and debugging&nbsp;</h4>
<ol>
<li>Check if the sensor is positioned correctly and <strong>connectors are properly seated.</strong></li>
<li>Make sure that there is no&nbsp;<strong>dust on the sensor&nbsp;</strong>or&nbsp;<strong>extreme light conditions.</strong></li>
<li>For more information, see <a href="http://help.prusa3d.com/article/ir-filament-sensor-mk2-5s-mk3s-mk3-5-s_112214">IR Filament Sensor (MK2.5S, MK3S/+, MK3.5/S)</a>.</li>
</ol>
<h3>Skipped steps and layer detection&nbsp;</h3>
<p style="text-align: center;"><iframe loading="lazy" src="https://www.youtube.com/embed/KDJq0WplXb0?start=145" width="560" height="315" frameborder="0" allowfullscreen="allowfullscreen"></iframe></p>
<h4>How to test the "crash" detection&nbsp;</h4>
<ol>
<li>Make sure that your printer is running in the&nbsp;<strong>normal mode.</strong> You can check that in&nbsp;<strong>LCD - Settings - Mode Normal/Stealth</strong>&nbsp;and that the crash detection is enabled in<strong>&nbsp;LCD - Settings - Crash</strong> det<strong>. ON/OFF.</strong></li>
<li><strong>Pinch</strong> the smooth rods close to the extruder, which will result in stopping it while printing.</li>
<li><strong>Do not&nbsp;</strong>push the extruder. As this does not simulate a real printing scenario.</li>
<li>If done properly, the extruder will&nbsp;<strong>auto home&nbsp;</strong>and restore printing automatically.&nbsp;</li>
</ol>
<h4>The printer is not recognizing hits and skips&nbsp;</h4>
<ol>
<li>Double-check that you are running the printer in the normal mode.&nbsp;</li>
<li>Make sure that your belt and pulley are tightened. Would any of them be loose, it may cause the belt to&nbsp;<strong>jump&nbsp;</strong>over the pulley or the pulley to&nbsp;<strong>spin&nbsp;</strong>around the motor shaft.&nbsp;</li>
<li>If the crash detection does not work, you can visit <a href="http://help.prusa3d.com/article/layer-shifting_2020">Layer shifting</a> for more information. (Layer shifting has a lot in common with none working crash detection.)&nbsp;</li>
</ol>
<h3>Power panic</h3>
<p style="text-align: center;"><iframe loading="lazy" src="https://www.youtube.com/embed/KDJq0WplXb0?start=82" width="560" height="315" frameborder="0" allowfullscreen="allowfullscreen"></iframe></p>
<h4>How to test power panic</h4>
<ol>
<li>Do not use the&nbsp;<strong>power switch.&nbsp;</strong>That does not trigger power panic.</li>
<li>You can pull the power cord from the wall. However, it may not work all the time.&nbsp;<strong>Best practice</strong> is to have a <strong>power strip</strong> with an ON/OFF switch.&nbsp;</li>
<li>So simply <strong>switch off&nbsp;</strong>the power strip in the middle of your print.&nbsp;</li>
<li>The printer will then raise the nozzle and once the power is back, it will heat up and restore printing without user interaction.&nbsp;</li>
<li><span data-hd-color="rgb(192, 80, 77)"><strong>If the power goes off for a longer period of time and the nozzle/bed is cool. The printer will wait for you and ask if you want to restore printing.&nbsp;</strong></span></li>
</ol>
<h4>Power panic did not trigger or work&nbsp;</h4>
<ol>
<li>If it did not trigger while <strong>unplugging</strong>&nbsp;the power cord (which we do not recommend). It may have been caused by <strong>arcing</strong> produced by the cord.</li>
<li><strong>Nozzle did not rise far enough.&nbsp;</strong>
<ol>
<li>Make sure that you are running&nbsp;<strong>the newest&nbsp;</strong>firmware version. The actual firmware version running on your printer can be found in the<strong>&nbsp;LCD menu under <em>Support -&gt; Firmware</em>.&nbsp;</strong>The latest version can be always found at our <a href="https://help.prusa3d.com/en/downloads/">Downloads page</a>.</li>
<li>Check your Z-axis assembly. Any extra friction might prevent the proper Z movement.</li>
</ol>
</li>
</ol>


Testing safety features (MK3/MK3S)

<p>If you are trying to unscrew any of the screws in the printer, and the key keeps turning without releasing the screw, it means that the screw is stripped.</p>
<p>You might wish to drill the screw and using an extractor if you have experience using these tools. If you do not have experience, do not attempt it, and follow the tips below.</p>
<div class="warning-callout">Do not follow internet tutorials if they are not specific for electronics or sensitive parts. Methods specific for woodworking might damage your printer.</div>
<div class="tip-callout">If you have a strong magnet, you can attach it to your Allen key to remove any possible debris and help with the screw extraction.</div>
<ol>
<li>Different Allen key: you might be using an incorrect Allen key, or the tool might be damaged. Try using the other side of the Allen key. This can happen especially for the smaller screws.</li>
<li>Better grip of the screw: if the head of the screw is damaged, you can place something between the head of the screw and the Allen key to make the grip better. The most commonly used material are wide rubber bands, but others things can be used: latex gloves, aluminum foil, steel wool. Make constant pressure towards the screw, and <strong>slowly</strong> turn the key until the screw is out.</li>
<li>Pliers: if you can see the head of the screw, try to firmly hold the head of the screw with pliers, and rotate the pliers until the screw is loose.</li>
</ol>
<div class="tip-callout">After removing the damaged screw please throw it away to make sure you will not use it again.</div>


How to remove a stripped screw

<p>Before you start printing, you should know that various materials have different adhesions on various surfaces. It is crucial to pick the right steel sheet for your printer and prepare its surface properly. This article is about the most common types of print surfaces and how to prepare them for printing.</p>
<div class="tip-callout">To kick it off with a quick (and most common) example: PETG filament has great adhesion to a clean, degreased, smooth PEI sheet, making it extremely hard to remove. Removing the print often leads to peeling off the PEI surface and irreversible damage to the sheet. This is why we recommend using another type of steel sheet or adding PVA glue as a separation layer on the print surface.</div>
<h3><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/steelsheet.jpg" alt="" width="1024" height="703" loading="lazy" /></h3>
<p><em>Steel sheet damaged by a PETG print</em></p>
<h3>Choosing the right print sheet</h3>
<p>We offer 4 types of spring steel sheets, each has a different surface finish that leaves not only a specific texture on your print but also supports a variety of materials that can be printed on it.</p>
<div class="note-callout"><a href="http://help.prusa3d.com/article/smooth-steel-sheet_196550">Here’s a guidepost</a> that provides the most information about the maintenance and properties of our three most common print sheets. Plus, <a href="http://help.prusa3d.com/article/special-pa-nylon-steel-sheet_341570">here’s an article</a> about our special PA Nylon steel sheet.</div>
<table style="border-collapse: collapse; width: 100%; height: 36px; margin-left: auto; margin-right: auto;" border="0">
<tbody>
<tr style="height: 18px;">
<td style="width: 32.2013%; height: 18px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/spring-steel-sheet-smooth-peiKB.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/spring-steel-sheet-smooth-peiKB-400x400.jpg 400w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/spring-steel-sheet-smooth-peiKB-600x600.jpg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/spring-steel-sheet-smooth-peiKB-300x300.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/spring-steel-sheet-smooth-peiKB-768x768.jpg 768w" alt="" width="266" height="266" loading="lazy" /></td>
<td style="width: 32.2013%; height: 18px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/powder-coated-spring-steel-sheetKB.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/powder-coated-spring-steel-sheetKB-400x400.jpg 400w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/powder-coated-spring-steel-sheetKB-600x600.jpg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/powder-coated-spring-steel-sheetKB-300x300.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/powder-coated-spring-steel-sheetKB-768x768.jpg 768w" alt="" width="266" height="266" loading="lazy" /></td>
<td style="width: 32.2013%; height: 18px;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/double-sided-powder-coated-satin-spring-steel-sheetKB.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/double-sided-powder-coated-satin-spring-steel-sheetKB-400x400.jpg 400w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/double-sided-powder-coated-satin-spring-steel-sheetKB-600x600.jpg 600w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/double-sided-powder-coated-satin-spring-steel-sheetKB-300x300.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2020/12/double-sided-powder-coated-satin-spring-steel-sheetKB-768x768.jpg 768w" alt="" width="266" height="266" loading="lazy" /></td>
</tr>
<tr style="height: 18px;">
<td style="width: 32.2013%; height: 18px; text-align: center;"><a href="http://help.prusa3d.com/article/smooth-steel-sheet_196550">Smooth sheet</a></td>
<td style="width: 32.2013%; height: 18px; text-align: center;"><a href="http://help.prusa3d.com/article/textured-steel-sheet_196534">Textured sheet</a></td>
<td style="width: 32.2013%; height: 18px; text-align: center;"><a href="http://help.prusa3d.com/article/satin-steel-sheet_196526">Satin sheet</a></td>
</tr>
<tr>
<td style="width: 32.2013%; text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/Smooth_underside2.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/Smooth_underside2-398x400.jpg 398w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/Smooth_underside2-598x600.jpg 598w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/Smooth_underside2-300x300.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/Smooth_underside2-768x771.jpg 768w" alt="" width="266" height="267" loading="lazy" /></td>
<td style="width: 32.2013%; text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/TXT_underside2.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/TXT_underside2-398x400.jpg 398w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/TXT_underside2-598x600.jpg 598w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/TXT_underside2-300x300.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/TXT_underside2-768x771.jpg 768w" alt="" width="266" height="267" loading="lazy" /></td>
<td style="width: 32.2013%; text-align: center;"><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/satin_underside2.jpg" sizes="100vw" srcset="https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/satin_underside2-398x400.jpg 398w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/satin_underside2-598x600.jpg 598w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/satin_underside2-300x300.jpg 300w, https://cdn.help.prusa3d.com/wp-content/uploads/2021/01/satin_underside2-768x771.jpg 768w" alt="" width="266" height="267" loading="lazy" /></td>
</tr>
</tbody>
</table>
<p>The best way to identify whether your sheet is suitable for the chosen material is by <a href="https://help.prusa3d.com/en/materials"><strong>checking our Material table</strong></a>. If there’s a green check mark matching the selected sheet and material, you can simply degrease the print surface and you’re good to go. If there’s an exclamation mark, a separation layer of some sort is needed (see below). <strong>Failing to use the separation layer may lead to damaging your sheet!</strong></p>
<p><img decoding="async" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/04/cbf6b670e81a869ca569857434eba048.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Print surface preparation" alt="" width="1950" height="656" loading="lazy" /></p>
<h3>Cleaning the print surface</h3>
<p>This is an easy, yet crucial step you should perform before (almost) every print. We already described this in the <a href="https://www.prusa3d.com/downloads/manual/prusa3d_manual_MK4_MK39_103_en.pdf">3D printing handbook</a> and several other places but here’s a quick reminder:</p>
<p>Grease stains (fingerprints, etc.) often cause poor surface adhesion and, eventually, a print failure. To degrease the print sheet, <strong>spray some isopropyl alcohol (90% or stronger)</strong> or denatured ethyl alcohol <strong>on the cold print surface</strong> and wipe it with an unscented paper towel. Do not use any products for skin care: they usually contain oils that ruin adhesion!</p>
<div class="note-callout">There are some more specific rules for long-term sheet maintenance and you should definitely learn these but it reaches beyond this article’s purpose. Don’t forget to go through <a href="http://help.prusa3d.com/article/smooth-steel-sheet_196550">the steel sheet guidepost</a>. Keep in mind that the <a href="http://help.prusa3d.com/article/special-pa-nylon-steel-sheet_341570">special PA Nylon sheet</a> has very different and highly specific rules for maintenance.</div>
<p>Alright, the print surface is clean, now the final checklist (<a href="https://help.prusa3d.com/en/materials">see the material table</a>):</p>
<ol>
<li><strong>Green check mark:</strong> Good to go!</li>
<li><strong>Yellow exclamation mark:</strong> Use a separation layer (see below).</li>
<li><strong>Red X:</strong> Do not print! The chosen material may damage your print sheet!</li>
</ol>
<h3>Using the most common separation layers</h3>
<p>You may find various separation (or adhesive) layer materials on the market, some of those even in our e-shop. Every material has its benefits, but describing every single one of them is beyond the scope of this article. If you check our material table, you’ll find out that it all comes down to two most common separation layers: <strong>PVA glue stick and PP tape.</strong></p>
<p><strong>PVA (paper) glue</strong> is usually sold in the form of sticks that make the application easier. <strong>Usually, only a thin layer of glue is enough.</strong> Spreading a thick layer may leave various unsightly traces, bumps, and artifacts that will be imprinted onto your 3D print’s surface. However, if you want to print a mechanical part, where good looks are not as important as functionality and reliability, making the layer slightly thicker won’t hurt. Also, the PVA glue melts at relatively low temperatures, so we suggest applying it on a cold surface to avoid making an extra thick layer.</p>
<div class="tip-callout">Tip: If you use the smooth print sheet, use the grid to guess the print size and position, then spread the glue only under the 3D print. You don’t need to spread the glue all over the whole sheet.</div>
<table style="border-collapse: collapse; width: 100%;" border="1">
<tbody>
<tr>
<td style="width: 32.2431%;"><img decoding="async" loading="lazy" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/04/d1bc8e9178fa20c7820b6c520c3777e0.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Print surface preparation" alt="" width="2506" height="1880" /></td>
<td style="width: 32.2431%;"><img decoding="async" loading="lazy" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/04/bb07c0b1d669e31b19f99420c5445ec0.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Print surface preparation" alt="" width="2506" height="1879" /></td>
<td style="width: 32.2457%;"><img decoding="async" loading="lazy" src="https://cdn.help.prusa3d.com/wp-content/uploads/2024/04/188aee6aea6ea114ef0b3a710169a3d1.jpg" sizes="(min-width: 1024px) 820px, 100vw" srcset="Print surface preparation" alt="" width="2506" height="1879" /></td>
</tr>
</tbody>
</table>
<p><em>PVA glue separation layer, 3D printed PETG parts, and marks left after removing the print. Note that these marks are normal as they are only on a PVA glue layer and not on the print sheet surface. These marks disappear with the glue after washing.</em></p>
<p>Finally, <strong>the PP tape.</strong> You will most likely not use it, since it’s recommended only for printing PP (Polypropylene), which is quite rare material to print. However, you may decide to use some other tape - kapton tape, for example. For the best adhesion, it is recommended to use in combination with a smooth sheet, no matter which tape you are going to choose. The tape may leave some glue residuals after removing it from the print sheet surface. Usually, these can be washed with IPA or with water and dishwasher soap, but again, double-check the <a href="http://help.prusa3d.com/article/smooth-steel-sheet_196550">steel sheet maintenance articles</a> before washing them.</p>
<div class="warning-callout">If you decide to use other separation materials or adhesives, don’t forget to check compatibility with our print sheets. For example, ABS juice should not be used in combination with textured or satin sheets.</div>
<h3>Removing the print</h3>
<p>One last thing: <strong>always remove the prints by removing and bending the sheet only after they are cooled down.</strong> The print will go off easily without the necessity of using various spatulas, knives, or anything else.</p>


Print surface preparation

How to replace a hotend PTFE tube (MK3S+/MK3S/MK2.5S/MMU2S)

<p>The firmware for each Original Prusa printer is currently translated into multiple languages and we would like to expand it further. We welcome everyone to join us and localize the printer to their native language. Translation process was designed to be easy. However, there are certain requirements regarding your IT skills, but we believe that everyone can join. In case you run into some issues, we will be there to help.</p>
<p>In case you would like to translate and maintain the translations, contact us by filling the form below. Before you sign in, please note that this is not a one-time translation job. Our developers are constantly improving the firmware and adding new features. This requires you to be in touch with us and keep your language up to date. Also, check whether the selected language isn't already being maintained by somebody else, our aim is to have <strong>two maintainers per language</strong>.</p>
<p><a href="https://forms.gle/TAwtshinUdKP58jn6">Prusa Translation Program Form</a></p>
<p>Once we process your request and prepare certain things, we will get back to you with further instructions.</p>
<p><em>Note: Original Prusa printers come with different hardware (e.g. MK3S+ vs MINI+) and there might be certain limits regarding the languages, which can or can not be translated. Specifically, some screens might have issues with displaying certain characters. If your language is not listed below, we are currently unable to display it.</em></p>
<h3>List of the printers and supported languages</h3>
<table class="striped" style="width: 99.9654%; height: 478.75px;">
<tbody>
<tr style="height: 18.75px;">
<td style="width: 99.9562%; height: 18.75px;" colspan="2"><strong>MK3/MK3S/MK3S+</strong></td>
</tr>
<tr style="height: 18.75px;">
<th style="width: 47.8438%; height: 18.75px;"><strong>Language</strong></th>
<th style="width: 52.1124%; height: 18.75px;"><strong>Maintainer</strong></th>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">English</td>
<td style="width: 52.1124%; height: 18.75px;">Prusa Research</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">German</td>
<td style="width: 52.1124%; height: 18.75px;">Prusa Research</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Czech</td>
<td style="width: 52.1124%; height: 18.75px;">Prusa Research</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">French</td>
<td style="width: 52.1124%; height: 18.75px;">Prusa Research</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Spanish</td>
<td style="width: 52.1124%; height: 18.75px;">Prusa Research</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Italian</td>
<td style="width: 52.1124%; height: 18.75px;">Prusa Research</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Polish</td>
<td style="width: 52.1124%; height: 18.75px;">Prusa Research</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Dutch</td>
<td style="width: 52.1124%; height: 18.75px;">@3d-gussner &amp; @vintagepc</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Swedish</td>
<td style="width: 52.1124%; height: 18.75px;">@Painkiller56 &amp; @pkg2000<em><br /></em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Danish</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Slovak</td>
<td style="width: 52.1124%; height: 18.75px;">@ingbrzy &amp; @shatter136</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Finnish</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Romanian</td>
<td style="width: 52.1124%; height: 18.75px;">@Hauzman &amp; @leptun</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Portuguese</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Hungarian</td>
<td style="width: 52.1124%; height: 18.75px;">@AttilaSVK &amp; @Hauzman</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Croatian</td>
<td style="width: 52.1124%; height: 18.75px;">@Prime1910 &amp; @PRPA041</td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Estonian</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Latvian</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Luxembourgish</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Bahasa Malaysia (Latin alphabet)</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Turkish</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Slovenian</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 18.75px;">
<td style="width: 47.8438%; height: 18.75px;">Icelandic</td>
<td style="width: 52.1124%; height: 18.75px;"><em>open</em></td>
</tr>
<tr style="height: 10px;">
<td style="width: 47.8438%; height: 10px;">Norwegian</td>
<td style="width: 52.1124%; height: 10px;">@pkg2000 &amp; @trondkla</td>
</tr>
</tbody>
</table>
<p><em>Other printers like SL1S, SL1, MINI+, MINI and others are coming soon.&nbsp;</em></p>
<p>&nbsp;</p>
<h3>Suggestions to the existing translation</h3>
<p>Should you have any suggestion to the translation, please contact fill in this <a href="https://github.com/prusa3d/Prusa-Firmware/issues/new?assignees=&amp;labels=community_made&amp;template=community.md&amp;title=%5BCommunity+made%5D+%3CEnter+comprehensive+title%3E" target="_blank" rel="noopener noreferrer">GitHub issue</a>.</p>


Community translations

How to replace a heatbreak/heatsink/heaterblock (MK3S+/MK3S/MK2.5S/MMU2S)

How to replace a heatbed thermistor (MK3S+/MK3S/MK2.5S/MK2S)

Replacing the PEI sheet on the (MK3S/MK3/MK2.5S/MK2.5)

How to replace a hotend thermistor (MK3S/MK3S+)

How to replace an IR-sensor (MK3S/MK3S+)

How to replace PSU on MK3 printers

<p><strong>This is a major release, please, update!</strong>Stats: 409 commits, 108 pull requests, 66 closed issues, cooperation with 14 developers</p>
<ul>
<li>Linear Advance 1.5</li>
<li>Automatic E-jerk conversion</li>
<li>Screen brightness adjustment</li>
<li>Filament sensor recognition</li>
<li>New G-code files sorting</li>
<li>Toggle and Translations</li>
<li>Show current Z offset in reset dialog before first layer calibration</li>
<li>Unknown Z coordinate displayed</li>
<li>Safer moves in Z-axis, if the position is unknown</li>
<li>Heating disabled during MBL</li>
<li>MINTEMP value lowered</li>
<li>MINTEMP error differentiated</li>
<li>Flickering “Statistics” screen fixed</li>
<li>Tone timer re-enabled</li>
<li>Nozzle crash protection improved</li>
<li>Belt test improvements</li>
<li>Decoupling XYZ relative and E relative</li>
</ul>


3.9.0

<ul>
<li>Major improvements to LA15</li>
<li>Support for parts from selected vendors</li>
<li>Ambient temperature check</li>
<li>PC Blend preheat added</li>
<li>Stack corruption fixed</li>
<li>More precise Belt test</li>
<li>Octoprint causing M112 fixed</li>
</ul>


3.9.1

<ul>
<li>XYZ calibration optimization - SuperPINDA compatibility (<a href="https://blog.prusaprinters.org/november2020_update_original_prusa_i3_mk3splus_miniplus_mini_kit_satin_steel_sheet_40870/" target="_blank" rel="noopener noreferrer">more info</a>)</li>
</ul>


3.9.2

<ul>
<li>Changes related to MK3S+ release</li>
<li>Linear advance 1.5 chapter updated</li>
<li>Dozens of small changes</li>
</ul>


3.15

<ul>
<li>Redesigned XYZ calibration, which is now more precise</li>
</ul>


3.9.3

<ul>
<li>New "Print from SD" menu</li>
<li>"Time Remaining" function improved</li>
<li>Community translations</li>
<li>Faster and quieter XYZ calibration</li>
<li>PVB preheat preset</li>
<li>Satin sheet profiles</li>
<li>G-code "M204 T" implemented</li>
<li>Improved filament troubleshooting</li>
<li>Support for 0.8mm nozzles</li>
<li>Optimizations for print hosts (e.g. Octoprint)</li>
<li>Optimized code size and RAM usage</li>
<li>File listing adjusted for remote printing software</li>
<li>Z offset during M600 reverted</li>
<li>Factory reset menu extended</li>
</ul>


3.10.0

<ul>
<li>PrusaSlicer 2.3.3
<ul>
<li>Patch release - fixing the bug in handling FDM multi-material project and configuration files</li>
</ul>
</li>
</ul>


2.3.3

<ul>
<li>Steel sheets chapters updated with the info about Satin sheets</li>
<li>The separate chapter about Satin sheets added</li>
<li>Chapter Printer unpacking and proper handling updated</li>
<li>Chapter LCD Menu updated according to the latest firmware</li>
<li>Language Settings chapter updated</li>
<li>Dump memory chapter added</li>
<li>Info about 0.8mm nozzle added</li>
<li>Small updated in Materials chapters</li>
</ul>


3.16

<ul>
<li>New debugging functions &amp; crash analysis tools</li>
<li>A rare memory bug debugged and fixed</li>
<li>Long-Press action fixed</li>
<li>Move auto reporting out of the temperature ISR</li>
<li>Uint8_t used consistently for the block buffer's index</li>
<li>Arduino boards definition updated</li>
<li>Build script updated</li>
<li>Algorithm for reading SN in EEPROM improved</li>
<li>Spanish translation fixed</li>
<li>Firmware version parsing removed</li>
<li>Bug fixes</li>
</ul>


3.10.1

<ul>
<li>Multi-material painting</li>
<li>Improved supports and bridging</li>
<li>Shape gallery</li>
<li>Fuzzy skin</li>
<li>Windows dark mode</li>
<li>Brim for individual objects</li>
<li>Negative volumes</li>
<li>Automatic color change for logos and signs</li>
<li>Tip of the day notifications</li>
<li>Model simplification</li>
<li>Support for 3DLabPrint airplane models</li>
<li>New 3rd party printer profiles</li>
<li>…and more!</li>
</ul>


2.4.0

<ul>
<li>G-Code Substitutions</li>
<li>Added profiles for Anycubic 4Max Pro 2.0</li>
<li>Added Artillery Hornet profile</li>
<li>Added RatRig V-Core and V-Minion bundle</li>
<li>Added Jubilee bundle</li>
</ul>


2.4.1

<ul>
<li>New community translations</li>
<li>Added LCD support for <code>äöüß</code> and <code>μ</code></li>
<li>SN check fixed</li>
<li>Changes to on-screen messages</li>
<li>Known issue (LCD glitches)</li>
</ul>
<p></p>

3.11.0

<ul class="p-rich_text_list p-rich_text_list__bullet" data-stringify-type="unordered-list" data-indent="0" data-border="0">
<li data-stringify-indent="0" data-stringify-border="0">Updated translations</li>
<li data-stringify-indent="0" data-stringify-border="0">Added profiles for Snapmaker printers</li>
<li data-stringify-indent="0" data-stringify-border="0">Added profiles for Zonestar printers</li>
<li data-stringify-indent="0" data-stringify-border="0">Bug fixes</li>
</ul>
<p></p>

2.4.2

<ul>
<li>Several small changes</li>
</ul>
<p></p>

3.18

<ul>
<li>New perimeter generator Arachne</li>
<li>STEP file format support</li>
<li>Lightning infill</li>
<li>Improved seam placement based on the visibility</li>
<li>Pressure equalizer</li>
<li>New printer and material profiles</li>
<li>Many bugfixes and smaller improvements</li>
<li>Offline unattended installation for mass deploys (in Drivers &amp; Apps package installator).</li>
</ul>
<p></p>

2.5.0

<ul>
<li><span style="font-weight: 400;">New thermal model protection</span></li>
<li>Nozzle change menu</li>
<li>NylonPA sheet profile added</li>
<li>Arc interpolation features G2/G3</li>
<li>UI improvements and fixes</li>
<li>Bug fixes</li>
</ul>
<p></p>

3.12.0


<ul>
<li>Thermal model - important info</li>



<li>Restore correct RPM for fans</li>



<li>Set the calibration state when running M310 A</li>



<li>Max Z-coordinate during Nozzle Change</li>



<li>Message selection fix</li>



<li>Known issues</li>
</ul>


3.12.1


<ul>
<li>Thermal model updates</li>



<li>Update on E3D Revo</li>



<li>Self Test message fixed</li>



<li>FLC procedure updated</li>



<li>List of pull requests</li>
</ul>


3.12.2


<ul>
<li>Improved 'Monotonic lines' fill pattern</li>



<li>Improved Acceleration control</li>



<li>Specific object arrangement for XL</li>



<li>Original Prusa XL profiles</li>



<li>Updated translations</li>



<li>Bugfixes</li>
</ul>


2.5.1


<ul>
<li>Original Prusa MK4 profiles</li>
</ul>


2.5.2


<ul>
<li>Organic supports</li>



<li>Automatic support painter</li>



<li>Text embossing tool</li>



<li>Improved cut tool</li>



<li>Adding connectors and dowel pins</li>



<li>Measurement tool</li>



<li>Dynamic overhang speed</li>



<li>Improved Ensure vertical shell thickness</li>



<li>Smart extending of sparse infill</li>
</ul>


2.6.0


<ul>
<li>Features by the Prusa community
<ul>
<li>E3D Revo support</li>



<li>Meatpack support</li>



<li>Do not preheat the heatbed on load/unload</li>



<li>Features and translations</li>
</ul>
</li>



<li>Support for G-Code M850</li>



<li>First Layer Calibration - nozzle diameter</li>



<li>PrusaLink improvements</li>



<li>Build environment with cmake</li>



<li>Known issues</li>
</ul>


3.13.0


<ul>
<li>XYZ calibration fixed</li>
</ul>


3.13.1


<ul>
<li>New Arrange tool options</li>



<li>New Cut tool options</li>



<li>Per-symbol text projection on surface</li>



<li>Interlocking of painted areas for MMU printing</li>
</ul>


2.6.1


<ul>
<li>New SVG support</li>



<li>Binary G-Code (.bgcode) export support + conversion</li>



<li>Arc fitting support </li>
</ul>


2.7.0


<ul>
<li>Binary G-code settings</li>



<li>Wipe tower weight</li>



<li>Bug fixes</li>
</ul>


2.7.1


<ul>
<li>Smarter color painting</li>



<li>Improved Color change</li>



<li>Ramping travel moves</li>



<li>SLA material overrides</li>
</ul>


2.7.2


<ul>
<li>Fixed Ghost layer shifts</li>



<li>Improved XYZ calibration</li>
</ul>


3.13.3


<ul>
<li>Improvements to multi-material printing</li>



<li>Vase mode smoothing</li>



<li>Support for 3MF files generated in BambuStudio</li>



<li>Metadata with boundary polygon of each object</li>
</ul>


2.7.3


<ul>
<li>Objects from 3MFs generated by BambuStudio now retain multimaterial painting when loaded</li>



<li>Fixed a bug where downloading files from Printables did not work when enabled in Preferences</li>
</ul>


2.7.4


<ul>
<li>Prusa Connect integration</li>



<li>Prusa Account integration</li>



<li>Improved UI</li>



<li>Improved G-code Viewer</li>



<li>New system profile updating system</li>



<li>Single Perimeter for top and bottom layers</li>



<li>Extended SLA layer separation configuration</li>



<li>Bug fixes</li>
</ul>


2.8.0


<ul>
<li>PrusaLink and Prusa Connect updates</li>



<li>PowerPanic improvements</li>



<li>Mesh Bed Leveling (MBL) improvements</li>



<li>New / Improved G-codes</li>



<li>User Interface updates</li>



<li>Community features</li>



<li>Firmware development changes</li>
</ul>


3.14.0


<ul>
<li>Improved menu bar, the menu no longer hides under a button</li>



<li>Two new parameters (Abrasive material and High flow nozzle) for G-Code checks</li>



<li>Improved automatic orientation of bridges</li>



<li>Number of bugfixes</li>
</ul>


2.8.1


<ul>
<li>Add filament presence check at start of print</li>



<li>Region Mesh Bed Levelling fixes</li>



<li>Show filament color/name during M600</li>



<li>Fix safety timer not handled correctly</li>



<li>Delay Z-Axis on Autoload</li>



<li>Replace hard coded crash z lift value with Pause Z lift value.</li>



<li>Send host actions on filament runout</li>



<li>Lower MIN_Z_FOR_UNLOAD from 50mm to 20mm</li>



<li>Add "load filament" if autoload is disabled</li>



<li>Abort nozzle change if filament is loaded</li>



<li>PowerPanic related changes</li>



<li>Reduce ambient shutdown to 80 °C</li>



<li>Added <code>utils/build.py</code> to be able to compile the firmware</li>



<li>MMU related changes</li>



<li>Minor fixes</li>



<li>Community related changes</li>
</ul>


Original Prusa i3 MK3S+

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