filament runout sensor for Prusa mk2s printer

prusaprinters

<p>This is a very simple filament runout sensor to be added to your Prusa mk2s.</p><p> </p><figure class="media"><oembed url="https://www.youtube.com/watch?v=Ss9GOlhPqW8"></oembed></figure><p> </p><p>I have choosen, for reliability reasons to use an endstop switch instead of an optical sensor.<br/>They are very cheap, easy to find on aliexpress<br/><a href="https://s.click.aliexpress.com/e/_9AZ9pU">https://s.click.aliexpress.com/e/\_9AZ9pU</a></p><p>I use the Normally Open switch so that the contact is closed when the filament is inserted.</p><p>Prusa firmware is easily modified to activate the filament runOut option.<br/>It does trigger the G600 Gcode command as soon as the filament is cut. It is the regular command to change filament.</p><p>The sensor snaps on the extruder without any screw. Even the lid is inserted and fixed using a filament "rivet" (see picture).</p><p>The sensor is designed to fit this exact type of switch...</p><p>The two wires of the switch go to the Y_Max connector on the mini Rambo board. They are connected to the S and - pins of the connector. There is no polarity you can swap the two pins !</p><p>Optionnaly you can add to the calibration menu section "Show End Stops" the display of the filament status. (0 = filament inserted)</p><h3>Print Settings</h3><p><strong>Printer Brand:</strong></p><p>Prusa</p><p> </p><p><strong>Printer: </strong></p><p>i3 MK2S</p><p><strong>Rafts:</strong></p><p> </p><p>No</p><p> </p><p><strong>Supports: </strong></p><p>No</p><p><strong>Resolution:</strong></p><p> </p><p>.2</p><p> </p><p><strong>Infill: </strong></p><p>40</p><p><br/><strong>Filament:</strong><br/><br/>none PLA <br/> </p><p><strong>Notes: </strong></p><p>you can add a little "spring" to the sensor by bending the bottom part into hot water.<br/>While doing ths the sensor will stay in place even if no filament is inserted</p><h3>compilation</h3><p><strong>download latest fimware source</strong></p><p> </p><p>Latest firmware is 3.2.3 while writing this note !<br/>It can be found here : <a href="https://github.com/prusa3d/Prusa-Firmware/releases/tag/v3.2.3">https://github.com/prusa3d/Prusa-Firmware/releases/tag/v3.2.3</a></p><p><strong>mod the firmware to activate the filament runout</strong></p><p> </p><p>follow these 3 (or 4) steps : (see pictures)</p><ul><li>in file configuration-prusa.h uncomment this line </li><li>in file pins.h change the FR__SENS pin to 24 (which is the Y_MAX pin)</li><li>in file Marlin_main.cpp add these lines to enable input "pullup" on pin FR_SENS</li><li>optionnaly, activate display of the filament runout switch in the calibration menu </li></ul><p>Category: 3D Printer Parts</p>