MMU2s Electrical Cover with On/Off Switch

prusaprinters

<p>This is the 6th and last installment of my major upgrade to the MMU Head Unit. I am working upgrading the extruder as part of a separate upgrade and a new almost silent and compact auto rewind system for the filaments.</p> <p>Sometimes I don't want to use my MMU and until there is a Firmware update that will allow someone to bypass the MMU the best way to do that is by disconnecting the control cable between the Einsy and the MMU. That is a pain. In addition I found the cable management system with the stock cover to be lacking.</p> <p>Goals:</p> <p>-Incorporate a switch so that the MMU can be disabled and the MK3s can run as normal.<br/> -Improve the cable management system and overall aesthetic of the cover.<br/> -Printable without supports<br/> -Reduce parts count as much as possible.</p> <p>Changes:<br/> -Designed a custom PCB that will switch off the signal from the MMU to the Einsy. When the transmit and receive signals are interrupted the Einsy does not recognize the MMU after a reboot. There are 5 parts on the PCB but as an assembly with cable the net parts increased by 2. I will have the PCB's available for sale listed below as soon as they arrive but if you want to roll your own the files are here. <a href="https://github.com/jfromel/MMU2s-Switch">https://github.com/jfromel/MMU2s-Switch</a>.<br/> -Increased the depth of the cover to accommodate the new switch and cable management.<br/> -Added a back to the cover with 4 zip tie holders.<br/> -Cut inserts into the sides for the cables.</p> <p>There are two versions depending on if you want the extra switch or not. The spacer STL file is to mount the switch PCB to to the main board.</p> <p>Update 04/11/2020:<br/> Changes as follows, reduced zip tie holders to 3 and positioned them for better cable management. Increased the size of the openings for the USB and reset switch and changed the profile of the side holes for the ribbon cables for easier printing. Finally added a Logo. If you don't want the logo the original file still works fine.</p> <p>Update: 02/22/2020:</p> <p>I have the custom PCB's in and they fit great, I got 10 prototype boards so there are 9 left, if there is any demand it's easy to order more. I made a slight modification to the model by changing the profile of the USB input so the bridge was less than 5mm (was almost 10mm) and changed the way the board mounts so the top has all socket heads and no washers (just an aesthetic thing). Original files are still awesome.</p> <p>Modifications based on the source files found here. <a href="https://github.com/prusa3d/">https://github.com/prusa3d/</a></p> <p>Parts Needed:<br/> -Custom PCB (roll your own with the files here or buy one from me, includes jumper cable and all needed hardware) <a href="https://fromelelectronics.com/products/switch-upgrade-for-prusa-mmu2s">https://fromelelectronics.com/products/switch-upgrade-for-prusa-mmu2s</a></p> <ul> <li><a href="https://amzn.to/31R95ks">https://amzn.to/31R95ks</a> 5 Pin IDC cable 10cm (if you can find a shorter one let me know<br/> If you don't have the screws in your parts bag....<br/> <a href="https://amzn.to/2UPqCb0">https://amzn.to/2UPqCb0</a> Small Socket Head Assortment<br/> You will need.<br/> -M3 15mm Socket Head bolt (or similar).<br/> -M3 Hex nut. </li> <li><a href="https://amzn.to/3bB8kjB">https://amzn.to/3bB8kjB</a> Long Socket Head assortment You need 2 M3 30mm Socket Head Cap Bolts</li> </ul> <h3>Print instructions</h3><p>Paramount PLA 200/60<br/> Prusa Slicer 0.2 quality<br/> No other changes no supports</p>