Printrbot Metal Plus MMU (Prusa Inspired)

cults3d

This is my upgraded Multi Material Upgrade (MMU) for the Printrbot Metal Plus, inspired by the innovative work of Josef Prusa and his MMU design. I've remixed parts from several talented individuals to create this upgrade: * Josef Prusa: I used his MMU as a base to develop mine. * SpannerHands: I incorporated his MP spool holder design into the extruder mount. * Walter: I utilized his printable housing for printrbot extruder gears. Please explore their work and check out their profiles. Important Note: This modification limits the Z-axis travel to 220mm from the standard 254mm, which wasn't an issue for me since I never used the full range. If you're considering this upgrade, please be aware of this limitation. This MMU has been optimized to fit my modified Printrbot Metal Plus with SpannerHand's mods, which involved cutting the X-cart and using a blower fan for part cooling. If you choose to install this mod, you can either use SpannerHand's modifications or keep your X-cart uncut; however, be aware that the Z sensor may not align properly in the latter case. Update - 08/04/2018: I've since removed this mod from my Metal Plus due to issues with printed extruders and opted for a new project, the D-Bot. If you decide to build this MMU, I wish you success; please share your results! Update - 07/02/2018: For wiring guidance, refer to the wiki page at http://reprap.org/wiki/Adding_more_extruders. Update - 28/01/2018: I've created mounts for E3D v6 and UBIS 13S hot ends; these haven't been extensively tested but appear to fit properly. Use them at your own risk, as I'm unsure of their performance with the MMU. I've also remixed parts from SpannerHand's Printrbot Metal Plus mod to accommodate either hot end with a blower fan and lower ducts. Hardware: This upgrade is designed for my Printrbot Metal Plus with a single extruder, mounting to the metal cart using M3 bolts into M3 inserts. The extruder mount uses SpannerHands' idea of attaching to the metal frame and features cable tie holes for securing the assembly. To ensure one filament clears the guide before inserting another, I've used clear PTFE tube; this also helps identify potential issues and prevents damage. Electronics: I'm using an Arduino Mega & RAMPS 1.4 board as my main controller, which supports only two extruders. To accommodate additional extruders, I'm employing Printrbot's Extrudrboard connected to the AUX-2 pins on the RAMPS. Parts List: * Prometheus V2 Hot End: https://www.distechautomation.com/products/prometheus-v2 * Brass inserts M3 & M6: https://www.ebay.co.uk/itm/M3-M4-M5-M6-Threaded-Solid-Brass-Press-in-Barbed-Inserts-for-plastic/262993790868?var=562002386626&hash=item3d3ba6c794:m:mOHTFRbrYIVeJt2c76sT51w * M6 pneumatic fittings: https://www.aliexpress.com/item/10Pcs-PC4-M6-Pneumatic-Straight-Fitting-Connector-for-4mm-OD-Tubing-M6-6mm-Reprap-For-3D/32668216080.html?spm=a2g0s.9042311.0.0.3a8KMo * Extruder gear set: https://printrbot.com/shop/gear-head-extruder-gear-set/ * Gear set bearings: https://www.aliexpress.com/item/10pcs-Lot-MR85ZZ-Double-shielded-Miniature-Ball-Bearings-5x8x2-5mm-for-3D-Printer-Model-Making-Deep/32812874077.html?spm=a2g0s.9042311.0.0.3a8KMo * Clear PTFE: https://www.aliexpress.com/item/3D-printers-1M-2-4mm-Clear-PFA-PTFE-Tube-Teflon-PiPe-J-head-hotend-RepRap-Rostock/32611337704.html?spm=a2g0s.9042311.0.0.3a8KMo * Printrbot Extrudrboard: Currently Unavailable