Prusa MK2.5S mods for Wham Bam Mutant V2

Description

Update Your Prusa MK2.5S with a Wham Bam Mutant V2 Universal Toolchanger! And Get an Extra 50mm Z Axis Build Height FREE* (see Bonus Option below) A separate version of this project for the Prusa MK3.5S+ is in development, a link to it will be placed here when it is posted to Thingiverse.__ https://www.youtube.com/embed/bql39s__IqQ Learn more about the Mutant here: https://whambamsystems.com/mutant Welcome to the Mutant Invasion! https://www.youtube.com/embed/430jwkZXm-0 These parts are used to modify the Prusa MK2.5S to be compatible with the Mutant universal tool swapping system and to mount the Wham Bam Mutant onto Prusa MK2.5S X gantry. This project ensures that you do not lose any build space on your Prusa MK2.5S. A separate project for the Prusa MK3, Mk3.5, and MK3.5S+ is being finalized. A link will be posted here when it is ready. This project's X gantry hotend assembly parts are also compatible with the Wanhao i3, and other 3D printers where the X gantry is based on 45mm center-to-center dual Linear Motion Rods. Instructions on how to modify your hotend assembly wiring loom to connect to the Mutant V2 can be found here: Note for this modification you will likely need to extend (or replace) the wires in the loom as its path now goes over the top of the Prusa Z axis frame. In order to reach to the bed over the top of the Z axis frame you will need 600mm of wire length as measured from the top of the Prusa controller box to the top of the Mutant base plate connectors. If you are going to extend your existing wire loom, here are two options: • You can purchase (or build your own) extension cables for each component in the hotend assembly. These connect on the controller board side of the wire loom. Here is a source where you can purchase the cable extensions: https://caribou3d.com/en/17-plugs-connectors-cables • You can solder wire to the existing loom to reach the Mutant base plate connectors. I recommend these easy to use soldered connectors (only need a heat gun) to ensure a strong long lasting connection. https://www.amazon.com/gp/product/B083LZS69N Be sure to use the same size and type of wire for each hotend component powered via the wire loom. If you are going to build a replacement wire loom, I would recommend a length of 750mm to run from the controller board connectors to the Mutant base plate connectors. Minimum printed parts required to add the Mutant to a Prusa MK2.5S (recommend printing in PETG, ABS, or PC). • Prusa Syle Mutant X Gantry Plate.stl • MK2.5S-X-end-motor-M.stl (to adjust the end-stop switch position for the Prusa OEM extruder/hot-end setup PLUS • MK2.5S-Short X EndStop.stl (Prusa OEM extruder/hot-end setup) OR • X Endstop Prusa MK2X Series.stl (adjustable for other hot-end setups) This project supports two styles of X end-stop brackets. One for the Prusa MK2.5S extruder/hotend assembly, and another for other hot-ends/devices you may want to use with the Mutant on your Prusa. This Mutant mount will not lose any Z Axis build volume. If you ONLY use the part(s) above, since the Mutant is wider and thicker than the OEM setups for the Prusa Style printers, 28mm of X Axis build space is lost. Resulting in a 220mm X by 195mm Y build space. While no firmware changes are needed for the above, without completing the full mod set below, you will not be able to perform a Calibration > Wizard setup (not normally needed after passing the first time) as the Pinda probe will not find the targets. To have full build volume and full software functionality, complete the rest of the mods below. Restore full Prusa build volume for X & Y: Purchase two 8mm x 400mm Hardened Chrome Plated Linear Motion Rods https://www.amazon.com/gp/product/B07DPGD69D Print the included replacements for the Prusa Z Axis bottom and top STLs. These will move the X Axis ends out by 15mm on each side compensating for the wider Mutant gantry to restore the full 250mm X axis print space. (see photos) • z-axis-top-v2.stl • z-axis-bottom.stl • Prusa Mk2.5S Power Supply Bracket.stl • 8mm x 400mm Hardened Chrome Plated Linear Motion Rods - https://www.amazon.com/gp/product/B07DPGD69D Since the addition of the Mutant adds ~15mm to the front of the X gantry (which would otherwise be a loss of ~15mm on the Y axis), so in order to correct for this, all that is needed is to reposition the Z frame on the two Y axis threaded rods back by the equivalent ~15mm. The reason this is approximate is that your distance from the X gantry rods to the hot-end nozzle may vary in your setup (depending on the hot-end setup you use). When mounting the Prusa extruder and hot-end with the modified parts included here, the offset distance is 15mm. Start by removing the screws that hold the power supply to the bracket on the Y axis. Next loosen the two sets of double nuts that hold the Z frame to the Y axis threaded rods (see photos for details). Reposition the Z frame on the rods back by 15mm. Measure accurately and then tighten the nuts to hold the Z frame in place. Note that due to the Z frame using slots instead of through holes in the frame to attach to the Y axis rods, you will also need to make sure you have the Z frame aligned vertically on the two Y axis threaded rods. Be sure to double check your measurements that the Z frame has been moved the exact same distance on each threaded rod (see photos). Refer to Prusa's assembly instructions for the Z frame assembly steps to be sure you are aligning everything correctly. https://help.prusa3d.com/en/guide/2-y-axis-assembly_88232 Step 11: Where it says "Retain 100mm distance between a washer after counter-nut and the Y-axis corner." You will want this measurement to be 85mm. https://help.prusa3d.com/en/guide/4-z-axis-assembly_90552 Step 15: Once you have the Z frame locked in place use the printed Prusa Mk2.5S Power Supply Bracket part to secure the power supply box to the bracket on the Y axis as seen in Step 7 of the linked instructions below. https://help.prusa3d.com/en/guide/7-psu-heatbed-assembly_93112 Step 7 The following modified Prusa parts for the MK2.5S are needed to mount your existing Prusa OEM extruder/hot-end setup on the Mutant. Except where noted, use all your existing screws to assemble the Prusa extruder/hot-end assembly. • extruder-body-R5M-v2.stl (req. two M3 20mm, one M3 12mm, one M3 10mm screw, and 4 M3 square nuts to mount the extruder body to the Mutant V2 mobile plate) • extruder-motor-plate-R4M-v2.stl • extruder-cover-R5M-v2.stl Center (left to right) the Prusa extruder body part when mounting it to the Mutant mobile plate (see images for mount points). Re-use the rest of your existing extruder parts (extruder-idler.stl, fs-cover.stl. fs-lever.stl, etc.) as those have not changed. Optionally you can use the following two parts to get much better part cooling as well as being able to see the hotend from the front. • extruder-cover-RM5-optional.stl • Part-cooling-fan-optional.stl These are modified versions of the Delta-P fan duct by teookie configured to fit my modified Prusa extruder and motor mounts. Info on this cooling system can be found here: https://www.prusaprinters.org/prints/62523-delta-p-fan-duct-v2-r2-for-mk3s-extruder To accommodate the widening of the X Gantry, firmware changes are required to reclaim the full 250mm printing width. Here is a link the the Prusa GitHub where you can download the latest firmware for your model of Prusa printer. https://github.com/prusa3d/Prusa-Firmware Instructions on how to compile and flash the firmware to your printer are not provided here. There are many great tutorials for this that can be found only and via YouTube. To get the firmware to recognize the wider X gantry, you will ned to make the following changes: // Travel limits after homing #define X_MAX_POS 265 #define X_MIN_POS 0 #define Y_MAX_POS 210 #define Y_MIN_POS -2.2 #define Z_MAX_POS 210 // You may be able to increase this to 220 depending on the hotend setup you have Depending on the extruder/hot-end setup you attach to the Mutant you may also need to modify theses settings: #define X_PROBE_OFFSET_FROM_EXTRUDER 23 // Z probe to nozzle X offset: -left +right #define Y_PROBE_OFFSET_FROM_EXTRUDER 5 // Z probe to nozzle Y offset: -front +behind #define Z_PROBE_OFFSET_FROM_EXTRUDER -0.4 // Z probe to nozzle Z offset: -below (always!) The values listed above are for the Prusa OEM extruder/hot-end offset settings. With the full mods and firmware changes, the Prusa Mk2.5S (with the Mutant and OEM extruder/hot-end mounted) will pass the Prusa Calibration setup Wizard. The key for other extruder/hot-ends is to have the Pinda probe mounted in the same location as for the OEM, otherwise you will have to adjust the probe offset settings above to compensate for the change in position so that the auto bed leveling will perform accurately. ###Bonus Option: Get added Z height for FREE (almost*)! By printing the optional STLs listed below and reusing the two 8mm x 370mm liner motion rods that are removed from the X gantry when you do the full mod set above, you can add an additional 50mm of Z axis build volume! The 370mm rods replace the existing 320mm rods, and the parts below allow the Z axis to travel the full height of the longer rods with no alignment issues. The X gantry motor and idler brackets have been 'flipped' to accommodate the height differential between the shorter Z axis motor threaded rods and the longer linear motion rods. Optional-MK2.5S-X-end-motor-M-tall.stl Optional-MK2.5S-X-end-idler-M-tall.stl Optional-Z-axis-top brackets-M-tall.stl Optional-MK2.5S-X-EndStop-M-tall.stl *The one additional item required is to replace the X end stop switch with a smaller version to be able to fit on the redesigned X end motor bracket. A switch with a width of 13mm or less will work. Here is an example from Amazon: https://www.amazon.com/Cylewet-25Pcs-Switch-Arduino-CYT1073/dp/B073TYWX86 (this is a pack of 25 pcs for $7, I did not find an option for fewer pieces in this size) The only other change is to set the firmware Z axis height to 260. #define Z_MAX_POS 255 // 5mm less than actual so that calibration will pass Congratulations! You now have added build volume to give you a total build space of 250mm X, 210mm Y, and 260mm Z. __If you would like a way to store your Mutant Mobile hotend assemblies and other Mutant devices while not on a printer check out my Mutant Workstation mounts here: https://www.myminifactory.com/object/3d-print-mutant-workstation-mounts-149200 __