Prusa CORE One/+/L Bufferless MMU3

This was designed for the Core One L, but this will fit any Core One, the length of the T slot can be shorter. See the Bufferless MMU3 on Core One w/ Rewinder Spools.

I have included all the parts I used, so you don't need to find them. The pics should be self explanatory.

The ptfe guide, 2 versions provided, push tube through and the M5-4 fitting. I used the M5-4 as the original concept designer used it, but I can't find any benefit at this point. Supports are required, use my 3mf for easy support removal.

PTFE installed per this designer. Works great, need a round file to clean-up the edges of the hole. Added the Y splitter, working great. You'll see before and after pic.

If you use cardboard spools, use the spool inserts from Inner Diameter Adapter for Cardboard Spools

Custom Firmware

If you want to run PTFE longer than 1000mm, you can flash my custom firmware to the MMU3, version 3.0.4, I changed the parameters so you can send the size you want up to 3000mm, which you should not be need. Credit to here. My PTFE length is 1080mm. You can not change it through the printer, send it through start g-code as below.

You can add the following to the start of your GCode just the once (each time you need to change it, saves each time)

M708 A0x22 X####

where #### is the length in mm. 

Start G-Code Correction

Prusa has decided you should print at 20C for PLA, which is ridiculous, the fans will run 100% and the print will fail. This change puts the filament profile back in control.

{if (is_extruder_used[0] and filament_type[0]=="PLA") or (is_extruder_used[1] and filament_type[1]=="PLA") or (is_extruder_used[2] and filament_type[2]=="PLA") or (is_extruder_used[3] and filament_type[3]=="PLA") or (is_extruder_used[4] and filament_type[4]=="PLA")}

M141 S{chamber_temperature[initial_tool]} ; set nominal chamber temp to listen to filament profile

;M141 S20 ; set nominal chamber temp

{elsif chamber_minimal_temperature[initial_tool]!=0}

MMU3 Lite Install

• Installed per Prusa, Nextruder mods too

• Prusa Core One L cable install

Materials

• 2 - 500mm T Slot 2020

• 2020 Series Sliding T Nuts Metric M3

• M3 x 8mm

• 6 - Strong Rare Earth Magnets 30x10x2mm

• 10 - 608 Yellow Jacket Bearings

• 800mm Prusa Community Cable

• M5-4 (Optional)

• 2.5mm ID 4mm OD Tubing

Credit

Parts that weren't listed under the Remix section are from these original designers and/or remixes,  you can chase the rabbit hole.

Remix not listed below, designer picked a weird license