1. MMU History and Printer Compatibility

Step 1 of 12 (Chapter 1 of 18)

Contents

Comments

⬢

Welcome to the MMU3 guide! There were several generations of the Original Prusa Multi-Material printing solution. Verify you are looking at the correct guide for your MMU unit and your printer.

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MMU1 for MK2 and MK2S printers (introduced in 2016-2018)

It used four separate extruders feeding one nozzle.

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MMU2 for MK2.5 and MK3 (2018-2019) Five filaments feeding one direct-drive extruder.

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MMU2S for MK2.5S, MK3S, MK3S+ (2019-2023)

Introduced a chimney on the extruder with the IR-filament sensor.

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And finally, the current model:
MMU3 for MK3S+, MK3.5/S, MK3.9/S, MK4/S and CORE One.

MMU3 is the one we will be dealing with in this guide.

MMU3 Assembly (MK3S+, MK3.5, MK3.9/S, MK4/S, CORE)

1. Introduction
2. MMU2S Disassembly (UPG)
3. MMU2S Buffer Disassembly (UPG)
4. Idler Body Assembly
5. Selector Assembly
6. Pulley Body Assembly
7. Spool holder Assembly
8A. Cassette Buffer Assembly
8B. CORE One Buffer Assembly
9A. MK4/S, MK3.9/S Nextruder mod
9B. MK3S+ / MK3.5 Extruder mod (KIT)
9C. MK3S+ Extruder (UPG)
9D. CORE One Nextruder mod
10A. MK4/S, MK3.9/S Setup and Calibration
10B. MK3S+ Setup and Calibration
10C. MK3.5 Setup and Calibration
10D. CORE One Setup and Calibration
11. First Flight

Comments

lfish

•

For MK3.9S, I'm planning to print the "MK4S MMU3 G-codes". Please add "3.9S" instructions or add it to the appropriate title.

MagnusVesper

•

Be sure you have allen wrenches (the kind with a round-ish end) instead of just grabbing a random hex wrench of the right size. This involves a lot of screws with very little clearance, so you really need allen wrenches.

duenkich

•

I'm unable to figure out, what I need to print for the MK3S+/MMU2S upgrade to the MMU3... Does anyone know that?

David B.

•

Apart from obtaining the upgrade package with the hardware components, you will need to print these files:

https://www.printables.com/model/531604-mmu3-printable-parts/files

Alexihans

•

It seems to me that the MMU3 complete is not ready for the MK4 as i only can find it under the upgrades,
or is what is mentioned a full kit?

Jan Kratochvíl

•

Hello. You can find MMU3 for MK3.4/MK4 here: https://www.prusa3d.com/en/product/original-prusa-mmu3-upgrade-kit-for-mk3-9-4/

Alexihans

•

Hi Jan Thanks for the link, then i have looked at it, but looking at the assembly manual, it only referes to 3XX and it is based on upgrading from the MMU2 which can be a little confusing mixing reused and new parts. Also looking at the artikle about MMU3 it seems like it is not fully ok yet. I will wait some more times before i get one. Do you have any experience wit it?

Jan Kratochvíl

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This kit is for MK3.9/4 users, who dont have any MMU, so it includes all electronics motors and other stuff. You can buy it with already printed parts, or you can print them by yourself (in that case, package contans 2x 400g of PETG). Then you can go to https://prusa.io/0ld1 to assembly guide. Part 9A is modding Nextruder on MK4.
MMU3 on MK4 is thoroughly tested and currently it is looking very good :-)

Shane

•

For the full kit version it is included. For the upgrade kit, it could be that people print out the plate then apply a sticker or label over the part so it lines up.