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MMU2 - MMU2S  

Jakub J
New Member

What are differences MMU2 - MMU2S? I got upgrade but

I dont know if I finished it. (It is years ago)

I have onlyMMU unit extruder not assembled yet.

Thank you

Posted : 29/03/2022 5:42 pm
Eminent Member

It's been a while but IIRC there are no hw modifications going from MMU2 to S on the MMU body itself. The S upgrade did come with a different buffer system (large plastic walls) that replaced the MMU filament holder arms and maybe a new sensor for the MK3 extruder but that's about it.

The main difference is firmware-side so you didn't have to manually set the distance between the MMU unit and the MK3 extruder as it would do it automatically.

Posted : 29/03/2022 7:47 pm
Estimable Member

Wouldn't the firmware work on either MMU2 or MMU2S?

I never built the filament buffers. I use rewinder dryboxes. I never considered the buffers as part of the MMU2S, I just thought they were convenience add-ons.

Posted : 10/04/2022 1:18 am
Eminent Member

It's been awhile and it's usually irrelevant so I could be remembering wrong. I want to say that the MK3 -> MK3S and the MMU2 -> MMU2S were congruent things and depended on whether you had the MMU2 or not. If you didn't have an MMU2 then you just got MK3->MK3S extruder housing parts and sensor; if you did have an MMU2 then you got the MMU2S upgrade kit instead which included the sensor (that non MMU2ers also got) and the new buffer system (which i also never used anyway). The MMU2S 'upgrade' seems so lackadaisical because it was just some extra stuff for MMU2ers while the main point of the upgrade period was the sensor and new extruder housing revision.

I don't know if it's really necessary for the 'newest' firmware, but the MMU firmware hasn't been updated since 2019 so /shrug.

And while the buffer system is also not my cup of tea, it is part of the upgrade kit. The old hinged arm thing worked but was very annoying to load.


I want to say if you bought your printer after the MK3S upgrade period then you don't need the MMU2S upgrade kit. Unless you just really want those black plastic walls.


Posted : 10/04/2022 2:14 am