MMU 2s ugrade to MMU 3without upgrade kit3  

RE:

Posted by: @pete-2

Hello, as the leading time for upgrade kits for Mk4 are stoll long, i was just wondering, if it makes sense to print the upgrade parts, buy the cable, the PD- board and some ptfe tubes with 2.5mm Id and try to get it running. Offcourse updating in 10 weeks when my recently bought upgrade kit arrives. I have a mmu2s and a RMU lying around. Anyone tried and knows, what is missing to go this way and if it makes sense ?

Peter

I accomplished most of the MMU2S -> MMU3 upgrade using printed parts from Printables and some odd hardware I had lying around. However there were some stumbling blocks:

* E3D collets, you need 15 of them and cheapest I could find was $2 each. These aren't the same as the normal collets $5 for 100 units. The E3D collets are slightly smaller and more flexible. The cheaper collets you find on aliexpress are incompatible with the STL files on Printables.

* PTFE tubes, the internal diameter has changed (again).

* Wiring harness, new electronics board, and voltage-correction board.

In the end I admitted defeat and bought the upgrade kit for $80. It was financially cheaper to buy the kit than to source the parts separately but mostly because of the E3D collets. If I could have found a cheap supply of E3D collets it would be a different story.

RE: MMU 2s ugrade to MMU 3without upgrade kit3

Those E3D collets caused me some grief too. All I can find at a reasonable price are the larger ones which require a 6mm hole to fit in, whereas the E3D ones need a 5mm hole.

I modified the drawing for the segment-R4 to take the larger more readily available collets - if anyone is interested I can publish it on Printables?

RE: MMU 2s ugrade to MMU 3without upgrade kit3

This would be very cool. Where do you get the bigger collets for a reasonable price?

RE: MMU 2s ugrade to MMU 3without upgrade kit3

Model is now on Printables, and my source for the larger collets (Amazon) is noted below too. Hope that helps.

https://www.printables.com/model/852337-modified-segment-r4-for-mmu3-buffer/files

https://www.amazon.co.uk/gp/product/B0CRTRLB7M

RE: MMU 2s ugrade to MMU 3without upgrade kit3

Thank you !!!!

RE: MMU 2s ugrade to MMU 3without upgrade kit3

Is there a source where i can find a complete overview, what's in the mmu2 - mmu3 upgrade kit ?

I read from a small magnetic ball in the selector. As i modded my MMU2s already before, i perhaps just change the PTFE tubes, the buffer, PD-Board and cable ??

RE:

I have yet to see a full list of the parts included in the MMU2S to MMU3 upgrade kit for the Mk4. It is very frustrating to not know what you will receive for sure. I only bought the Amazon collets and spent a good half a day modifying the segment to take the larger size. Then I printed all ten of them. Then my kit arrived and I found it included the ten smaller 5mm collets for the buffer anyway. So I could have just printed the Prusa segments.

I can tell you that the upgrade kit includes ten of the E3D collets, five small bearings and the shafts for the buffer cassettes. So I wasted time printing out the shafts too.

Oh, and you do need the bearing ball from the kit. The original MMU2S ball is stainless steel and is non magnetic. The one in the MMU3 upgraded kit is ferrous and will stick to the magnet.

RE: MMU 2s ugrade to MMU 3without upgrade kit3

Has anyone experience if it is possible to install the mmu2 to a non-modified nextruder ?

RE:

So it works !

I printed all the parts, bought the cable and PD-board.

Without modifying the nextruder and  with x19 mod. https://www.printables.com/model/564378-mmu3-idler-mod helps to mount the idler.

Now i wonder, if i will update the nextruder now that all works and if i need my kit.

What will be my benefit to now?

RE:

There are many changes that are not in the printed parts.  Time and cost wise my suggestion is buy the kit.   

I just assembled my mmu2 to MMU3 upgrade.   Things I can remember that are new and not printed.

• Magnet and ball in selector.  The new ball is magnetic while the old one was non-magnetic stainless.
• They provide new brass bushings for the selector.  Many of us had to glue the old ones in and getting them out without damage for reuse is tough.   
• The metal mounting piece for the idler.  Along with set screws.  
• The PD card and cable to connect to the printer. 
• New front selector plate where the Festo fitting goes.
• New festo fitting with 2.6mm ID. Bigger than before  Good luck tracking these down.  
• 2.5 mm id PTFE tubes.
• New cutting blade design x 2.
• Length of some screws change. 
• E3d collets to hold the tubes in.  5 on the MMU, 10 on the buffer.  
• bearings and pins
• New screws and nuts.  Some of the screw lengths change.
• zip ties
• warning label and ID/product label. 
• Using the wrong length screws when mounting the circuit board can lead to emi problems from the notes.  

Nextruder parts, MJF process parts are better for wear and temperature. 

• 4 new type/size screws for the idler-sensor assembly
• All the idler parts.  Idler is strengthened. 
• A new magnet for the idler assembly to trigger filament loading.  A very small magnet. 
• New main plate with O-ring to seal the gear/grease chamber.  2 of the mainplate and o-ring are supplied.  You will have a spare. 
• A new festo fitting with 2.6mm ID.   

Plus some spares. 

RE: MMU 2s ugrade to MMU 3without upgrade kit3

I forgot the rubber bumper button in the MMU...