Printable components MMU3 for MK4  

RE:

Assume you have already looked for yourself?

They are easy to find on Prusa's website but the updated parts and specific parts for the Mk4 nextruder setup haven't been released yet though.

RE: Printable components MMU3 for MK4

You will be able to find them here: https://www.printables.com/@Prusa3D

And as Steve said, the new parts for the MMU3 for MK4, and the new Nextruder parts for the MK4 have not been released yet.

RE: Printable components MMU3 for MK4

yeah, I looked for myself 🙂

I'd like to print the correct part and not have to reprint some things because of the updates 😉 Then I'll wait patiently 

RE: Printable components MMU3 for MK4

Hello, printables.com (MMU3 Parts) shows this notice:

Update in progress! Printable parts for MK4/MK3.9 MMU3 will be available soon.

RE:

Bgcode files for Mk4 have been issued.

From Printables:

Update in progress! 

G-codes for MK4/MK3.9 MMU3 are already available in the “Files” section
Printable parts (STLs) for MK4/MK3.9 MMU3 will be available soon together with description of the changes.

RE: Printable components MMU3 for MK4

Nice. It looks like almost every part of the MMU3 was updated. I'm glad I didn't start printing until now.

RE: Printable components MMU3 for MK4

Yeah, most parts seemed to have been bumped from R3 to R4, but it's difficult to see any differences between those and the R3 versions when looking at the bgcode files.  Looking forward to seeing the description of the changes, to see how much I've got to reprint!

A few obvious differences: the buffer segments look quite different, the buffer holder seems to be mirrored(?), and there's a new part in the 'UNIT2' bgcode.

RE: Printable components MMU3 for MK4

I've also compared "old" and "new" Chris and can't see much change for some parts. I guess though that I will probably reprint all the R4 parts so as to start off with the latest iterations from Prusa. 
I shouldn't have gone so early with the parts prep back in September. I note though that 2 x 400 gr spools of filament are included in the $89 upgrade so at least won't have to buy another reel of Prusament.

RE:

I've never known Prusa to change a revision number on a part without something being different. Now, whether some of the new R4 parts have significant enough changes to make a noticeable difference from the R3 parts, I don't know. But I'm sure there will be someone out there who will try the R3 parts and see what happens.

Someone on the Prusa discord has noticed some differences in a few of the parts already. The cutter, and the electronics cover, for example.

RE: Printable components MMU3 for MK4

Hi all

I just looked at the parts list for the MMU3 and noticed a part where I need an M5 threaded insert. I ordered the mmu2s->mmu3 upgrade for MK4. Will this part be included or do I have to order it separately and press it in?
I can't find any information about it either. Maybe I just overlooked the information. Maybe someone has information about it.

RE: Printable components MMU3 for MK4

If you have an MMU2 the Selector Front plate should have an M5 insert in it, and I believe this front plate will go on the MMU3, however, when I got the latest set of plastics for the MMU3, there was a front plate with insert in the kit...
regards Joan

RE: Printable components MMU3 for MK4

Posted by: @jay-11

I've never known Prusa to change a revision number on a part without something being different. Now, whether some of the new R4 parts have significant enough changes to make a noticeable difference from the R3 parts, I don't know. But I'm sure there will be someone out there who will try the R3 parts and see what happens.

Someone on the Prusa discord has noticed some differences in a few of the parts already. The cutter, and the electronics cover, for example.

Yes, the electronics cover appears to be deeper, and the Selector Finda appears to have an extra v-shaped strand of filament on the top.  Did they spot anything else on the Discord?

I've just printed out some of the parts in the 'BUFFER1' bgcode (cancelling the bits I didn't want).  I realised I'd forgotten to print the Segmenter 🙄 , I wanted a couple extra PTFE clips, and if I'm not planning to mount the buffer alongside the printer I assumed I could replace the Buffer Holder with a sixth Plate Holder.  Comparing the printed parts side by side, despite the bump in revision numbers, I can see no difference in the new plate holder or PTFE clip, apart from changes in the revision markings.

I'm about to send the 'UNIT2' bgcode to the printer, since it will get me the new electronics cover and Selector Finda, and the extra part that wasn't in the MK3S+ files.  And I'm guessing they've fixed the loose pin issue in the Idler, although I had already printed a version that has been modded by an end user.

RE: Printable components MMU3 for MK4

Ah yes - the Blade Holder seems to have been changed too, to go with the Selector Finda change, apparently to angle the blade slightly.

RE: Printable components MMU3 for MK4

I noticed the position of the blade holder on the Selector had changed. I had hoped they improved the Finda holder on the Selector as well, since a few people were breaking them during assembly, but I can't see any differences.

I'll start printing the parts today in PETG to compare to my R3 parts I previously printed. When they release the STLs, I'll be printing the final parts in ASA.

RE: Printable components MMU3 for MK4

Posted by: @jay-11

When they release the STLs, I'll be printing the final parts in ASA.

I guess I should do the same, since I made all the other printer parts out of ABS to be able to withstand higher temperatures.

So I've converted the supplied bgcode to ASCII, and then edited all the bed temperature (M190, M140) and nozzle temperature (M104, M109) commands to suit my preferred ABS settings.  I also changed all the relevant 'PETG' comments to 'ABS'.  So far so good - my UNIT1 gcode seems to printing properly with ABS loaded.

The two pieces in UNIT1 have those troublesome recessed squares on the bottom, which require perfect bridging on the second layer otherwise the print gets messed up.  So I've manually tuned the print speed (down to 50%) and they've printed nicely.  Maybe they would have done at 100%, but I wanted to play safe.  For my first attempt I also tried adding a bit of fan, but I got a bed temperature crash, I think because those first few squares are close to the bed thermistor below, and the fan meant that the thermistor temperature dropped.

RE: Printable components MMU3 for MK4

I don't recommend this approach after all ^^

The cooling profile for ABS is quite different from PETG, so although the parts printed well, I don't trust the strength because the fan was running a lot faster than it should have done for ABS.  Since there too many fan speed commands (M106) to edit them manually, I'm just going to wait for the STLs to arrive and slice them properly for ABS.

RE: Printable components MMU3 for MK4

Moving this here, as it seems like a better thread for it than the 'shipping soon?' thread.

My MMU3 arrived this morning.  I've been tinkering with a modified model of the main plate, to match the MJF version supplied with the MMU3 (actually there are two copies in the kit, and two O-rings).  I started with Volker's modified main plate, which is the result of his experiments with the MMU3 on his MK4.  He created a slightly smaller hole in the lower guide post so that the filament feeds cleanly into the top of the nozzle tube, and indeed that does seem to be what Prusa have done with the MJF version. 

My earlier draft was quite close, but with the real thing in my hands I've been able to see details that weren't clear in the photos, and tweak the model for a closer match.  I've printed a version with 0.05mm layer height, in some PC-CF (this stuff), and I'm pleased with the result.  The PC-CF is lovely stuff to print with.  I used the standard Prusament PC Blend Carbon Fiber profile, which uses a slightly higher nozzle temperature than the spool recommends, but I felt that was OK because I usually bump the nozzle temperature for my ObXidian nozzle anyway.

If the PC-CF is all it's cracked up to be, it should be closer to the MJF version in terms of longevity, and I'll probably build my MMU3 with my printed version just to see how it performs.  Of course, it's still possible that Prusa will include the main plate when they publish the STLs for the MMU3 MK4 version.  But they've said they were having trouble with the part wearing out, and the fact that they opted to use MJF in the end might suggest that there weren't any suitable FDM alternatives, or it might just be that they felt that not everyone would be happy printing the more hard-wearing filaments.

Anyway, I'm still looking forward to the release of the STLs.

RE: Printable components MMU3 for MK4

I am waiting on the STL's too. The 5mm collets Prusa use in the buffer cassettes are just not available in the UK so I have to settle for the Amazon collets which need a 6mm hole. Of course I spent half a day converting the R3 cassette segment into a drawing and reworking it to accept the larger collets. I then printed out ten of them to make the cassettes and now the design has been changed to allow more room in the buffer for the Mk4 with MMU3. So all that is now in the bin and I'm stuck waiting for the cassette segment STL - unless anyone know how I can extract it from the released .bgcodes?

RE: Printable components MMU3 for MK4

congratulations, it looks like excellent work.