MM3 and Prusa Enclosure - how did you set it up?
Before going for a purchase, I'd like to ask the forum for opinions: I have my printer (mk4, but for this question it is not relevant) inside a Prusa enclosure. I am very much interested on how the filament feeding is done with the MMU3, e.g., where are the cassettes mounted (inside, outside?), are the filament rolls in a box? Plain air? etc etc
My current setup has the single filament spool mounted on top of the box, so that the inside is exclusively used by the printer.
anticipated thanks for sharing your experience
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While this is technically for the MMU2S, I believe the instructions are supposedly the same for MMU3 and are currently being updated and should be released soon. I think the buffer feet will have to be modified as if I remember correctly the MMU3 buffer is a little wider. But it also has a built-in foot in the cassette holder, so might not even be needed.
6. Hinged Lid (add-on) | Prusa Knowledge Base (prusa3d.com)
RE: MM3 and Prusa Enclosure - how did you set it up?
When I assembled my enclosure it came with a bracket that allowed me to mount a single roll of filament on the top right corner. But in the printables files there is an .stl of a universal bracket that will hold a roll in any of the 4 corners on either side, (I haven’t printed them yet) so in theory you can hold up to 8 rolls inside the enclosure! This will serve double duty, make the whole unit more compact with the MMU and dry the filament as well with the raised ambient heat of the printer while it’s running. My enclosure stays at around 10% humidity when the printer is running.
RE: MM3 and Prusa Enclosure - how did you set it up?
I've just finished assembling my MMU3, and I've mounted the buffer on the underside of the hinged lid. I've also fitted spool holders to the front four corners (two in the top right corner) - the two on the left side will obstruct the LED light strip a little bit, but it still illuminates the print bed fairly well. So my whole setup - buffer + 5 spools - is all self-contained within the enclosure. I'm going to need to buy some longer lengths of PTFE tubing to reach fixed points in all four corners - currently the ends of the tubes are all 'floating', but that doesn't seem to matter. And I can probably shorten the tubes between the segments and the MMU3 itself. I'm not yet sure how usable the buffer will be in this location. It's probably easier to have it outside and more easily accessible, but it works, and I value the fact that it's not taking up any more space.
My spool holders are variations of a model that I've already published on Printables, with screw-in spindles so they can be stowed when they're not being used - I plan to post the updates any day now. And my buffer mount is something I've made in the last couple of days - basically I've replaced four of the buffer holders with versions that screw to the lid using the existing screw holes in the lid. I also plan to post those on Printables.
Assembling the MMU3 was very satisfying - the instructions were clear and everything fitted together perfectly. I think I got more enjoyment from this build than I did from any of my previous printer builds. I did a quick test print in two colours and it was an absolute joy to behold! It's a little mechanical marvel 🙂
RE: MM3 and Prusa Enclosure - how did you set it up?
Chris, could you post some pictures?
Thanks, Tom
RE: MM3 and Prusa Enclosure - how did you set it up?
Are you not concerned about changing the length of the tubes to the buffer? I thought this was a huge issue with loading to the MMU unit according to Prusa and a lot of testing went into the setup to fix this issue to come up with the exact length that created the right amount of tension for the unit to be able to grab and load the filament.
I'm going to need to buy some longer lengths of PTFE tubing to reach fixed points in all four corners - currently the ends of the tubes are all 'floating', but that doesn't seem to matter. And I can probably shorten the tubes between the segments and the MMU3 itself.
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Sure. Keep in mind it's a work in progress, so the photos will be better once it's all finished. I've ordered some more PTFE tubing so that I can have continuous runs from the segments to the fixed load points on the front of the enclosure.
This is the smaller 1kg version of my spool holder, showing the spindle in the 'stowed' position when it's not in use.
I'm just now working on numbered load points. I'll make a double version for the top-right position where I have a stronger spool holder that can carry 2x1kg. For the two spools in the bottom corners I'm using this model, but will modify it to include segment numbers like the one in the photo below. I've modified this one so that the PTFE tube exits towards the corner, rather than towards the centre, since this will make it easier to hide and secure the tubes in the corners of the enclosure.
RE: MM3 and Prusa Enclosure - how did you set it up?
Are you not concerned about changing the length of the tubes to the buffer? I thought this was a huge issue with loading to the MMU unit according to Prusa and a lot of testing went into the setup to fix this issue to come up with the exact length that created the right amount of tension for the unit to be able to grab and load the filament.
I'm going to need to buy some longer lengths of PTFE tubing to reach fixed points in all four corners - currently the ends of the tubes are all 'floating', but that doesn't seem to matter. And I can probably shorten the tubes between the segments and the MMU3 itself.
Well I wasn't until you wrote that! I guess I'll find out. If it causes problems I'll revert to the supplied tubes and just leave the ends floating again. For now they are just zip-tied into the top corners of the enclosure. They're about 20cm short to reach the original load point, and about 35cm short to reach the lower mounting points. That's about half the length of the supplied tubes, so I guess if extra friction is going to cause a problem, then adding 50% will be likely to show it!
I guess I could put all the mounting points together in the top corners - three on the right, two on the left - so that they're all only 20cm longer than supplied. I could add a third feed point to this model.
RE: MM3 and Prusa Enclosure - how did you set it up?
Actually, the tubes are plenty long enough to reach load points in the top corners after all - I hadn't pulled all the slack. So perhaps a double mounting point in the top left, and a triple mounting point in the top right will work - something like this. One of the screw holes needs attention, but other than that this should fit in place of the original load point.
RE: MM3 and Prusa Enclosure - how did you set it up?
Curious to see how it works out for you. Found the line from Prusa about it from the blog post, but there isn't much detail into the exact issue or what they changed.
Also wondering how having the spools on your spool holders will work out as that seems to be fairly tough pull and a lot of friction compared to the mmu spool holders, where prusa mentioned issues if any of the wheels were damaged after a lot of uses would cause issues due to the increased force needed to rotate the spool.
Would love to implement what you have though if it works as I'd much rather have everything inside the enclosure.
Spool holders – The spool holders and filament buffer remain the only components where we are still doing significant changes. Our tests show that on the MK4, where the length of the unloaded filament is slightly longer compared to the MK3S+, filament tension in the buffer and from the spool holders impacts reliability. We are testing different setups to see which work the best.
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Yeah, I guess I'll find out soon enough. And yes, a hanging spool holder is likely to create more friction than the supplied versions. So far so good though - I printed this 'three tube' version using the earlier 'two tube' version, and the MMU didn't seem to have any issues. But there were only two filament changes! I need to finish the 'two tube' version for the left hand corner, and then set a longer job going with five colours.
The odd numbering sequence in this photo is so that the second spool in the top position isn't being pulled sideways.
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I've spent the day tweaking the setup, and I'm starting to think it might work.
I flipped the buffer unit over, to create a little more space in the top right corner where I'm more likely to mount two spools if I want to use all five slots, or a 2kg spool if not.
The supplied PTFE tubes are just a little bit too short to allow the lid to open up fully vertical when the loading points are in the top corners, which makes pulling the segments out to load a new filament rather tricky. I do have some more tubing on the way, and I had intended to add 10cm or so to each tube to solve that problem, but I've found what I think is a better solution.
This is a loading fork that allows the filament to be loaded without having to remove the segment. It means that I only have to crack the lid open far enough to get the fork into the slots (from the opposite end of the buffer to the segments), and it makes loading the filament so much easier. Unfortunately the fork doesn't yet work with the R4 segments, but I found that the R3 segments do seem to work ok after all, provided there's space for the excess buffered filament to protrude out the end of the buffer - which there is in my case.
With the R3 segments the loading fork works very nicely.
My loading points are done, and my updated spool holder STLs are about ready to upload to Printables.
I also tweaked the PTFE clips to make 2-tube and 3-tube versions. It's all fairly tidy now, and in my limited testing I've not had any problems with friction from these tube paths. I'm optimistic that it's going to work.
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Hey Chris,
this looks really interesting. I am currently waiting for my MMU3. I am looking forward to try out your buffer mount to the enclosure and combine it with the (un)official Prusa Drybox.
The Drybox will be mounted on top of the enclosure. To pass the PTFE tubes from the drybox into the buffer I will try out something like what is done here:
RE: MMU3 and Prusa Enclosure - how did you set it up?
That drybox looks like an excellent solution - they've done a nice job of matching the look of the enclosure. Are you planning to buy the printed parts or print them yourself? I'd be interested to know how many print hours are needed. I may give it a go myself.
I think I still need to tweak one of the buffer mounting feet a little, but then I do plan to upload them to Printables, and will post a link here.
RE: MM3 and Prusa Enclosure - how did you set it up?
I have bought the non-printable parts version from Aliexpress and currently printing all the parts. I have re-sliced the 3mf-files parts to use Input-Shaper. Approximate print-time is about 55 hours with Input-Shaper. Currently about 50% of the parts are printed and all worked flawlessly so far.
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Maybe it also works without a filament buffer.
I will use 5 individual drying boxes with an insert to prevent tangling. I don't know yet whether it will work.
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Are you not concerned about changing the length of the tubes to the buffer? I thought this was a huge issue with loading to the MMU unit according to Prusa and a lot of testing went into the setup to fix this issue to come up with the exact length that created the right amount of tension for the unit to be able to grab and load the filament.
I don't have an enclosure but I have a setup ready for when my MMU3 upgrade arrives, due to restricted space to place the spool holders.
Top 3 spool holders's PTFE tube length is about 700mm (vs 650mm that Prusa use) . The bottom 2 are about 600mm in length.
I'm hoping this won't be an issue for me.
RE: MM3 and Prusa Enclosure - how did you set it up?
Indeed an very interesting dry box; any recommendation on where to buy PTFE tubing fitting the dry box and MMU?
RE: MM3 and Prusa Enclosure - how did you set it up?
Still waiting for my kit to ship...
I currently have a SUNLU FilaDryer S1.... and adding in four more filaments with an MMU3 -- seriously considering the new SUNLU FilaDryer S4.... pretty outstanding... but what's the best way to meet requirements with the MMU3 + Enclosure + Filament dryer boxes? I look forward to your tube length experiments...