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[Solved] Should I just get a Palette?  

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jefferson.l2
(@jefferson-l2)
Active Member
Should I just get a Palette?

This unit sucks. There's no other way to put it. I've had my MK3S for a while. It printed beautifully, but I can't even get the MMU2S to load filament consistently. Been trying for hours. I can load it by hand (there's a point here about not being able to move the selector with the buttons or knob on the printer, but I'll save that for later), and the filament path is fine (i.e. not much resistance). The IR sensor is calibrated. It's when it actually goes to load a filament on its own that it all goes wrong. When I can actually get it to load through the MMU2S unit (which is a whole issue on its own), when it gets to the extruder, the extruder grinds away for a couple seconds then the filament retracts. Then it tries again, fails again and retracts. But THEN THE PRINTER JUST CARRIES ON LIKE IT HAS FILAMENT. What in the actual...?

 

Is this a finished product or a beta test? Thought I was buying a completed unit, but the firmware seems like they still have lots of missed issues here.

 

This whole thing seems like a half-assed attempt to compete with other multi-material solutions. I'm interested in ease and consistency (like the MK3S itself provides).

So, like I stated in the title, should I just get a Palette or is this thing actually worth troubleshooting?

Posted : 03/08/2019 8:03 pm
jefferson.l2
(@jefferson-l2)
Active Member
Topic starter answered:
RE: Should I just get a Palette?

Addendum:

 

I can load filament by hand into the extruder if I take out the festo on the extruder and use the "Move Axis" option to manually feed. So it's not that the extruder idler is way too loose or tight. Not sure why it's having trouble doing it by itself.

Posted : 03/08/2019 8:05 pm
gnat
 gnat
(@gnat)
Noble Member
RE: Should I just get a Palette?

You say the IR sensor is calibrated, but all the symptoms you mention are usually caused by either the IR sensor (the loading issues at the extruder) or the FINDA (loading issues at the MMU and selector not wanting to move).

As far as your specific question, YMMV. Plenty of us have gotten our MMUs to play nice and are happy with them, but some have not and given up. If you research the Palette you'll find that it is not without issues and complaints either.

The community is here to help if you want to try to stick with the MMU.

MMU tips and troubleshooting
Posted : 03/08/2019 11:04 pm
jefferson.l2
(@jefferson-l2)
Active Member
Topic starter answered:
RE: Should I just get a Palette?

Thanks for your response. Took a break from it for a bit, and came back.

Had to remove the blade, which had already halfway removed itself, adjusted the gear for filament #2, loosened the idler carriage, and finally got it to load after trying many more times and many more resets. I still don't know what was causing it to grind in the extruder previously but oh well. Got the 2-color sheep to print and it did surprisingly well, though the gray didn't purge so well in the upper portion. You can kinda see the transition in the picture but it's more obvious in person.

Posted : 03/08/2019 11:55 pm
Nikolai
(@nikolai)
Noble Member
RE: Should I just get a Palette?

Hello jefferson,

First of all this is a forum from user to user. From time to time there is a response from officials but it's more an exceptions. Means any rants will not bring you closer to the solution of your issues.

I'm using MK3s+MMU2s more or less completely stock (different filament buffer). And I can tell you, it can work reliable. But for this you need to calibrate everything spot on. Based on your description I would also go for not correct functioning IR sensor. Things to check:

  • Filament path is perfectly set
  • Display the IR sensor status in the menu. Touch the sensor, move the top portion of the extruder, push the screw of the idler door. The value should only change if the door moved significantly and it should release if you move back.

If you get changing values by touching/moving anything at the top or if it's not changing at all if you push the screw, then the sensor is not correct calibrated.

We are here to help. Any information or tests you are doing is helpful to provide you with better hints.

Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram

Posted : 04/08/2019 12:45 am
ntdesign
(@ntdesign)
Reputable Member
RE: Should I just get a Palette?

Took me several months to fix mine, so you're definitely ahead of the game already 🙂

That said, look into the typical upgrades people are doing. I think some of them are really necessary, especially if you have problems with the filament path in the MMU unit. I obviously have no long-term experience yet, but since I finally identified my problem two weeks ago I accumulated about 200 hours in MMU prints with not a single load error (even using some dodgy filaments)! 

Posted : 05/08/2019 7:27 am
MartijnValkier
(@martijnvalkier)
Active Member
RE: Should I just get a Palette?

I think not, I received my MMU2S just this friday and got it up and running sunday after noon. Took a lot of time, effort, sweat and cursing but it's running like it is supposed to do. I did a lot of tinkering because of unloading failures, filament tip stringing (IOP PLA) and other weird sh.t. I tried numerous fixes, ramming speed, ramming time and so forth. I even did a few trial runs with the skinnydip python script, all to no avail. The skinnydip python script made things worse as the tips got lumpier, that didn't help much, loading the filament became impossible because it didn't fit the teflon tube in te extruder. Until I read something on the forum, I can't seem to find it at this moment, which had something to do with to cooling zone. That fix in combination with some minor tweaks did the job. See attached photos for more info about these settings. I think (youtube user) 0Calvin posted this tweaks. Lowering the extrusion temp helped as well (215 deg. 1st layer, 205 deg. other layers).

I only tested this with IOP PLA filament as PETG wasn't so much of a problem. As for now this setup works <whispering> flawless </whispering>.

This post was modified 5 years ago 2 times by MartijnValkier
Posted : 05/08/2019 3:22 pm
jefferson.l2
(@jefferson-l2)
Active Member
Topic starter answered:
RE: Should I just get a Palette?

Thank y'all for your responses. And thank you for taking the time despite my initial... shall we say, negativity? I appreciate y'all reading through the rant and still being helpful. The initial install and calibration process was definitely a bit frustrating!

Turns out that I had my idler carriage cranked way too tight. And I think the loading/unloading issues were because I had the extruder assembly too loose (I had loosened it while calibrating the IR sensor and didn't re-tighten it sufficiently). The IR sensor and filament path were good, but the extruder gear wasn't grabbing hard enough to consistently be able to load. I noticed this part when a few hours into a several hour multi-color print, the extruder was grinding a bit every few seconds. I think my extruder is running hotter than it used to (though not sure because it's been a while since I printed before the MMU) and the filament is getting a bit soft, but it's still printing [PLA] okay. Fortunately, I caught it in time to tighten the extruder down and let it continue on its merry way.

As for upgrades, I'm currently printing an auto-rewind spool holder because I really, really do not like the buffer. The buffer itself is fine and functional, but loading and unloading it really is not fun or efficient.

That being said, it does worry me about how hot the E-stepper is getting, once I move on from PLA and put this thing in an enclosure that the gear will just get too hot and start melting filament before it gets to the hotend. I saw some posts on GitHub about this. Do y'all have any experience with this or run into any issues like this running it in an enclosure?

Posted : 05/08/2019 4:21 pm
gnat
 gnat
(@gnat)
Noble Member
RE: Should I just get a Palette?
Posted by: jefferson.l2

The initial install and calibration process was definitely a bit frustrating!

It is for most of us, so you are in good company. Wait until you change something and have to go through the pain all over again (rebuilt my extruder and now the IR sensor is unhappy again) ☹ 

As for upgrades, I'm currently printing an auto-rewind spool holder because I really, really do not like the buffer. The buffer itself is fine and functional, but loading and unloading it really is not fun or efficient.

You might look at https://www.thingiverse.com/thing:3545935 before giving up on the buffer. It lets you move all the filaments to one side so you don't have the back and forth issues. It also adds extra room for your fingers to get in there and reasonably work with the filament. Finally it serves it's stated purpose of making the movement in and out of the buffer easier by removing the constriction of the press fit setup.

That being said, it does worry me about how hot the E-stepper is getting, once I move on from PLA and put this thing in an enclosure that the gear will just get too hot and start melting filament before it gets to the hotend. I saw some posts on GitHub about this. Do y'all have any experience with this or run into any issues like this running it in an enclosure?

Sounds like your idler door might be too tight. I noticed that going from my MK3 to the MK3S upgrade when adding the MMU that I could no longer manually feed filament through the extruder with the steppers disabled. Similarly was having IR issues and the motor was getting significantly hotter (like couldn't touch it after a 20 minute print rather than just being uncomfortable after a 30 hour print). After replacing my idler door all 3 issues resolved themselves (until the rebuild this weekend).

MMU tips and troubleshooting
Posted : 05/08/2019 8:24 pm
jefferson.l2
(@jefferson-l2)
Active Member
Topic starter answered:
RE: Should I just get a Palette?

Holy cow! I mean, mine is hot, but I can still keep my fingertips on it for maybe 5-10 seconds. However, I think the idler door might also be a little tight still, so thanks for that tip! It's been working now for about the last 24 hours straight, done a couple hundred filament changes, but I'll try loosening it off until it has trouble grabbing the filament during the change, then tighten it back down a turn or turn and a half. The bolt heads are currently 1-2mm below flush, so I'm sure they could be a little looser.

And I'll give that redesigned buffer a look! I mostly picked the universal auto-rewinder because it was a pretty dual-color look (a good test for a new MMU install), and I also like the idea of print-in-place mechanisms like the slipping spring clutch.

 

Anyhow, thanks again for the help! I'm gonna mark this thread as "Solved" since this is technically a troubleshooting sub. But I can officially say that I'm sticking with the MMU2S, and it *is* worth troubleshooting (for now, at least! 😬  ) 

Posted : 06/08/2019 1:10 am
Peter L
(@peter-l)
Honorable Member
RE: Should I just get a Palette?
Posted by: jefferson.l2

So, like I stated in the title, should I just get a Palette or is this thing actually worth troubleshooting?

I own both an MMU2S and a Palette+.

The out-of-box experience with the Palette is definitely better. But over time I've found that the MMU2S is much more reliable. I'm at the point where even very large (4,000+ filament changes) generally work on my MMU2S, and my Palette is pretty much just taking up space as I haven't used it in months. I was never able to get the Palette to work reliably with more than 500 or so color changes in one model.

You're already familiar with the frustrations of the MMU2S so I don't need to repeat them. The Palette generally fails in one of two ways: it can get out of sync with the printer and leave a stripe of the wrong color in your print, and the filament splices can occasionally break which ruins the print. The first problem is something that's been improved with the Palette 2, but the second is probably inherent to the whole approach of filament splicing.

No matter the approach you use, multi-material is definitely varsity-level 3D printing. There is no simple, reliable, high-quality, plug-and-play solution out there.

 

Posted : 09/08/2019 8:47 pm
Der773 liked
jeffrey.d10
(@jeffrey-d10)
Active Member
RE: Should I just get a Palette?
Posted by: nils.t

 

That said, look into the typical upgrades people are doing. I think some of them are really necessary, especially if you have problems with the filament path in the MMU unit.

Is there a list of these somewhere?  I can't understand why my unit worked like a champion for the first 5 prints and now most of my issues are with the ptfe downtube to the extruder jamming....usually from stringing or swollen tips.  This tubing to the extruder is too narrow in my opinion.

Posted : 25/08/2019 3:24 pm
ntdesign
(@ntdesign)
Reputable Member
jeffrey.d10
(@jeffrey-d10)
Active Member
RE: Should I just get a Palette?
Posted by: nils.t

There was a thread about it recently:

https://forum.prusa3d.com/forum/original-prusa-i3-mmu2s-mmu2-user-mods-octoprint-enclosures-nozzles-.../so-my-mmu-2-0s-works-ok-but-not-great-been-looking-at-the-mods-anyone-have-a-definitive-list-of-mk3s-mmu-2-0s-mods/#post-158136

Thank you.  I did read that one before...duh.  But I ended up taking my buffer off completely with no change in my filament tips.  But I think I may be on to something as gnat talked about a spacer for the hot end push fitting that was not included in the kit.   So for the tubing...we are looking for capricorn xs 4mm ID  2mm OD? 

Posted : 26/08/2019 2:34 pm
prusanewuser
(@prusanewuser)
Prominent Member
RE: Should I just get a Palette?
Posted by: @peter-l22
Posted by: jefferson.l2

So, like I stated in the title, should I just get a Palette or is this thing actually worth troubleshooting?

I own both an MMU2S and a Palette+.

The out-of-box experience with the Palette is definitely better. But over time I've found that the MMU2S is much more reliable. I'm at the point where even very large (4,000+ filament changes) generally work on my MMU2S, and my Palette is pretty much just taking up space as I haven't used it in months. I was never able to get the Palette to work reliably with more than 500 or so color changes in one model.

You're already familiar with the frustrations of the MMU2S so I don't need to repeat them. The Palette generally fails in one of two ways: it can get out of sync with the printer and leave a stripe of the wrong color in your print, and the filament splices can occasionally break which ruins the print. The first problem is something that's been improved with the Palette 2, but the second is probably inherent to the whole approach of filament splicing.

No matter the approach you use, multi-material is definitely varsity-level 3D printing. There is no simple, reliable, high-quality, plug-and-play solution out there.

 

@peter-l22

I am considering the 2S, 2S Pro and MMU2S. In terms of speed and noise, which is faster and quieter? 

If it takes 10 hours for a job to complete using i3MK3S, after adding solvable materials as support, how much longer will it take for the Palette and MMU2S to complete?

 

Posted : 26/11/2020 9:10 pm
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