MMU2 Doesn't Load/Prime Correctly
I've just installed the MMU 2.0 upgrade on my MK3, and I've sliced a multicolor file in Slic3r. It kind of works, but the printer doesn't load and prime the extruder properly. The first layer's filament only starts coming out about a minute after the extruder starts moving around the print bed, so half of the first layer is just missing.
The same thing also happens when I run first layer calibration, it seems to push filament through the extruder just fine, but doesn't fully load and prime, so nothing is actually printed.
Any ideas what I might be missing?
Re: MMU2 Doesn't Load/Prime Correctly
did you do the semi secret PTFE tube length calibration?
I have a Prusa,therefore I research.
Re: MMU2 Doesn't Load/Prime Correctly
Have you tried printing one of the pre-sliced files?
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: MMU2 Doesn't Load/Prime Correctly
did you do the semi secret PTFE tube length calibration?
Nope, hadn't yet done it, I just assumed that if this was the problem, there wouldn't be any extrusion at all. Turns out I was wrong. After calibrating the tube length, it now prints perfectly. Thanks for the hint!
Re: MMU2 Doesn't Load/Prime Correctly
Have you tried printing one of the pre-sliced files?
Ah, I didn't realize there were pre-sliced files for MMU2. Next time I have an issue, I'll print them first to ensure slicing isn't the problem. Thanks for the pointer!
Re: MMU2 Doesn't Load/Prime Correctly
after rechecking all filament paths, bearings all move freely, gear aligned on the MMU2.0, also switched different filaments around, I get correct function from filament 1, but it fails at the rest of the filament lanes, it falls short at the extrusion bond-tech gear. I get no errors it just makes a mess at the wipe tower since there are missing layers during the color change? can lanes 2-5 be configured as well using the PTFE adjustment? I know it sounds weird since 1 work and the rest don't.
edit /
checked for any stringing none found, no grinding on any gear from extrusion to MMU2.0. also checked the position of the f.i.n.d.a. probe.
Re: MMU2 Doesn't Load/Prime Correctly
can lanes 2-5 be configured as well using the PTFE adjustment?
Not at the moment (that is coming soon). Can you measure the diameter of all 5 drive pulleys to see if they are about the same (6.32mm diameter is about correct). If they are all OK, then there could be other things you need to check out.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: MMU2 Doesn't Load/Prime Correctly
can lanes 2-5 be configured as well using the PTFE adjustment?
Not at the moment (that is coming soon). Can you measure the diameter of all 5 drive pulleys to see if they are about the same (6.32mm diameter is about correct). If they are all OK, then there could be other things you need to check out.
Peter
Hi Peter,
I did some investigating and Found a pattern with my filament loading I Haven't completed a single successful print. But I also get what you suggested. the pulley gears have different diameters,
fila1 6.3mm
fila2 5.92mm
fila3 5.95mm
fila4 6.mm
fila5 6.3mm
not by much but I can switch them around since they are out to see if my issues change. I used the bender pre-made gcode and then downloaded the STL and followed the mmu slic3r and had 4 copies made with the starting filament being the difference 1-4. ran the gode twice for every 4 runs as a base of measurement I removed the end of the PTFE from the extruder and left it hanging and measured the filament load length from the end of that
the results on both runs yield same load distances.
filament 1 53.54mm 2x 53.54mm
filament 2 25.31mm 2x 25.30mm
filament 3 18mm 3x 18mm ( pre made gcode same results)
filament4 16.82mm 2x 16.80mm
unless there are hidden parameters for each tool change or load time or the gear pulley dimensions have something to do with it or other factors are at play here I'm all ears. haven't given up even spent 1.5 hrs in on a two-color print acting as an aid to push the filament 2 channel after loading so the print won't skip a layer, I have to add no jams, nor stringing were found
hope this info helps.
Re: MMU2 Doesn't Load/Prime Correctly
im shocked the gears have that big of a difference. they might have to make a calibration for each one
I have a Prusa,therefore I research.
Re: MMU2 Doesn't Load/Prime Correctly
im shocked the gears have that big of a difference. they might have to make a calibration for each one
Yes, that is in progress. Bigger differences have been found 🙁
For now, if you put the smallest one on E1 and calibrate the feed, all the others should over-feed and hopefully prevent problems.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: MMU2 Doesn't Load/Prime Correctly
I switch the smallest hobbed gear to E1 and re-calibrated and it is working MUCH better. Thanks guys!
Re: MMU2 Doesn't Load/Prime Correctly
maybe they can start a gear swap 😀 " ill trade you my 5.9 for your 6.3" 😀
I have a Prusa,therefore I research.
Re: MMU2 Doesn't Load/Prime Correctly
That did the trick. thanks Peter you nailed that one. testing a 14hr print with some "geared" for racing frogs. pun acepted 😀
Re: MMU2 Doesn't Load/Prime Correctly
did the outline get into your purge block? and why do I want to play battle toads for some reason now?
I have a Prusa,therefore I research.
Re: MMU2 Doesn't Load/Prime Correctly
Yes it did, still new to this mmu printing. Forgot to turn off the outline. Haha battle toads wow your outdating yourself.
Re: MMU2 Doesn't Load/Prime Correctly
at least im only dating myself to 1991.. 🙂 could have been worse.
I have a Prusa,therefore I research.
Re: MMU2 Doesn't Load/Prime Correctly
Hello Forum and Prusa Guys and greetings from Germany.
Since 3 days I have the MMUv2 assembled but was not able to finish any test print on it but after troubleshooting and (specially after I read this topic) I could manage to have 3 Filement lines working.
Unfortunately I can confirm also my pully gears are compleately different in the diameter.
Filament line 1 - 3 are working (after calibrating the bowden tube lengh) but when it comes to Filament line 4 and 5 the Filament does not reach the Extruder gear at all and the Printer magically print in the air...
Anyway I guess the best solution would be to have a calibration parameter for all 5 lines in FIrmware.
As I could not find it, does anybody know if there is something like a beta MMU2 Firmware available to test or is this still under development?
Thank you,
Cheers Christian
Re: MMU2 Doesn't Load/Prime Correctly
I hear new firmware is on the way.
I have a Prusa,therefore I research.
Re: MMU2 Doesn't Load/Prime Correctly
As I could not find it, does anybody know if there is something like a beta MMU2 Firmware available to test or is this still under development?
Unfortunately, no sign of a fix as yet; devs still working on it 🙁
I did offer to write the code myself, but was told that it should not take them too long...
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: MMU2 Doesn't Load/Prime Correctly
Okay, sounds good.
Thank you Guys for the update.
Would be cool to have it before the Weekend to have something to do on the Weekend 😀
Anyway I have 3 running Filament lines, this are 2 more than the Printer had before so will try to get some test MMU Prints done.
Cheers Christian