Re: 2nd Filament fails to reach extruder after bowden length calibration
Question: Is there a button combination to 'save' the calibration? Or is it saved when you hit the middle button to retract the filament after setting the length?
The centre button retract the filament and stores the calibration.
However, please note that when calibrating and using the up/down buttons, the last movement before saving should be down, due to the backlash in the system. Basically, if you need to raise the filament position, raise it too much and then bring it back down.
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: 2nd Filament fails to reach extruder after bowden length calibration
I have contacted the support for the second time, and they finally sent me new gears of better quality. They were aware of poor quality ones. I didn't tested them yet, but roughly measured them and they are all +/- 6.3 mm.
The faulty ones are on the right side. Notice their round cylinder's edges and silver bolts. The precious ones are on the left side with sharp cylinder's edges and black bolts.
Re: 2nd Filament fails to reach extruder after bowden length calibration
Mine varied a fair amount, and looked like your first set. I didn't love the set-screws either, I'm sure after moving them twice they are mostly destroyed.
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Re: 2nd Filament fails to reach extruder after bowden length calibration
Mine varied a fair amount, and looked like your first set. I didn't love the set-screws either, I'm sure after moving them twice they are mostly destroyed.
at least they didn't use something dumb like a T2 or T3 setscrew. trust me small hex set screws work better, just gotta be careful
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Re: 2nd Filament fails to reach extruder after bowden length calibration
What's so bad about TORQs or torx or whatever it is. I find them to be hard to strip, at least in reasonable sizes.
The new firmware is great - even when it has issues, it handles it better and you don't end up with skipped lines (performs a filament swap after a fail)
I maintain an informal list of San Diego, CA 3D printing enthusiasts. PM me for details. If you include a contact email and I can add you to the informal mailing list.
Re: 2nd Filament fails to reach extruder after bowden length calibration
What's so bad about TORQs or torx or whatever it is. I find them to be hard to strip, at least in reasonable sizes.
The new firmware is great - even when it has issues, it handles it better and you don't end up with skipped lines (performs a filament swap after a fail)
I maintain an informal list of San Diego, CA 3D printing enthusiasts. PM me for details. If you include a contact email and I can add you to the informal mailing list.
Re: 2nd Filament fails to reach extruder after bowden length calibration
"reasonable size" torx works fine, once some jackass engineer makes them too small. it's a pain in the butt, and youll just go back to hex for very small setscrews
I have a Prusa,therefore I research.
Re: 2nd Filament fails to reach extruder after bowden length calibration
Do you know when will be ready to flash the new firmware? I've also the same problem of filament load, today prusa support sent me a new set of gears.
Re: 2nd Filament fails to reach extruder after bowden length calibration
Do you know when will be ready to flash the new firmware? I've also the same problem of filament load, today prusa support sent me a new set of gears.
The new gears will set you right up. Got mine replaced and I am a happy camper (=
Re: 2nd Filament fails to reach extruder after bowden length calibration
I've reordered the gears and got further but still had some problems. I thought I'd put it on hold and get things set up more orderly while waiting for replies to this thread.
I found this spool holder update on thingiverse. https://www.thingiverse.com/thing:3094325 . I decided to adapt it to use with a closed container to control moisture. My version of this thing to use with a closed box to control moisture is https://www.thingiverse.com/thing:3144013 .
After changing to the new setup, all the feeds work. It does sound like it over drives in some positions. I assume the software update that allows for individual calibration will fix that.
To me this indicates that at least some of my problems had to do with the spool holder and position of the Bowden Tubes
Re: 2nd Filament fails to reach extruder after bowden length calibration
The #28 firmware from Git appears to be working much better for me. I managed to print a tiny checkerboard pattern in black/white using the first two filaments. Right now I'm watching the sheep print and that seems to be going great so far. There is a LOT of slop in the filament length tuning, so the advice to make the final adjustment downwards is right on point.
Thanks to those in this thread, especially for the Arduino instructions!
Hopefully we can get an official (3.4.2?) firmware version with the individual bowden tube calibrations.
As a recap, my process for getting up and running:
- Removing and measuring the rollers. Mine were very consistent, but still put the smallest one in position 1.
- Flashed the #28 firmware from Git using Arduino 1.8.7 IDE for Leonardo board.
- Calibrated the bowden tubes for #1 and #2 filament position, making sure to move downwards to the calibration position, not upwards.
- Cleaned up the end of the filament, no stringing or 'bulb'.
So far, the sheep is doing well. Fingers crossed!
Re: 2nd Filament fails to reach extruder after bowden length calibration
wish you the BAAaast <---sheep joke
I have a Prusa,therefore I research.
Re: 2nd Filament fails to reach extruder after bowden length calibration
Sheep printed ok, but I need to up the purge volume from 70 to about 200. White layers where there is black on the same layer resulted in grey wool!
Re: 2nd Filament fails to reach extruder after bowden length calibration
Sheep printed ok, but I need to up the purge volume from 70 to about 200. White layers where there is black on the same layer resulted in grey wool!
I had the same. I went the the 'advanced' table and had to increase black->white to about 200, but could decrease white->black from 140 to 70 or so. I think it evened out in the end.
Re: 2nd Filament fails to reach extruder after bowden length calibration
Contacted support and they originally said I had problematic batch of gear wheels (with silver screws) but they said they will not be sending me replacements for the gear wheels, given that the new drivers will be released soon.
Re: 2nd Filament fails to reach extruder after bowden length calibration
Contacted support and they originally said I had problematic batch of gear wheels (with silver screws) but they said they will not be sending me replacements for the gear wheels, given that the new drivers will be released soon.
The new firmware has been released along with instructions. It works great.
https://shop.prusa3d.com/forum/general-discussion-announcements-and-releases-f53/firmware-1-0-1-for-the-mmu2-unit-t25148.html#p111453
Re: 2nd Filament fails to reach extruder after bowden length calibration
With these extruders so much different, it makes me wonder about the main extruder of the MK3. f
I see it correctly a difference would result in over or under extruding compared to "another" MK3.
Have people witnessed this and compensated for this, or is the default MK3 extruder better confirming to its spec?
Can this be verified with a test print? Is it worth checking?
Re: 2nd Filament fails to reach extruder after bowden length calibration
You could check it with a ruler! 🙂
I have the feeling those gears are better, but it's based on nothing but wishes. I think I've heard of people having off-center gears in there. Certainly giving them a good looking over would be beneficial.
I maintain an informal list of San Diego, CA 3D printing enthusiasts. PM me for details. If you include a contact email and I can add you to the informal mailing list.
Re: 2nd Filament fails to reach extruder after bowden length calibration
The issue I keep having with the individual filament calibration is that the filament doesn't feed / retract the same length consistently.
For example, I press the feed button and adjust the filament so it rests on the gear according to the guide. I retract the filament and feed it again to verify and find that it either feeds too much or not enough. I adjust again so that the filament sits on the gear according to the guide, retract, and feed again to the same issues. Rinse and repeat for all 5 filaments.
Sometimes the MMU will seem like everything is calibrated but every print fails by either having multiple missed layers or the filament grinds in the hobbed gear because it's pushing too much filament.
Re: 2nd Filament fails to reach extruder after bowden length calibration
Having the same issue.
Not managed a single print yet