PLEASE help me resolve the constant "Filament Stuck" errors
Hi guys, nice to meet the community. Let me introduce myself for some background.This is my first Prusa Machine but I have been printing for a while now and have a small farm and know my way around printers - Not a custom Voron level but I can fix most issues on my printers.
I have had the Prusa XL Multitool for about a month, it costs about 4 months worth of salary where I live so I spent quite a lot expecting at least a decent experience from Prusa. So far I have been very, very dissapointed. 2 defective thermistors and 1 filament sensor cable out of the box (quality control I guess?) But those are minor compared to the constant filament stuck issues i keep having with it especially but not limited to multi color/multi material printing.I have to baby sit the printer and fix that every 1 to 5 layers depending on my luck. absolutely frustrating. At this point I can use 1 toolhead and just manualy change the filament myself.
I have printed those PTFE Guides to help the filament feed streight with 0 change when it comes to the issue, although it looks kinda cool in orange and black.
I contacted Chat support and they have been beyond useless. The lady I got assigned to was gaslighting me that I have to use the default Prusa filament settings for Input shaping profile because its "too fast" and the temperature there is 220 instead of my 215c. I tried to explain that although the speed seems high to her its really not that fast and I have set my filament profile to 7.5 Volumetric which is far less than the Default 15 so my speeds are actually lower and even if they were not a 5c difference in that speed range (around 100m/s on average) wont make any difference. She told me that "I need to do it or the troubleshooting can not continue" Well as you might have guessed I did it test with Default profile and other than the printer printing faster there were absolutely no change when it comes to the fillament stuck issue.
Please help me fix this issue!The printer is literally collecting dust at the moment and I am considering returning it because I cant stay and baby sit it while operating 12 other machines...
Best Answer by C3D:
I would like to update everyone on the issue as it seems I was able to resolve it.
Short answer is nozzles were overtightened from factory and dented the tube which icreased the pressure inside and blocked the easy passage of the fillament, which during tool changes had the extrudder skipping and triggered the safety or if disables ultimatelly clogged the heatbreak.
This was discovered during some testing with an actually helpful support employee. We were testing different things no easy on the feeding of the fillament at which point I had my toolhead#3 clogged which was the most problematic one so I wanted to unclog it to do the somewhat successful testing with that toolhead.
Once I took the nozzle out I saw this:
Currently printing successfully with properly tightened V6 adapters white waiting for the replacement nozzles.
The adapters dont work as well at least with my offbrand V6 nozzles, the printing quality is degraded substantially.
Hope this helps someone!
RE: PLEASE help me resolve the constant "Filament Stuck" errors
My experience with support was frustrating as well. A defective thermistor as well. I'm remote and parts take a long time getting here. I was having a lot of random problems and stuck filament happened a lot. I solved it with ferrites on the wires from both sides into the controller and on the controller up front as well as power supply. I think it is very sensitive to EMI and if you are around all those printers there's plenty of EMI. We never actually could find any stuck filament. It reminded me of a problem we were having with a big industrial CNC router in the past and solved it with ferrites. NO issues like that since until a thermistor died. I've got to say that compared to our experiences with our old MK3S+ printers the XL has been frustrating. When it's working it's fantastic. But the issues lead me to take it out of our production. Hoping once the thermistor arrives it behaves again and I can put it back to work. I can't waste weeks of time with it again. Chat support was such a pain I went to email with a 4 day lag and limited success with them. Prusa has a potentially great machine but they need to up their game with it.
RE:
Hey Eric, Thanks a lot for your reply and sharing your experience. From what I've tried so far it seems I get real stuck filament issues more often that just false positives. I am not sure if those are slight heatcreeps due to some firmware bugs/errors but when i tried disabling the option sometimes I would hear cracking sounds from the extruder (as is the case with stuck filament or clogs) and some skipped layers or air printing happens. Sometimes its permanent for the specific tool, sometimes it gets resovled on a the next or after some tool changes back to the specific head. It would actually have been nice if I could just disable the option, but sandly thats not the case for me. Not sure what to do in this case I might try reasembling the tools as some seems to have the issue more often than others and judging by the QA control of the rest of the printer I have serious doubt they were assembled flawlessly in production.
RE: PLEASE help me resolve the constant "Filament Stuck" errors
I bought the XL printer assembled and have been operating it with the original enclosure right from the start. The "filament stuck" problem started showing up after about a week. I'm only printing PLA so far, so I suspected the filament softening in the feeder due to the higher temperature. After opening both the cover and the harmonica, the problem subjectively improved a little. Even so, it will happen after about an hour at the latest.
Attention, it is not enough to insert the fiber again, but it must be removed and cut off approx. 10 cm of the visibly weakened fiber, otherwise it gets stuck in each layer again.It doesn't seem to matter the specific head or PLA manufacturer.It's very frustrating, but still better than printing "blank".
What do you advise?
RE: PLEASE help me resolve the constant "Filament Stuck" errors
Hey Radek, thanks for contributing.
My printer is not enclosed and is actualy in a colder enviroment due to proximity to the air conditioner.
While not printing in the air is cool and all, having to trim the filament and watch the printer constantly while its working is more than unacceptable for a 4k euro machine in my personal opinion.
I have tried a bunch of things including adding spool holders with bearing to ease on the extruder pull strenthgs, tightening the extruder, loosing the extruder, downgrading to firmware 6.0.1. Nothing seems to work. If I disable the sensor it keeps printing but sometimes I will see gaps in the print or whole colors being skipped due to real filament suck. The holes are probably caused by the filament not extruding until the extruder can grab it.
The issue seems to happen 99% during tool changes when the tool is starting to extrude on the wipe tower.
I will be contacting support again with all my finding and if they cant provide a plausable solution I will seriously think about returning it sadly.
RE:
Sensing the internal tension in the extruder as a prevention of nozzle clogging is, in my opinion, a great innovation. But it must not bother the user. The printer should take care of this on its own. For example, by heating the nozzle to a higher temperature and extruding a larger amount of fiber in front of the pad. Try suggesting it to support.
Important for you: "Filament Stuck" is detected by increased internal pressure in the extruder = the problem and the solution therefore lie between the feed wheel and the nozzle. Conversely, the printer cannot detect a jammed spool. Feel free to try it by holding the filament. Bearings on the spool will not solve the problem.
RE: PLEASE help me resolve the constant "Filament Stuck" errors
I would like to update everyone on the issue as it seems I was able to resolve it.
Short answer is nozzles were overtightened from factory and dented the tube which icreased the pressure inside and blocked the easy passage of the fillament, which during tool changes had the extrudder skipping and triggered the safety or if disables ultimatelly clogged the heatbreak.
This was discovered during some testing with an actually helpful support employee. We were testing different things no easy on the feeding of the fillament at which point I had my toolhead#3 clogged which was the most problematic one so I wanted to unclog it to do the somewhat successful testing with that toolhead.
Once I took the nozzle out I saw this:
Currently printing successfully with properly tightened V6 adapters white waiting for the replacement nozzles.
The adapters dont work as well at least with my offbrand V6 nozzles, the printing quality is degraded substantially.
Hope this helps someone!