Filament changing bug?
I have made three different, but similar prints with print time between 11+ and 12+ hours. Each of them got several filament changes after about 10 hours of printing time. I didn't count filament changes, but maybe the count was four or five. The print time between changes was only a few seconds.
I did save the last stl-file and check it for M600 filament change commands and I could not find any.
The software version was 5.0.1. which is now updated to 5.1.0
RE: Filament changing bug?
And where is your question? Maybe you can share the STL file for us to check.
RE: Filament changing bug?
This is one of the three stl-files where I get those filament change requests FlightStick-Stick Front 3_0.4n_0.15mm_PLA_MK4IS_12h23m
RE: Filament changing bug?
Ok so there are no colour changes in that gcode (its gcode and NOT a stl file btw). Fine but that doesn't help us track down your issue. Neither does a actual stl file on its own.
The only thing that can possibly be used is a copy of your Prusa Slicer project file. Basically slice it with your expected colour changes to the point where you can export the gcode (making sure there are no M600's in there as before but you think there should be) and then use File>Save Project As to save a PS 3mf file.
With a project we can see all your settings and the profiles as well as the model etc. Its a snapshot of your slice. So take the 3mf file and zip it and attach. Without it all you have are guesses.
RE: Filament changing bug?
Yes I did not have stl-files available because I use Prusa Link from the slicer and I didn't save the stl-file. Attached file was exported from the printer after the error. And my problem was that I did NOT have color changes, but the printer did several of those one after the other and each color was printed only a few seconds. The slicer changes color at layer change, but these changes was done inside the same layer.
RE: Filament changing bug?
Then that sounds more like a problem with the filament sensor. That will express itself as a request to change filament. Its not caused by any gcode but a physical problem with the printer. There are many cases for MK3 printers on the forum with that problem, the MK4 being newer then not so much yet
Usual thing to confirm would be to print with the filament sensor turned off and see if the random requests to change filament go away. Once the filament sensor is confirmed as the issue then its down to tweaking and adjusting that.
RE: Filament changing bug?
Now I have a bit different problem. The filament run out and printer request to remove filament. I did do that and printer continues to filament loading step. Then something go wrong. The the printer prompts ”Please remove filament from filament sensor.”. There is no filament and the menu-buttom doesn’t do anything but beeps. Only thing I could do here is the reset. I hoped that printer could continue the job but no. Next I did load the new filament without any troubles.
Because reset removed the error my opinion is that the filament detection problem is in the software.
What I did wrong? Why the printer did not continue the job?
Sometimes when you remove filament a fine string of filament remains on the end, but if this breaks the resulting scrap may still be triggering the sensor - or there may be dust clogging the sensor, usually it's just a matter of manual cleaning with a fine brush or a blower. Even a cobweb can jam a sensor if a printer is left for a while.
Cheerio,
RE: Filament changing bug?
I was aware of the filament remains and try to clean sensor. I did not use brush or blower, but I did open the extruder and use filament clip to sweep the sensor. I also use extra light to check the sensor. My opinion is that it was clean.
The error screen was odd. The small text "Please remove filament from filament sensor." was at top line, the middle of the screen was totally empty. The bottom line have some text and symbols. I remember that the symbol on right was "o|o".
Every screen should have some kind of UI (minimum 'Cancel' or 'OK')? Now there was nothing. The screen was dead end. The only exit was reset.
Everything was fine until I put new filament to extruder. Then SW jumped to this screen.
After the reset the printer boot up normally and it did not continue the print task!
Quite soon after that I did load new filament and now the sensor was clean.
My opinion is that this was a software bug and not a hardware problem.
RE: Filament changing bug?
Do we have fix for this error? My firmware version is 5.1.3.
Now I get this same error when I change filament. Again, "Unloading Filament" screen do not have exit! WHY? There is nothing in the filament sensor!
I must reset the printer (I did use power switch) and then Load Filament. The problem is solved.
I just wondering how reliable sensor would detect real filament run outs?
With an exit key I could manually load new filament without a reset or even better if sensor false detect problem could be fixed.
RE: Filament changing bug?
Next time a screen photo would be much helpful.
RE:
From the screen it is obvious, that the FS is ON, ie. it still detects (falsely?) the filament presence. Until the FS is ON, it will not allow you to continue. Focus your attention to FS function eventually recalibrate the FS. Incorrectly calibrated FS can also introduce some issues.
Try to play putting and removing the filament into the extruder and watch the reaction on the display. If you have set the load filament to auto, putting the filament in the printer should start the load filament process. I assume that you have set the the FS ON in settings menu.
RE: Filament changing bug?
I try to re-calibrate the sensor.
I am not checked if FS ON text changes between ON and OFF, but I doubt that because it is ON without filament.
When the sensor detects falsely that filament would not removed I put and remove filament several times but it does not help. After the reset the sensor detects and loads filament normally every time. It does not ask to remove (non existing) filament first. That is odd.
Does the printer boot adjust the filament sensor again?
RE: Filament changing bug?
I just had this happen when changing filament when it was approaching the end of the spool. Also could not get it to clear and move on, opening filament door/cleaning, nothing was there, all I could do was power cycle and abort the print. Then it would load fine, and was able to reprint.
The one thing I think may have triggered this: when I did the change filament step during the print, as soon as the filament was ejected I put the next one in right away without looking at the screen. I was thinking putting the next one in too quickly before it was ready put it into a bad state? Other times I've changed filament I would always go through things a step at a time, this time I was in a hurry and may have gone too quickly. Worth testing to see if you can reproduce it this way!
RE: Filament changing bug?
I just had this happen when changing filament when it was approaching the end of the spool. Also could not get it to clear and move on, opening filament door/cleaning, nothing was there, all I could do was power cycle and abort the print. Then it would load fine, and was able to reprint.
The one thing I think may have triggered this: when I did the change filament step during the print, as soon as the filament was ejected I put the next one in right away without looking at the screen. I was thinking putting the next one in too quickly before it was ready put it into a bad state? Other times I've changed filament I would always go through things a step at a time, this time I was in a hurry and may have gone too quickly. Worth testing to see if you can reproduce it this way!
The same thing happened to me, I didn't read the screen and got stuck at the screen. Now I got a small allen wrench in the top and it prompted me to insert the new filament. I continued the print like nothing happened.
RE: Filament changing bug?
Hi, Everyone! I have a work around for this. I can confirm that with the latest firmware as of 4/26/2024 this "Please remove filament from filament sensor." bug still exists. While in the middle of a print job, it occurs during an attempt to change the filament.
The work around: Use Power Panic! Give your machine a sudden power loss -- pull the power cord out of the power supply to simulate a power outage. Do not touch the power switch or the reset button, just pull the power cable. Give it 30 seconds or so (put new filament into the extruder, see next paragraph) and then put the cable back in with the power switch still in the on position -- just like a power outage ending.
For me, the printer recognized it had been in the middle of a print and continued from exactly where it had stopped. Now, it did not realize there was no filament in the extruder, so I pushed new filament into the extruder as the printer was starting to continue the print. It printed without any filament extruding for just a very short distance as the printer continued the interrupted print while the filament was loading. My best advice here is to put the new filament into the extruder while you have the power off so that it will begin loading as soon as possible after you plug it back in.
Hopefully, Prusa will find and fix this bug. Nobody wants to have to unplug their printer in the middle of a long print job. Good luck!
RE: Filament changing bug?
I just had this happen when changing filament when it was approaching the end of the spool. Also could not get it to clear and move on, opening filament door/cleaning, nothing was there, all I could do was power cycle and abort the print. Then it would load fine, and was able to reprint.
The one thing I think may have triggered this: when I did the change filament step during the print, as soon as the filament was ejected I put the next one in right away without looking at the screen. I was thinking putting the next one in too quickly before it was ready put it into a bad state? Other times I've changed filament I would always go through things a step at a time, this time I was in a hurry and may have gone too quickly. Worth testing to see if you can reproduce it this way!
The same thing happened to me, I didn't read the screen and got stuck at the screen. Now I got a small allen wrench in the top and it prompted me to insert the new filament. I continued the print like nothing happened.
I was also able to resolve the problem by using an allen wrench and putting in the top and twisted it around a bit and then got the prompt to add the new filament.
RE: Filament changing bug?
I got the same issue today (it happens about one in twenty color changes). The power cut tip from @kmaclucent works, unfortunately the print still failed since I have only three layers of the last colour. MK4 with latest firmware.
Hi, Everyone! I have a work around for this. I can confirm that with the latest firmware as of 4/26/2024 this "Please remove filament from filament sensor." bug still exists. While in the middle of a print job, it occurs during an attempt to change the filament.
The work around: Use Power Panic! Give your machine a sudden power loss -- pull the power cord out of the power supply to simulate a power outage. Do not touch the power switch or the reset button, just pull the power cable. Give it 30 seconds or so (put new filament into the extruder, see next paragraph) and then put the cable back in with the power switch still in the on position -- just like a power outage ending.
For me, the printer recognized it had been in the middle of a print and continued from exactly where it had stopped. Now, it did not realize there was no filament in the extruder, so I pushed new filament into the extruder as the printer was starting to continue the print. It printed without any filament extruding for just a very short distance as the printer continued the interrupted print while the filament was loading. My best advice here is to put the new filament into the extruder while you have the power off so that it will begin loading as soon as possible after you plug it back in.
Hopefully, Prusa will find and fix this bug. Nobody wants to have to unplug their printer in the middle of a long print job. Good luck!
-- Sent from Debian
RE: Filament changing bug?
Had this issue as well. I tried the allen wrench thing but it didn't work... However! I've keep a thin rubber flossing pick to clean the extruder gear (works pretty well), and using this to wipe the filament sensor worked! I was a little hesitant to scrub it with metal (AKA an allen wrench), but I went to town on that thing with rubber. After a few seconds, the printer was requesting new filament! Saved a long hour print and my sanity, thanks for the idea everyone.