Prints randomly force a filament change mid-print
Recently my prints are randomly stopping and forcing a filament change. It does it at random times, but usually early in the print. Sometimes only once, sometimes multiple times. Is there a filament or extrusion issue that would cause this, or is a software issue? Anyone experiencing this problem?
RE: Prints randomly force a filament change mid-print
Recently my prints are randomly stopping and forcing a filament change. It does it at random times, but usually early in the print. Sometimes only once, sometimes multiple times. Is there a filament or extrusion issue that would cause this, or is a software issue? Anyone experiencing this problem?
Which printer and which slicer do you use? Filament changes normally only take place if they are triggered by the gcode file.
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: Prints randomly force a filament change mid-print
Keep looking and you will find a trend. Nothing is random. If it is random, look at your wiring.
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Chuck H
3D Printer Review Blog
RE: Prints randomly force a filament change mid-print
Dodgy filament detection sensors also cause this issue. If it detects no filament for a fraction of a second (problems with wiring, problems with switch etc) then it goes through the unload/load procedure.
I had it on my cr10s, the little microswitch it uses for runout detection stopped working reliably, I replaced it and no more problems.
Before I changed the extruder to a Bunny & Bear geared on on my Mk3 it also occasionally did it if the sensor wasn't cleaned out of filament dust. Since the update that isnt a problem.
RE: Prints randomly force a filament change mid-print
@neophyl
I have two minis and each has an issue with the filament sensor.
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Chuck H
3D Printer Review Blog
RE: Prints randomly force a filament change mid-print
@cwbullet
On my Mini the original Prusa sensor didn't work either, that means the signal was inverted and wanted to print only without filament. For this reason I built my own construction and inverted the sensor signal. It's funny, because the sensor works with other people. But what the heck, mine works now and is even equipped with a control LED.
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: Prints randomly force a filament change mid-print
@karl-herbert
Same issue here.
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Chuck H
3D Printer Review Blog
RE: Prints randomly force a filament change mid-print
Filament sensor. I've had this happen a few times. One way to check is to set filament sensor action in the settings menu to continue. If that ends the behavior you know where to look.
Here's the troubleshooting site:
https://help.prusa3d.com/en/article/ir-filament-sensor-troubleshooting-mk2-5s-mk3s_112226
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Prints randomly force a filament change mid-print
@fuchsr
Yes, the Prusa Mini Sensor is also a hybrid version. It switches the contact through when filament is inserted but the firmware interprets this as not present. To check the switching process I installed a LED. I changed the Mini firmware to invert the signal. After the firmware change the Mini now detects existing or leaking filament correctly.
Anyway, it runs now.
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: Prints randomly force a filament change mid-print
I had random filament changes, no gcode related.
Happened when extruder motor get hot while in enclosure. Added a bit of cooling there and voila! No random changes anymore.
So filament sensor is fooled when in too hot condition. MK3S as printer.
RE: Prints randomly force a filament change mid-print
I had random filament changes, no gcode related.
Happened when extruder motor get hot while in enclosure. Added a bit of cooling there and voila! No random changes anymore.
So filament sensor is fooled when in too hot condition. MK3S as printer.
I'm going to have to check this tomorrow as like this evening it printed for an hour before the first forced filament chance then the intervals were getting shorter and shorter. Heat makes sense. I'll try running it with the door open, and check the extruder gear tension.
RE: Prints randomly force a filament change mid-print
I was able to reprint the part with the door open on the enclosure. I did also back off the extruder tension to where the screw is 1 thread past the nut. I also re enabled the filament sensor.