Extruder Jamming Issue  

Re: Extruder Jamming Issue

Update: I seem to have fixed the issue for now. My suspicion was that my heat break was getting too hot so I removed the enclosure around my printer to lower the ambient temperature. That helped a bit, but what really fixed my problem was disassembling the hotend a second time and thoroughly cleaning off the old dried heat sink compound from the heat break and fins and coating the parts with new compound. It appears that the heat sink compound does not have an infinite lifespan and needs to be re applied periodically when printing at high temperatures like I do on occasion.

Re: Extruder Jamming Issue

I'm having this same issue, did it reoccur after you think you solved it? Just curious if your fix ended up being permanent?

Re: Extruder Jamming Issue

Update: I seem to have fixed the issue for now. My suspicion was that my heat break was getting too hot so I removed the enclosure around my printer to lower the ambient temperature. That helped a bit, but what really fixed my problem was disassembling the hotend a second time and thoroughly cleaning off the old dried heat sink compound from the heat break and fins and coating the parts with new compound. It appears that the heat sink compound does not have an infinite lifespan and needs to be re applied periodically when printing at high temperatures like I do on occasion.

Consider using a more stable thermal compound like Thermal Grizzly Kryonaut (preferred) or Arctic Sliver 5.

RE: Extruder Jamming Issue

Posted by: reid.w

Hello, my Prusa Mk2s upgraded to Mk2.5 is exhibiting some strange extruder problems that I cannot resolve despite my best efforts. What happens is a print will start off great and then anywhere between 1-30 minutes after starting the print the extruder will gradually jam and stop extruding. After stopping the print and restarting without touching anything, it will start extruding fine again and then jam up like before. Sometimes it goes a few layers before jamming but most of the time it jams on the first layer. 

I'm using a brand new roll of Prusament with stock components plus a heater block sock. 0.2mm first layer using stock Slic3r PE 0.1mm profile with prusament selected.
Here is what I have tried without success:

-Increased temp up to 245C and decreased temp as low as 190C
-Adjusted Z height both up and down. Layer height for areas that print correctly looks perfect at current setting.
-Increased and decreased extruder gear tensioner. Too lose the filament grinds when it stops printing. Too tight the extruder skips steps when it stops
printing. Tension has no apparent effect on how long the print goes for before jamming.
-Reduced friction in spool holder using bearings.
- Adjusted print speed up to 150% and as far down as 50%. Going faster seems to allow print to get further along before jamming.
-Disassembled and cleaned heat block, heat break, and replaced nozzle. There was a glob of plastic between the heater block and the cooling fins but I
removed it and it made no improvement. Everything else looks fine.
-Lubricated bondtech gears with molybdenum grease.
-Increased extruder stepper current to 750mA.

I'm out of things to try so I'm welcome to any ideas. It sounds like a thermal issue but I don't know what it could be. 😐

Thank you for your help
-Reid

I am having the same issue. Help is appreciated.

Thanks in advance,
Regards,

Shane