Extruder clicking, unable to print anything, filament loading and unloading OK
Hi,
Last night while printing, my filament spool got jammed. Now, the extruder is making clicking noises and is only able to extrude a tiny,tiny bit of filament. I can load and unload filament OK but it won't purge anything. I heated the nozzle to 200C and stuck the wire up the nozzle hole -- it will go fairly high up inside there. I also performed a complete diagnostic self-check and a gear calibration to no avail. I suspect there is some filament stuck inside the extruder but I am not sure what to do. How can I get the printer working again?
Many thanks always -- Paul
RE: Extruder clicking, unable to print anything, filament loading and unloading OK
Hello again,
I've tried the cold pull, it seems the filament that's loaded in isn't even making it down to be melted...I'm not quite sure what to do.
RE: Extruder clicking, unable to print anything, filament loading and unloading OK
It seems that at the bottom side of the PTFE tube, a little piece of filament is stuck.
- If you want it out upwards, you have to disassemble the extruder 🙁 Is a lot of work, but possible)
- If you want it out downwards, it has to melted out. No disassembling needed, only some time and patience.
I would do it like this (but there may be others around the forum with much better options):
- go to settings, set the nozzle temp to > 200 degrees, so you are sure it is melting in the nozzle and heater block.
- loosen the idler screws (I don't know exactly how this works on the MK4) in such a way that you push/pull the filament in-out (like on the cold-pull).
- gently push the NEW filament in, very gently. You cannot force this.
- (If it is as I think ?-). then the old filament will melt, and run out of the nozzle slowly. Keep gently pushing until the you feel the filament going down.
- assemble as normal and run again.
We will do what we have always done. We will find hope in the impossible.
RE: Extruder clicking, unable to print anything, filament loading and unloading OK
Nothing seems to work. I kept the temp at 270C for a half hour, pushing filament through, and trying to clean out with a 2cm long wire in the nozzle. When I reload filament it takes it in a bit, then stops. No purging happens.
This is a brand-new printer, first time I changed filaments after loading the original Prusa reel. Somebody on another forum said I might need to order a new nozzle. What a drag!
If anybody has ideas, I'm happy to try! Thank you all very much --
RE: Extruder clicking, unable to print anything, filament loading and unloading OK
RE: Extruder clicking, unable to print anything, filament loading and unloading OK
Let's think this through a bit (I'm also only a few months into a new MK4 and 3D printing in general...) - the extruder is split into the hot end which melts the plastic, and the upper part of the nextruder which is cooled by the hot end fan to prevent plastic from melting on its way to the hot end nozzle. But, you seem to have melted plastic in the upper part.
This happened to me when I had a clog partway through a print. I too tried what you did. In the end, what eventually worked was using one of the nozzle cleaning tools that Prusa provides - like your pin but more like 40 mm long. I was able to un-stick the plastic in the upper part, which allowed me to push it down through the hot end again when it was hot. Then I did some cold pulls until they came out clean.
Prusa MK4 since Jan 2024, Printables: @MikeB_1505898
RE: Extruder clicking, unable to print anything, filament loading and unloading OK
Thank you so much Mike! I'm going to have a friend over next week to help troubleshoot -- he has an MK3. I don't seem to have a 40mm nozzle cleaning pin, I ordered the five-pack from Prusa (along with a replacement nozzle, just in case). Fortunately my university has a Bambu printer I can use in the meantime! If you have any other ideas please let me know !
RE: Extruder clicking, unable to print anything, filament loading and unloading OK
I don't seem to have a 40mm nozzle cleaning pin,
Take the nozzle off, this will give better access, and the cleaning tool you have, may be long enough.
We will do what we have always done. We will find hope in the impossible.
RE: Extruder clicking, unable to print anything, filament loading and unloading OK
Thank you all -- the printer is working again! I got the broken filament out and everything is back to normal. Very grateful for all your thoughts & advice!