Extruder pulley eating into filament
Hi there,
I've had my printer for a few months now, running intermittently as other things take priority.
A few weeks ago, the spool of PLA filament I was using got tangled when printing, and the print continued until the end (a few more hours) without being able to pull the plastic through.
Ever since this, the filament has stopped extruding partway through a print. The motor keeps trying to turn, and when I've pulled the filament out of the hot-end to check it after it fails, it's had a part eaten out of it by the pulley. I've tried cleaning out the gear's teeth, but that hasn't helped.
The tip of the filament (that's been in the hot-end) has a 'shell', not fully enclosed, rather than being solid as you'd expect. After that, there's a slightly thicker part before it goes back to normal. I haven't seen it do this before, and don't know what the issue is.
I've looked at the Trouble Shooting guide: the tension is at 14mm, the spool is (now) free to turn, the pulley is clean and not worn, the fan is running, the temperature is fine as it's one of the standard prints from the SD card, and the pulley screw is tight. I don't have calipers and can't measure the diameter.
Thanks for any help, and sorry for the blurry photos. My phone camera sucks.
Re: Extruder pulley eating into filament
Hi Tom,
have you sorted the filament tangle yet? it can be very annoying and if not sorted, can reoccur later, when you're not watching!
Have you tried printing one of the pre sliced models, if the pre sliced models work, the problem could be down to settings in the slicer configuration or something else.
small steps will help us help you,
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: Extruder pulley eating into filament
Thanks Joan,
I have sorted out the tangle: I had to cut out a couple of metres from the spool to fix it.
As for what I'm printing, I've been testing with the pre-sliced models, and the issues still occur using those g-codes.
Re: Extruder pulley eating into filament
Just to clarify, the issue is still persisting. I'm going to try and do some more cold pulls, and will post the results.
Re: Extruder pulley eating into filament
It looks to me like the tension on the springs is too tight. The hob gear should not cut into the filament that much.
Try loosening the tension till it just engages the spring.
Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage or loss. If you solve your problem, please post the solution…
Re: Extruder pulley eating into filament
I loosened the tension from 14mm (as recommended in the troubleshooting post) to 20mm.
The printer managed to get through 6 hours of printing without any issues, and completed the gear bearing from the SD card. It came out perfectly well, but the top is full of holes, leading me to believe that there's a blockage or something in the extruder stopping it from extruding at higher tensions and at this point.
I'm going to try some more cold pulls (I didn't actually try any as I said I would in my last post) and see if that helps, but let me know what you think after looking at it yourself:
Thanks again!
Re: Extruder pulley eating into filament
I loosened the tension from 14mm (as recommended in the troubleshooting post) to 20mm.
The printer managed to get through 6 hours of printing without any issues, and completed the gear bearing from the SD card. It came out perfectly well, but the top is full of holes, leading me to believe that there's a blockage or something in the extruder stopping it from extruding at higher tensions and at this point.
I'm going to try some more cold pulls (I didn't actually try any as I said I would in my last post) and see if that helps, but let me know what you think after looking at it yourself:
Thanks again!
Something is strange with your setup. At 20mm my screws would have fallen out! Can you show a photo of how you are measuring?
That photo is definitely showing under extrusion at the top layer. That trouble shooting post shows common causes. Blockage is one, filament spool not free to move is one, hob gear not connected properly is one. etc.
Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage or loss. If you solve your problem, please post the solution…
Re: Extruder pulley eating into filament
I loosened the tension from 14mm (as recommended in the troubleshooting post) to 20mm.
The printer managed to get through 6 hours of printing without any issues, and completed the gear bearing from the SD card. It came out perfectly well, but the top is full of holes, leading me to believe that there's a blockage or something in the extruder stopping it from extruding at higher tensions and at this point.
I'm going to try some more cold pulls (I didn't actually try any as I said I would in my last post) and see if that helps, but let me know what you think after looking at it yourself:
Thanks again!
Something is strange with your setup. At 20mm my screws would have fallen out! Can you show a photo of how you are measuring?
That photo is definitely showing under extrusion at the top layer. That trouble shooting post shows common causes. Blockage is one, filament spool not free to move is one, hob gear not connected properly is one. etc.
I may have made a mistake with my measuring - it was actually 15mm, not 20mm. Not sure how I made that mistake. This is how I do it:
It's a little blurry, but it's just using a ruler to measure the distance from the orange part to the washer at the opposite end of the spring.
When I took the tension screws out, I saw that the pulley had eaten in the filament again, which explains by there's all the holes in the top - it lasted right to the end before it started happening. There's also been all this dust from the filament in the cavity when I cleaned out before doing some more pulls:
I'm printing the gear again, this time optimistic about the quality. I think these pulls actually got rid of a blockage.
Will update later today.
Re: Extruder pulley eating into filament
The extra cold pulls worked - I've finished the print with no imperfections. Thanks for the help!