Extruder clicking and jamming after nearly every good print  

Re: Extruder clicking and jamming after nearly every good print

Two things i would try:
- set your hotend temp to 220 degrees. wait until temp is reached, then select cooloff from the menu. start a stopwatch then until the hotend fan switches off there should be no more than 10-12 minutes.
- disassemble your hotend again, and see if you can push your teflon tube further into the hotend. If it's not completely inside, may be even a millimeter, then filament will clog this spot when cooling.
Or check inside the teflon tube for a possible damage, sharp cuttet filaments can scrape off some parts of the tube and this will clog the hotend.
-do a cold pull. remove the tension idler and warm up the hotend to 90 degrees with PLA, then jank out the filament by hand with some force, this cleans the nozzle. (google atomic pull or cold pull for further info)

Re: Extruder clicking and jamming after nearly every good print

I've tried atomic pulling, and they seemed to come out clean. I was hoping to be able to avoid taking apart the hot end, but I guess that's basically what it's been narrowed down to. I'll report back once I've tried your suggestion on the teflon tube, it could have rattled its way up a bit I suppose.

Re: Extruder clicking and jamming after nearly every good print

I've tried atomic pulling, and they seemed to come out clean. I was hoping to be able to avoid taking apart the hot end, but I guess that's basically what it's been narrowed down to.

This seems familar to me... After it "jams", and will no longer print (lots of clicky clicky action) extract that bit of filament, and measure it from the "molten end" to where the "bondtech gears stopped notching it".

Basically I wanna know "how deep" the jam happened in your hotend.
I just measured one of my old "jammed" bits, and it is ~66mm long. (from where the bondtech last "notched" the fialment , all the way into it, at the end.

I don't wanna jump to saying what was wrong with mine... I think it was a "fluke", but your symptoms seem EXACTLY like mine.

I could feed filament in, prime the nozzle, turn the printer off, come back in 30 minutes, and it is JAMMED TIGHT. As in, it will NOT print again.

Re: Extruder clicking and jamming after nearly every good print

I happened to clip the filament just at/above the gear notches before starting the previous print, and my calipers are measuring it at about 57~mm from where the teeth stop to the tip (slightly globbed) of the filament where it came out of the hot end upon doing an unload filament.

Re: Extruder clicking and jamming after nearly every good print

Hey, maybe it is related to the issue in this thread:
https://shop.prusa3d.com/forum/others-archive--f66/clicking-printhead-filament-stuck--t14916.html

Re: Extruder clicking and jamming after nearly every good print

I've tried atomic pulling, and they seemed to come out clean. I was hoping to be able to avoid taking apart the hot end, but I guess that's basically what it's been narrowed down to.

This seems familar to me... After it "jams", and will no longer print (lots of clicky clicky action) extract that bit of filament, and measure it from the "molten end" to where the "bondtech gears stopped notching it".

Basically I wanna know "how deep" the jam happened in your hotend.
I just measured one of my old "jammed" bits, and it is ~66mm long. (from where the bondtech last "notched" the fialment , all the way into it, at the end.

I don't wanna jump to saying what was wrong with mine... I think it was a "fluke", but your symptoms seem EXACTLY like mine.

I could feed filament in, prime the nozzle, turn the printer off, come back in 30 minutes, and it is JAMMED TIGHT. As in, it will NOT print again.

I just did a cold/atomic pull this morning after a print finished last night while i was asleep. The teeth marks were almost exactly 66mm long, and there was a bit of a collar or something wider than the filament after getting gear marks in it right where it transitioned from teeth marks to the atomic pull plug part of the filamnet.

Re: Extruder clicking and jamming after nearly every good print

Had that same exact issue with PLA. Turned up temp to 250 for like 5 minutes. Put needle through nozzle to clear it and then pushed PLA through it for a bit. Cleared it right up. Someone else had same exact issue on Facebook and they followed those steps and it cleared up for them. The high temp just clears everything right out and lets the filament begin feeding properly again.

Note: the raising temp to 250 was advice from Prusa on their Clogged Nozzle guide under "The filament is not pouring out of the nozzle ":

https://help.prusa3d.com/l/en/article/WWVRzOY1dX-clogged-nozzle

NOTE: Until I did the above, the clicking and non-feeding got worse and worse until I couldn't print anything. As soon as I did the above I've been back in business. 250c is silly high for PLA but works perfectly to clear it.

Re: Extruder clicking and jamming after nearly every good print

I just did a cold/atomic pull this morning after a print finished last night while i was asleep. The teeth marks were almost exactly 66mm long, and there was a bit of a collar or something wider than the filament after getting gear marks in it right where it transitioned from teeth marks to the atomic pull plug part of the filamnet.

You have a jam that's stopping the filament from getting through the nozzle so as it feeds in, it gets smooshed and forms that knob/collar at the end. Then it won't feed and becomes a pain to pull out. Try the 250c method.

Re: Extruder clicking and jamming after nearly every good print

I've tried atomic pulling, and they seemed to come out clean. I was hoping to be able to avoid taking apart the hot end, but I guess that's basically what it's been narrowed down to.

This seems familar to me... After it "jams", and will no longer print (lots of clicky clicky action) extract that bit of filament, and measure it from the "molten end" to where the "bondtech gears stopped notching it".

Basically I wanna know "how deep" the jam happened in your hotend.
I just measured one of my old "jammed" bits, and it is ~66mm long. (from where the bondtech last "notched" the fialment , all the way into it, at the end.

I don't wanna jump to saying what was wrong with mine... I think it was a "fluke", but your symptoms seem EXACTLY like mine.

I could feed filament in, prime the nozzle, turn the printer off, come back in 30 minutes, and it is JAMMED TIGHT. As in, it will NOT print again.

I just did a cold/atomic pull this morning after a print finished last night while i was asleep. The teeth marks were almost exactly 66mm long, and there was a bit of a collar or something wider than the filament after getting gear marks in it right where it transitioned from teeth marks to the atomic pull plug part of the filamnet.

🙁

This sounds EXACTLY like me.

If you line it up with your extruder, your 'collar' is at the 'neck' between the heatsink and the heat block?

If yes, I'm gonna give you some bad news.

Your heat break has failed. (Maybe defective to begin with?)

Order a "Micro Swiss Heat break

I find it higher quality than my E3D one, and it has been printing like a dream.

Check this thread.

https://shop.prusa3d.com/forum/hardware-firmware-and-software-help-f64/filament-jams-in-heatbreak--t15788.html

You may be able to get prusa to send you a new one. I didn't even try. Only like 2 people besides myself even said it could possibly be the heat break. Didn't feel like 'proving' what's wrong to prusa support.

Gonna try to get either prusa/E3D to autopsy it when they get home after ERRF2018.

PS: if you had a nozzle jam, why would your prints be fine?