I have a problem where after printing for 5-10 min. I hear a clicking noise coming from the filament/extruder and there is no filament coming out of the hotend, when looking closer it appears that the filament has gotten stuck inside the PTFE tube in the printhead and the noise is from the filament “springing” back when the stepper motor tries to push it down into the printhead.
Because this issue has already put me behind on a project in which i need the printer, I Decided to buy an etirely new extruder set (K8402), and has replaced the extruder motor and the right printhead.
This has unfortunately not solved the issue, but I now know it is not caused by:
A clogged or partially clogged nozzle.
The stepper motor being too weak - and the distance to the pulley on the motor is somewhere between 19,48 - 19,52mm.
I dont think it is the temp. Sensor, it displays the same correct room temp. As the other extruder, when the printer is not in use.
Even though i changed that too, I dont know if something is wrong with the small PTFE tube inside the hotend(see picture).
Up until this point, I have been printing many successful parts with the same roll of standard black PLA and there have been no problems with the material.
I print at 210 degrees with a 0,1mm layer height, and i havent changed any settings on the printer or in cura.
there is also sufficient slack in the filament spool.
I dont have any problems When trying to pull/push filament through the PTFE tubes manually - both the one in the printhead and the one connecting the extruder to the printhead.
Curiously, this all seemed to start when i installed an extra extruder on my K8400?
I have checked and the screw in the pulley on the motor and it is still tight and aligned correctly - on both the new motor and the one i replaced.
Dylan, I will try to lower the flow rate in Cura - just odd that I have been able to print many parts with the standard setting(think its 90) with no problems.
I have the exact same issue as you. First I thought it was the motor being to week and/or the fillament feeder getting stuck in the plastic piece surrounding it, but after some testing I realize it’s the plastic getting stuck in the print head somehow.
Should I take the print head apart and check if there is anything stuck in there? I was pretty accurate when measuring and cutting the tube in the print head.
I still havent managed to do a decent print after a week of extensive testing. Frustrating.
[quote=“Azidus”]I have a problem where after printing for 5-10 min. I hear a clicking noise coming from the filament/extruder and there is no filament coming out of the hotend, when looking closer it appears that the filament has gotten stuck inside the PTFE tube in the printhead and the noise is from the filament “springing” back when the stepper motor tries to push it down into the printhead.[/quote]How do you know the nozzle simply hasn’t got blocked? Are the blockages coming after the print head starts to increase in speed? If so, you might find that you need to increase the flow rate (think it’s set at 80 by default). Or do the blockages occur after printing fine detail? This might be down to several factors you could try, but my guess is that you’re printing hotter than you need to. As a result, you might want to increase the length / speed of retraction. I print black Velleman’s PLA @ 190C, FR 75%, 150mm @5mm retraction if it helps.
Did you solve this problem Azidus? I still haven’t solved this one. Seems like the stepper motor is underpowered (yes, I checked the voltage of the controllers, they are all at 0.92V) or maybe just jaming somehow.
i have the exact same problem^^
My Extruder clicks/can’t push the filament further.
I guess i have to check if the nozzle is clogged, but i’m not really sure how to do that…
Also it seems to be wired, that it clogs after 5 min of printing with a completely brandnew-printhead. Even settings total standart.
The troubleshooting page isn’t really a help at all, since it is just 3 sentence long explain of “remove and clean the hotend”.
It is frustrating and it seems that i’m not the only one here…
Make sure the nozzle isn’t clogged by the following steps:
Heat up
unload material
push some material by hand through the heated nozzle
if it comes out your nozzle is obviously not clogged.
(thats good! Continue:)
cut the complete 70-80 cm of filament that you had unload, so that you only insert fresh unused material
Load the fresh material
Enjoy.
I found out, that the extruder pulley accidentally ripped of some material from the filament wire, what caused the non grip on the pulley.
You can find a picture of the ripped of material from the filament wire in the linked thread.
Additionnel to Tuxx report, also have a look at the 70-80 cm you cut off. I observe some part are twisted in accordion WWWWW
It generally append when printing with many retraction. Reducing, retraction distance and speed, as stated before, could help but not sufficient for some prints which need many retraction. Another idea, will be to use ABS and not PLA for those prints.
Is it possible to get a PTFE tube with sligtly bigger diameter to prevent it geting stuck when it have been to many retraction that causes the filament to jam in the PTFE? or is this going to affect the print?
After loading fresh ABS, printer was working perfectly about 50 layers and after that it’s “skipping” some of the filament. Similar to http://3.bp.blogspot.com/-WzIozoUxThs/UWrujlwtIqI/AAAAAAAAAnA/kXg3TKepAjk/s1600/IMG_3952.JPG. It gets worse and in about 100th line barely any filament was extruded. It looks like curly hair or something, as little droppings of filament coming out of the hotend and sticking randomly at any higer point there may be. There’s nothing left of the structure it should be.
It seems that extruder motor feeds about 1cm of the filament into the tube. As it does that I can clearly see tension rising in the tube, it bends a little. Almost nothing comes out of the hotend. While the tension rises and stepper cannot push any further, tension releases by pushing the filament backwards, sliding over the stepper wheel and peeling off some of the material from the filament. It does that on regular basis. Seems like a clog.
I tried to unload the filament, but it didn’t come off. Something at the nozzle was blocking it from coming out. I preheated the hotend and pushed filament manually, little came out from the nozze but it was soft enough to allow me to pull it out. At closer looking I noticed that the tip was little bigger and with a collar-like line on it. This explained me why it didn’t came out.
After re-loading prints started off well. Perfect, I’d say.
After abou 50 layers all my problems came back. This has happened 4 times in a row now.
May the problem be in my nozzle? Maybe I’ve gave it a hit with buildtak plate little too hard.
If that may be the case - where to get spare nozzle? I’d like to test my theory.
Cut the PTFE tube with some filament in it that way you can cut cleaner.
Also I had problems with bad quality filament (grey color) the pigments that give the color were so big they got stuck in the nozzle every 5-10 minutes of printing.
Just another answer to add to the knowledgebase: check your filament thickness. I bought filament from a maker right in town (support your local economy, yada yada) and one spool varied widely in thickness. When it got a little thicker than normal, it overran the flow rate and built up backpressure until it oozed between the hotend PTFE tubing and the nozzle. When it got thicker still, it just plain got stuck in the tube leading to the printhead, stopping flow altogether. So don’t go cheap!
It seems to be a heat problem. Backpressure is not the reason, it’s the result.
Push some filament manually through preheated printhead. Remove PTFE tube from the printhead and push, you should see and feel smooth liquid flow through nozzle. Apply constant pressure, I let the weight of my hand and gravity do the job. If you cannot get constant flow or you see that filament flow is lower or it looks like a pearl neckless rather than a fishing wire, add heat 10% and retry.
If the problem disappears or seems to go better, retry until you find the temperature that opts-out the problem. If that is the case - your temp sensor may be faulty or assembled badly. Try a spare and compare temperatures with third device.
If you cannot get smooth fishing wire alike result, use a guitar string to push through printhead from top through bottom and gently pull it out. I had some plastic-alike pieces in there too. It seems that at some moment some of the filament had crystallised and formed a thin layer around PTFE tube’s inner wall, letting some of the soft filament flow through.
Low temp might be reason for the dust to accumulate and form hard pieces in nozzle that at some point clog the printhead. They wont block it (as my case), they just cause random semi-clogs randomly at any time while printing.
That’s why replacing filament works for few hours - if you pull out old wire you cut the previous end that had some of the pieces hardened at the tip.
I’ve been having the same problem. I thought it may be the PTFE tube since only the right nozzle seems to block, but I think changing the settings should help. My filament has been destroyed in the extruder due to rapid, successive retractions. I’ll post my findings.
In my opinion the main problem is that filament is getting too hot in the isolator guide(s).
Heat from nozzle and heater block(s) rises up to isolator guide and melts the filament in the PTFE tube.
2 “problems” can come together here:
Intensive retraction during a print means that you have less flow on average and less flow means more heat rising up. (the more filament is feeded during a period of time the cooler is the teflon tube because the feeded filament cools it)
If retraction distance is too high (as in the basic settings of cura) you retract melted material from nozzle to the PTFE tube.
If one of this happens and the flow increases at that time of print then you compress the melted material in the PTFE tube from 1.75mm diameter to a diameter of slightly over 2mm (inner diameter ot the tube) and then every little step (for example from PTFE tube to nozzle) will block the flow
I came to this conclusions as I sometimes had problems in unloading filament. Retraction the first few millimeters was no problem but if there was a thicker part of filament in the PTFE tube it sometimes stopped suddenly at upper end of isolatorguide (small step from PTFE to PEEK or from PEEK to under side of the coupler)
Since I increased the cooling of the isolator guides, added a “heatshield” between heater blocks and isolator guides and separated the two fans in function (different mainboard outputs for printhead cooling and print cooling) I got problems with stucking filament very rarely.
