Extruder Clicking = Prints Failing
Hey all, last night, my printer just started clicking within the extruder area. I was printing all day without any issues whatsoever, I never changed the filament, and I was printing the same files that I had been printing for hours (I needed multiple copies of the same part).
So without changing anything (except cleaning finished prints off the bed), my printer started clicking and prints started failing. Unloading/Reloading filament works just fine. I factory reset the printer and went through all of the calibrations and self-test. I did the V2 calibration and it printed fine.
First layers still look great, but once the second layer starts, things go south. In fact, outlines seem to print fine and there isn't any clicking at all. The clicking only sets in when there's infill - either solid infill or interior infill (honeycomb, in this case). The only thing that looks off is my feeder tube - it actually looks a little melted up top. Could this be the issue? Check out the pics of prints. One shows how good the first layer looks and how bad (rough, missing areas) the second layer starts printing (right side). Another shows a stopped print when things were working fine, and the same exact file/print after the clicking started. Finally there's a pic of the feeder tube looking as if it's melted/damaged. If that's the case, what would cause that?
How should I approach fixing this? Thanks in advance!
Re: Extruder Clicking = Prints Failing
Clicking from the extruder means it is skipping steps. Skipping steps occurs usually if something is blocking and it can't overcome the blockage, so it skips and clicks. There's a ton of reasons why the extruder could start doing so. This kinda split looking PTFE tube might or might not be the root cause for your extrusion problems. Unfortunately, it is a royal pita to check and replace this tube.
So maybe in order to avoid having to take apart the hotend, i'd try "cold pulls" (also called Atomic Pulls or Atomic Method) first to see if we're lucky and that is not the problem and we're only looking at a partial nozzle clog. Crud accumulates in the hotend over time and can cause blockages. Cold pulls can clear those nicely.
Excessive length or amount of retractions could cause behavior like this as well. Does the problem occur with presliced files from the SD-Card that came with the printer as well?
If the first fews layers work fine and the problem gets worse the longer the print runs, you could also take a closer look at your hotend fan. If the fan isn't providing enough cooling, heat creaps up the heatbreak and filaments starts blocking.
Also, stuff like this could happen if the filament diameter on the spool changed.. Or if the filament doesn't come off the spool easily enough. (PS: if you're still using the crappy spool holder that came with the printer, this is known to cause too much friction sometimes and the results would look similar)
Re: Extruder Clicking = Prints Failing
Thanks Stephan!
With loading/unloading seeming to work without a hitch, I never knew that there could still be blockage involved. I'll try the cold pull or "atomic" method this evening. That said...
Regarding stock gcode files: I haven't done any stock gcode files but I did do another file that I've printed quite a bit - the Marvin model, with my own S3D settings, that have worked beautifully over dozens of times with just as many filaments. It successfully printed with zero clicking. However it DID have a very slightly lower quality (mostly noticeable in the loop on top) than recently printed Marvins, but it still looked good. NOTE: that model was printed at .1mm while the files that I'm now having issues with are printing at .3mm (very blocky & vertical walls). Again, I was just printing the same files that printed just fine during the day. I only started having issues at night but still printing the same files.
What's very strange is that I'm only getting clicking on infill. First layers and perimeters don't have clicking and don't look bad - just infill & infill layers. And this isn't a situation that progressively gets worse. It literally starts as soon as the second layer starts and any time there's any form of infill.
But you made me think about my hotend fan. I recently did the Noctua 40mm fan mod with this shroud: https://www.thingiverse.com/thing:2076234
It's SO QUIET that it's barely audible at all which made me worry about its cooling effectiveness but I've only ever heard praise for this mod which is why I did it. And until last night, it's been great. No problems whatsoever and MUCH quieter. Seems like a win-win unless I missed a big negative to it. The only hiccup I've had with it is that even though the fan spins up, I'll get a "wiring error" during a self test. Yet, if I run the self test again, it passes just fine without changing anything. Thought that was worth mentioning.
Also worth mentioning: About a week ago, I upgraded to the latest firmware on the website (3.0.1.1) and I've noticed a few things. There's a new down-up movement when unloading filament and now my filament comes out REALLY stringy. Like, I have to pull and pull and pull before the wispy stringy filament stops coming out. It didn't do that before the firmware upgrade. I wonder if this has led to my current issues.
I am using the stock arms for the spool holder, yes, but I printed out a cylinder to hold the spool better: https://www.thingiverse.com/thing:1666699 I also gave the hotend plenty of slack so it didn't have to pull it directly off the spool and it didn't help. I also tried tightening the two spring screws on the hot end and that didn't help. Someone else mentioned that I should loosen the screws to the lowest effective tension as too much tension can be just as bad as not enough. So I'll try that along with the cold-pull method tonight.
Finally, I noticed that the little hex screw holding my extruder gear on (seen in the extruder pic) is stripped. I can't unscrew it. What's the best way to get that thing out and replaced? Drill? I wonder if my gear could be off juuuuuust enough to cause problems?
Thanks!
Re: Extruder Clicking = Prints Failing
Okay, so, between Stephen's advice and other threads' suggestions, I went ahead and did the cold-pull technique four times, twice with two filaments and I loosened the extruder screws to the loosest effective tension. Guess what? IT WORKED! See attached pic of the four pulls and the results on two different prints that were failing only 24 hours earlier.
BTW, if anyone sees anything alarming with the four pulls (like, why are they so different between the two filaments or if they have any extra ridges, indents, etc) PLEASE let me know! If there are any red flags, I'd like to take care of them sooner or later so they don't cause any larger problems down the road.
And, BTW, THIS [help] is why I bought this printer and joined this helpful, dedicated community. THANKS EVERYONE!
AND THANKS JOSEPH!