Hi all. This is an update to this post. I don't know what else the community can do to help, but I figured I'd throw some more content up there and give something bored people to look at.
Since the last update on that post, I tried working on the printer in freezing temperatures (not really but it's cold in this house) with extremely precise practices on assembling the hot end (the same hot end I had haphazardly assembled dozens of times and printed with zero issues) and yielded zero progress. Today, I tried a brand new PTFE lined heat break, along with a brand new Capricorn Bowden tube (I already had one but I needed more tubing for the heat break). Clogging in the same exact way in roughly the same amount of time as every other attempt. It's as if I've not tried anything, literally nothing is effecting the results.
I considered ordering a fancy micro-swiss or ed3 hot end, but at this point, including the stock hardware, I've gone through 6 heat breaks, 3 heat blocks, a half dozen nozzles and a foot of Bowden tubing, none of which did anything to fix my problem (or even make it worse). I would look to the extruder, but I outlined in the previous post the testing I did to rule that out (able to run >1m of filament at high and low speeds through the Bowden tube).
I'm at the end of my wits. Perfectly good printer cranking out multiple high detail prints a day, now completely useless over something so stupid as clogging. Where the hell else can I look? Could it possibly be some sort of software/firmware issue, where Klipper isn't sending or receiving the right commands or something? I know my slicer settings are at least good enough because I've tried both prints that have completed dozens of times as well as new prints with drastically reduced retraction. Do steppers need to be tuned over time? I don't think it makes sense that after a year it'd suddenly become so uncalibrated it's unusable, and when I tried calibrating it before I was just unknowingly calibrating against mild clogs, but I don't know where else to look.
I can't recall of you said it clogged while just feeding through the hotend without printing, totally possible you could have an intermittent break in a wire going to the hotend, TC would be obvious but others less so.
Did anything change to your setup before it started? Are you using a new version of a slicer? Did you update klipper? Is your extruder stepper getting warmer than usual while printing?
No clogging while feeding without printing. If there was a wire break in the thermistor, Klipper would shut off, and if the hotend was cutting off I should see fluctuations in the temp chart.
Everything except the nozzle was exactly the same between the last print the finished perfectly and the first print that started clogging. I've since rebuilt almost the entire hotend multiple times, including a few different nozzles. Klipper and all the plugins are the same versions, and I felt the extruder motor last night during the last clog and it was still room temp.
TC break could shutdown, but depends, I had a break on my prusa that would cause the readings to jump around as it wasn't quite long enough to fall totally off, caused the firmware to hunt and ran into thermal runaway. Wondering if a fault in a heater wire could cause less obvious issues as thermistors aren't super quick to respond as far as I recall, combine that with thermal mass of your block (copper blocks have a sizeable thermal mass) and you could essentially mask the issue. Not saying it's a break just something to think about checking as they often can be some of the most annoying and hard to pinpoint failure modes.
Have you done an extrusion calibration? If you call for 100mm of filament is it feeding 100mm? Same filament? Is it possible it's wet? I've had clogging issues with filament not being dry before. Can you get a successful print if you slow things down or increase temperatures? Possibly even trying less part cooling? Lastly, do you have a sock on your hotend?
Calling for 100mm gets me 100mm if I'm just extruding through the Bowden tube, but once I run it through the nozzle it starts clogging and can't extrude the full 100mm. I've tried multiple filaments, all are properly stored and 2 of the rolls I've used have completed prints within hours of the beginning of the issue.
I'm not even attempting prints anymore. I'm literally just extruding filament through the heated nozzle and it's causing clogs. I've tried extruding at both high and low speeds, it doesn't seem to make much of a difference.
No, but I haven't had one since it got ripped apart shortly after getting the printer. If a lack of a sock was going to cause issues this bad it would've happened long ago.
That's super frustrating, sorry you're experiencing it. Sock won't stop clogging but is great for stopping buildup, I've scrapped a block or 2 because petg filled in the setscrews and degraded and can help with nozzle buildup.
Do you have cleaning filament? It might be worth passing some through as a hail mary, I've unclogged nozzles before that way. Do you still have the last good config you could try? Do you have different filament as well? I had something like this happen with some petg, would clog constantly for no apparent reason, swapped brands and hasn't come back.
It's a standard e3d v6 style hotend yeah? I'm clumsy and tend to not be the most delicate, I had issues with them because I'd slightly move the block while tightening the nozzle or accidentally mess up wires because of where I had the wrench to hold the block still. Not helping you now but I swapped to dragon hotends which are more or less a drop in replacement, been a lot easier to maintain and I definitely look to get better results.
I don't, but I've used numerous cleaning methods and am 99.9% sure that debris isn't causing the issue. (It still is happening with brand new hot end components right out of the packaging.)
Unfortunately this is the last good config. The printer had literally just finished a print and all I did was change the nozzle (done hundreds of times over the last year of printing) and since then it's never completed a print. I've also tried I think 3 or 4 different rolls of filament, one of them was the filament in the printer when it finished it's last print, so it was known-good literally minutes before disaster.
Also yes, standard v6 style hotend. I have a couple tests I'd like to run today to try to further diagnose my issue, if the issue somehow points towards the hotend I think I'm going to go for a micro swiss [or look into the hotend you mentioned if it's a drop in replacement (since I can't print any new mounting brackets...)]. I really don't want to get a fancy hotend since this printer is now available from the manufacturer for ~$30 more than the micro swiss. So I'm hoping it's something else.