Blissful, Wonderful.... >>> UGH, Messy

[cratica]

I have a Rostock Max v2, all stock, running base settings from website (speed, temps, etc... all stock)

I've been successful in printing a number of large prints for clients (sure have had some issues with warping and whatnot) but the hotend always was consistent, smooth, etc...

Until yesterday. About 8 hours into a 9 hour PLA print I heard a loud popping noise. It was the feeder and it seemed like the filament was having a hard time getting fed through the hot end. The last few lines of print was messy, bumpy, stringy and inconsistent. Not sure what to do, I slowed the speed down manually to the min speed which helped a bit and I was able to salvage the print (but you can clearly tell the quality went south at the end).

Following tech supports advice, I removed the top portion of the hot end and tried to force feed a piece of filament through at a lower temp (180/185). It worked with a bit of effort but still the output was much finer than what I expected. I put it back together and still had problems with the print. Basically it just seems that it can't get filament through the hotend consistently as at times it leaves drops or a very thin string rather that a nice smooth line as it had been since I built it.

So I set about today, recalibrating everything including the autotune for the heat and the bed. Then tried it again, same issues persist.

So I removed that roll of filament and tried a new roll of ABS. Still same problems. Very poor, stringy, clumpy output.

Please remember that everything has been working fine for the past 2 months with numerous prints until 8 hours into a 9 hour print yesterday. It happened suddenly and since then it's been consistently crappy output. For me, an 8/9 hour print is a quick print. Most of my other work has been in the range of 40-60 hour prints, all without these issues.

Was very happy with this printer until yesterday. Any help would be appreciated as my client is eager to get his prints asap.

Thank you,

Curtis

[Earthbound]

I would guess there was debris in the filament. Something that is too large to pass through the nozzle tip. There must be a way to remove it, but I don't know the process. Easy solution is a new nozzle.

[geneb]

Check this out: https://www.youtube.com/watch?v=JX65_rpc4m8

The guy deserves a nut kick for the portrait video though.

g.

[lightninjay]

Yeah, I had a similar issue that I think I figured out the culprit.

The PTFE liner inside my SeeMe hotend seemed to have gotten too hot and deformed slightly during a long print, and caused the liner to deform enough that it was generating back-pressure.

Once I disassembled the hotend, unjammed all the PLA and gunk that had accumulated, I pulled out the PTFE liner and reshaped it to easily feed 1.75mm filament through once again.

Since then, W.I.S.P.E.R. seems to be printing fine. I'm currently in the middle of an electric cello build for my thesis project, more details to come in a dedicated thread once I have more to show off.

I think the real issue is leaving the hotend at full temperature for extended periods of time without extruding any plastic, so the plastic gets hot enough and expands, deforming the PTFE.

[cratica]

Thank you. It seems to be the nozzle tip, perhaps gummed up with contaminents in the filament? That and the feeder seems to have lost its grip. Don't understand why it happened suddenly with no warning. Ordered 2 more nozzles so hopefully that will get me going again.

[cratica]

Thanks for the video link. I'll see if I can' pick up a tiny drill bit like that to clear what I have.

[626Pilot]

When some piece of grit gets lodged in my hot end, I usually remove it and blowtorch it for a minute or two. Any plastic inside is vaporized. If there is still blockage, I take a piece of stranded wire, remove one of the strands, and use that to poke out whatever's in the way. I think a PCB drill might also work. Whatever you have around that's narrow enough to get in there should do the trick.