mega clog on hotend

[carlos]

So this giant clog occurred on a print that I left running when I went away for a couple of hours. I haven't gotten the chance to do anything about it as of yet since I had some other things to attend to. But doing a search on here, most of the information has covered clogged hot ends or extruders. Any recommendations to taking this apart?

And I'm pretty psyched my first clog was a big one! Kinda wished I had a nice time-lapse of this.

Cheers!

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[cacb]

Wow... that's a bad case of over-extrusion!! I have not seen anything like that before....

Maybe you can first try to unscrew the 4 screws holding the fan and fan shroud. Then perhaps heat the hotend to ~170C for example, so that the hotend can come loose. Also remove the filament, you don't want more plastic in there. Maybe drag the whole thing off by holding onto the fan shroud when the hotend is hot? It does look like you may have to print that fan shroud again afterwards.

Hope it is possible to remove without any damage!

[PxT]

Been there, done that. Several times.

Your hotend is actually not clogged per se. Because of the big mess underneath you know that filament must still have been flowing freely, so the good news is once you remove that blob you're probably good to go.

As said above, get everything up to temp and carefully pull off your new artwork / blob without burning yourself. Print a new fan shroud and you're back in business. And look into your bed adhesion - this happens when the print comes loose from the bed.

[frankv]

Beware that your wires to your thermistor and nozzle heater are in that mess. It would be very easy to break these as you try to clear it up.

I found that tin snips are actually pretty good at cutting up PLA. I'd try and clear the bulk of the plastic that way.

[carlos]

Thanks for the tips and it was quite helpful. Glad to report that the fan shroud was unharmed.

Thankfully the fillament just squeezed it's way up and out, but I think it was due to the heat shroud protecting and keeping things in place
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The heat shround is now completely solid, not sure if I can save and reuse it.
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I heated the hotend to about 120 and that helped melt some of the filament. Slowing clipping away with wirecutters making sure to be super careful around the wires.
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I removed a pretty good amount and was able to wipe most of it off using a flat edge to get inbetwwen the grooves.
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The culprit of this ill-fated clog i'm thinking is due to the base layers corners lifting off the bed. The hot end caught a raised corner and probably dislodged the print off the bed.
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You can see some warping on the bottom, I guess I might have to do a little more calibration.
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Is there a recommendation for the heat shroud, not so sure it's worth paying $10 just to replace it.

Also I wasn't sure if that was white teflon tape. I'd like to replace it, but wanted to make sure if anyone can confirm exactly what is used.

Thanks you all again for the tips, so far so good.

Cheers!

[plexus]

This is definitely a "First Blob" post! well done!

[teicher]

Correct, the tape is just white teflon tape, the same stuff you use for plumbing repair. It's also used on the threads when you attach the tip to the hot end. If I were you, and I just recovered a printer with nearly the same failure you experienced, I wouldn't bother replacing the teflon tape. You can wipe it down pretty well if you heat up the hot end to 180+ and use a clean shop rag. That's what I did and it's been fine ever since.

The insulation sock is just automotive fire sleeve hose, you can find it in short lengths (12") on ebay for about $5. You might also try an auto parts store. No way would I pay $10+ shipping to get it from the printrbot store.

[PxT]

If you don't want to hunt around for a replacement you can probably salvage the sleeve with a small propane torch or a heat gun. Melt all the plastic out of there and the sock should be pretty much no worse for wear. Some residual plastic will probably be meshed into the fibers and hard to get out, but you'll be able to slip it on to the hot hotend.

eBay is a good choice too, but when I bought mine I couldn't find the same tight weave that PB uses, the length I bought has a much looser weave to the fibers on the inside. Still functions the same though.

[carlos]

@plexus Ha, I never thought of it as a blob, but it sure is.

@teicher thanks for letting me know about the teflon tape. As for the fire sleeve hose is it an 1" diameter or less?

@PxT I was wondering about that. I'll try to see what I can salvage otherwise it's ebay.

[teicher]

It's 1/2" 12mm I believe.

[carlos]

Thanks, @teicher. Looks like I'll have to go and buy a replacement. There's no saving the old sleeve.

Appreciate all the help.