Printer jams when enclosed
It sounds obvious now, but diagnosing it took forever. I used cardboard boxes to build an enclosure, and the heat inside seems to soften the filament to the point that the extruder gear digs into it, causing a failed print. It acts jammed, so that's how I tried to fix it, but no amount of tweaking worked. The prints would always fail about an hour in, which was my main clue.
Anyway, can anyone think of a way to prevent this? I'd like the least amount of warping possible, and the enclosure also serves as a fume hood with a duct running outside. The whole fume thing is moot with the door open, but I have to sleep next to it while it's printing. I'll try turning the fume fan up all the way in the mean time. Thanks in advanced.
RE: Printer jams when enclosed
I'd try to measure the temperature inside. My temp is always below 40C (carpet enclosure). You can also lower the nozzle and bed temperatures, I am usually lowering 5C nozzle and 3C bed for pla - the difference however always depends on outer conditions and used profile.
RE: Printer jams when enclosed
I'm printing with PC. So the bed temp wants to be 105C, with the nozzle 290C. Is it possible to record the heat break temp? The extruder assembly might be getting hotter than the air because of it's proximity to the bed and nozzle. Maybe I just need an additional exhaust fan. Like you said, I should record the air temp right when it stops, so I can share the PSA "printer jams at X enclosure temp"
RE: Printer jams when enclosed
I don't know if the Nextruder is more prone to heat creap but I have printed quite a bit of Prusament PC-Blend with my Mk3s in an enclosure and got up to 45°C in the enclosure. Never had any clogging issues. My hotend temp was 285°C but the bed was even 110°C or so.
I take it you are not printing pure PC but some kind of modified PC or PCCF, right? Most "PC"s for the hobbyist sector are modified. If you were to really print pure PC, I'd be not suprised about you experiencing all kinds of troubles. Neither XL or Mk3/4 are made for that.
What filament brand/type are you using exactly? Like I said, I have had good experiences with Prusament PC-Blend which also does not seem prone to cracking like some other modified PCs out there.
Mk3s MMU2s, Voron 0.1, Voron 2.4
RE: Printer jams when enclosed
Prusa's Carbon fiber blend polycarbonate. My mk3.9 didn't have any issues either. I wonder if it's because the whole bed was heated to the max? It radiates an incredible amount of heat. Even the tool carriage was hot to the touch, and that doesn't produce any heat itself.
RE: Printer jams when enclosed
I don't have any printer with a nextruder but from what I have read, there are mods out there to guide air to the heatbreak fan from further upwards and not directly from the bed. I don't know if that is feasible for the XL, ie if that mod clashes with anything.
Something like this: https://www.printables.com/model/602883-prusa-mk4-hotend-fan-shroud
Mk3s MMU2s, Voron 0.1, Voron 2.4
RE: Printer jams when enclosed
Honestly for long prints of PC, I would use external air for hotend or liquid.
I found this one https://www.printables.com/de/model/794809-prusa-xl-nextruder-cooling-airbox, maybe something which would work.
In my case PC is no Problem the XL enclosure gets to 42°C and no problems.
But it seems there is problem sometimes with ASA (read somewhere in this post from MME: https://forum.prusa3d.com/forum/original-prusa-xl-tool-changer-user-mods-octoprint-enclosures-nozzles/ideas-to-make-enclosure-for-xl-multi-tool/ ) he tried to use other tubes with greater inner diameter
RE: Printer jams when enclosed
I had a similar issue with mine printing ABS in the Sumo Enclosure. I ended up needing to replace the tensioner parts with ABS due to the original PETG parts warping. Since switching to ABS I don't have jamming problems.
RE: Printer jams when enclosed
I had same problem. Reprinting below parts with ABS - resolved an issue.
idler-lever-b.stl
idler-lever-a.stl
idler-swivel.stl
idler-nut.stl