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Nextruder stops Nextruding mid print - AHHHH
 
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Nextruder stops Nextruding mid print - AHHHH  

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Nuancer
 Nuancer
(@nuancer)
Member
Nextruder stops Nextruding mid print - AHHHH

Hey there, I've attempted to solve this with support for MULTIPLE MONTHS and I'm getting nowhere, so I turn to ya'll <3

 
I built the printer and have had incredible success for about a year of nonstop printing. The printer has reached 90+ days of print time already. It has been in a Prusa enclosure for the last 4 months.
 
I've had a problem where my prints are perfect, and then after some time, the print stops extruding, but the printer keeps printing as if it is. I come back to a "complete print" only to find it has printed only 2-20 layers before stopping. When this happens, I can attempt to unload the filament. It does not unload completely, and I need to open the Idler lever and pull on the filament with some force to free it. The filament does not appear to have a buildup/clog at all. Reloading it works fine and it purges without issue.
 
This has happened on dozens of different .bgcode files. I print in only PETG and PLA. Same issue occurs with either filament.
 
I am attempting to use this in a professional video production setting and it is making me look like a fool. I am begging for your help, please.
 
Here's what I've tried:
Update firmware to most recent
Update slicer (prusaslicer)
Replaced parts:
Idler Lever
Nextruder cover
Nextruder Main plate
Cold pulls
Recalibrate
Swap to new hotend assembly completely
Tried different nozzles (.25, .4, .6)
Adjusted idler tension
Disabling filament sensor
 
 
Attached is the following:
-Photos of the Nextruder assembly with AND without filament loaded (filament is Prusament PLA galaxy black)
-Video of the problem occuring
 
 
[UPON REQUEST] I can provide a 3mf file of one of the prints that failed (it's happening across many different bgcode/3mf files) 
 
 
 

PHOTOS

 
 
VIDEO OF PROBLEM
 
 
 

 

This topic was modified 2 months ago 2 times by Nuancer
Posted : 06/08/2025 10:25 pm
Artur5
 Artur5
(@artur5)
Honorable Member
RE: Nextruder stops Nextruding mid print - AHHHH

Different nozzles won’t fix the problem and a new hotend neither. It happens not only with PLA, but with PETG as well. These symptoms are typical of heat creep, You say that the printer has been in a Prusa enclosure 4 months, so last summer it wasn’t there and you had no problems. I bet this is it, keeping the machine enclosed during summertime is a nice recipe for heat creep, specially if you keep closed the doors of the enclosure when printing PLA. With PETG heat creep isn’t very usual, but it could happen as well, although it takes more printing time.

No real definitive solution with a low efficiency heatbreak like the Nextruder, but it will help a lot if you open the doors of the enclosure and, in summer, try to use the machine when the room temperature is lower, If you already keep the doors open, and the problem still happens, there’s not much else you can do except relocating the printer to an air conditioned room, but that’s not always possible or convenient.

What surprises me is that you’ve been in contact with Prusa support for months and they haven’t been able to locate the issue. I expect you told them that you’ve been using an enclosure the last months ?.

Posted : 07/08/2025 5:38 pm
Nuancer
 Nuancer
(@nuancer)
Member
Topic starter answered:
RE: Nextruder stops Nextruding mid print - AHHHH

Thanks for the thoughtful response. 

Heat creep sounds plausible for sure. I've tried printing with the doors open to no avail. I've experienced the issue with PETG for sure as well but I'll do more testing.

And yeah, I've been pretty disappointed by the support response. I've told them everything here and more.
I only get a response once every several days, and they fully ignored me when I suggested it might be heat creep....

 

Posted : 07/08/2025 6:27 pm
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