TPU with the XL Enclosure?
Has anyone been successful printing TPU with the XL Enclosure? Since adding the enclosure, I can't figure out a pathway to run the TPU where it doesn't bind. I was bypassing the side filament sensor and running a PTFE tube directly from my dryer to the print head before the enclosure. Since adding it, there are too many sharp turns given the openings available and the TPU keeps binding, leading to under extrusions and then clogs.
Any ideas?
RE: TPU with the XL Enclosure?
Maybe try this: https://www.printables.com/model/718498-prusa-xl-soft-tpu-cable-clip-to-extruder-prusa-xl
This reduces the frinction on the long path but still guides the filament. You can install it parallel to the existing main tube.
RE: TPU with the XL Enclosure?
Experimented some more. It looks like the under extrusion problem is more because of the filament getting jammed up in the gear than it is problems with the path. I simplified the path and made sure all retractions were turned off. Five minutes into the print I had an under extrusion, and when I checked it the filament had become wrapped in the extrusion gear.
I didn't have problems with TPU before adding the enclosure. In that process, I updated the PETG parts to CF parts. Other materials print fine after the upgrade, but I'm having a devil of a time with TPU.
I am using the hardened steel nozzle, although I think I was using that before the upgrade, too.
What further trouble-shooting recommendations do you recommend? It's frustrating that settings I used before the upgrade no longer work.
RE: TPU with the XL Enclosure?
Which hardness grade is that TPU ?. It isn’t the same a relatively hard TPU (95-98A) than a very soft one ( 70A or less ).
Anyway, I don’t own a XL, so l’m not familiar with the Nextruder, but if the gears are in direct contact with the stepper shaft, they can get quite hot after a while, more so inside an enclosure. This is a recipe for trouble with soft filaments.
Some extruders have secondary gears made from plastic ( POM usually) between the main gear of the stepper and the gears pulling the filament. This intermediate plastic part serves as an isolator, so the stepper heat isn’t transmitted to the filament. That’s very useful for soft materials like TPU, but also for PLA.
RE: TPU with the XL Enclosure?
Have you tried it again, leaving the enclosure open?
RE: TPU with the XL Enclosure?
Yes, I have not closed the enclosure during testing
Have you tried it again, leaving the enclosure open?
RE: TPU with the XL Enclosure?
Thanks for your response, but none of what you suggest applies to the Nextruder.
Which hardness grade is that TPU ?. It isn’t the same a relatively hard TPU (95-98A) than a very soft one ( 70A or less ).
Anyway, I don’t own a XL, so l’m not familiar with the Nextruder, but if the gears are in direct contact with the stepper shaft, they can get quite hot after a while, more so inside an enclosure. This is a recipe for trouble with soft filaments.
Some extruders have secondary gears made from plastic ( POM usually) between the main gear of the stepper and the gears pulling the filament. This intermediate plastic part serves as an isolator, so the stepper heat isn’t transmitted to the filament. That’s very useful for soft materials like TPU, but also for PLA.
RE: TPU with the XL Enclosure?
Where are your idler-screws are set? Standard would be that the screw tips reach the front face of the idler nut. If they are set differently, set them as they should be and try again. If they are set right, try loosening the idler-screws for about two turns and try again. If needed repeat.
You'll find out, when it absolutely lost grip because the idler flops around. 😅