P1S stops pulling TPU

Bambu Lab P1 Series Troubleshooting
1
  • Detailed description of the problem: After a short while, say 30-40 minutes, the filament is no longer pulled into the printhead
  • Printer model used: P1S
  • Slicer settings used: Default
  • Type of filament used TPU Creality Type CR

I have no previous experience with TPU, nor with the use of the external spool, as I always have used the AMS, which of course is not possible with TPU.
The wire has been dried 2 x 5 hours, and came from a sealed package.
It sets of with no problems, but after some time it stops printing, but continues making all the needed movements with the printhead, no error codes, it just continues to run, but does not extrude. After the first issue I thought that the nozzle was blocked, and hence the next run was done with a higher nozzle temp. (240°>250°C). then it stopped even quicker. I manually pushed the filament ito the tube, and it started to extrude again, so my conclusion was that the gears are slipping or something on the soft filament.
Fans, are ON. door open.
I printed this with de default settings for TPU, and I know a member which has the same machine and has good results with the Generic settings.
Is there a possibility to increase the pulling power of the printhead?
I feed this from the dryer right next to the printer, and use a short guiding tube. The filament is pulled from the dryer with no resistance, as it has roller bearings in the bottom, so it is extremely easy to pull it from the box.
Or should I just LOWER the nozzle temp?
Any suggestions are welcome.

2

Check the spool to be sure the end of the filament did not slip under an adjoining wrap, creating a knot around the spool. This sort of tangle might let the filament come off the spool easily at first, but gradually tighten as the print continues.

3

Thanks for your interest, and I do know this type of problem, but this is NOT the case now, therefor I stressed above, that it is extremely easy to pull the wire from the roll, even after it had stopt extruding. This make filament is very nicely spooled up, though it is also the first time I bought this make.