TPU curls up in extruder
I'm trying to print TPU 95A with the Core One L. I was able to get exactly one print out working and now everytime I print TPU after some while I get loud clicking noises from the extruder and when I stop the print and open up the extruder side I am greeted with some variant of this:
The filament curls up and then gets into the gear and nothing comes out of the nozzle anymore. The filament is dry, I already tried losening the idler and I'm using a modified Generic Flex profile with disabled retraction. I'm not sure why that one print worked but right now everything TPU is just ending up with curled filament. What am I doing wrong here?
RE: TPU curls up in extruder
Cant help sadly, but I experienced the exact same thing today (without disabled retraction however, I used the manufacturer recommendation of 2mm). Restarted the print same issue just at a different point but still on the first layer Using a 94A TPU filament
RE: TPU curls up in extruder
Are you using the high flow nozzle? Is it possible that it's partially clogged and can't support the flow rate?
RE: TPU curls up in extruder
So I was finally able to make it work reliably by using a 0.6 mm standard nozzle and a modified version of the Generic FLEX profile that comes with Prusa slicer. I did a lot of trial and error to really get it down to minimal modifications and in the end the only change I needed to make to the profile was to reduce max volumetric speed down from 3.5 cubic millimeters per second to 1.8 cubic millimeters per second. I first tried modifying the Prusament TPU profile but that didn't work at all. I think using the generic flex profile with just this one modification is the easiest way to at least get something working. It will not be super fast but I prefer reliable over fast and I usually only print small TPU parts so I can live with them taking half an hour or an hour instead of 15 to 20 minutes.