Tpu printing problem

[andrei2306 0]

i have a anycubic i3 mega s and i try to print tpu and is impossible take a look in the photo .  Is starting to print and after few second i makes like you see in the photo and also it stopes to take out fillament 

[FraggleRock 4]

I was about to post the same result with my UM3. I got my TPU from Matterhackers.

I did a dozen small test prints to dial in the settings to something semi acceptable, then went to do a larger print and I got the same result. Not sure what's going on here but something tells me that the filament gets compressed inside the bowden tube, then the tension gets released by a sudden expansion, a bit of the filament gets extruded, then it's getting compressed again and the flow stops. That's my current theory.

Edit: I see the i3 also has a bowden tube. 😕

Edited April 22, 2020 by FraggleRock