I’m looking for advice, because at this point I feel stuck and I’m not sure which direction to move next.
Background
My first printer was an A1 mini. It was an excellent machine, and TPU prints came out very clean and high quality. At that time I didn’t fully appreciate it, and I assumed the P1S would provide even better TPU results since it’s enclosed and CoreXY — but I was wrong.
On the P1S, I was never able to achieve TPU quality comparable to the A1 mini. No matter how much calibration I tried, I kept getting smearing / deformation on some corners.
Now I’ve moved to the P2S, and I managed to calibrate TPU better and get closer to the result I want.
However, I still see smearing on certain corners and edges, which is clearly visible on a 3DBenchy test print (photos below).
What I’m trying to improve
I’d like to get advice on:
How to improve TPU print quality and eliminate corner/edge smearing
Which printer type is generally better for TPU: enclosed or open-frame?
At this point I have a strong impression that open-frame printers perform better with TPU, based on my experience printing the same model on the A1 mini, P1S, and P2S — but I’m not sure if that conclusion is correct.
Material / Setup
Filament: Sunlu TPU
Filament condition: dried and cooled before printing
Storage humidity: ~10% RH (hygrometer inside the dry box)
You can easily emulate an open frame printer. Bambu used to recommend open door/top off for PLA, PETG, and TPU. Now the filament guide only shows enclosure not required. I still watch my X1C chamber temp and open door/raise top before it can exceed 30° C when using these filaments. Works great.
Just trying step by step, one by one change filament settings: temperature: -10 -5 … 0 … +5 +10 Fan speed: 30…50% 40…90% 100…100% Z hop when retract: OFF 0.2 0.4
