I think the same… even this is a new filament, is still need to dry it first…
It depends on the climate where you live and the quality of the filament on arrival.
I have never dried a filament I just purchased and I have only ever dried two filaments after opening them.
I live in the U.K. and humidity levels are typically around 70% according to my devices.
I now own two filament dryers, the latest one, the Sunlu S4 is because I am about to experiment with carbon and glass fibre filaments.
I have never had a problem printing with any brand of TPU nor dried it at any point. I have also been using the TPU for AMS with the same experience.
so is in Indonesia, the mumidity can up to 70%…
even though I keep my filament in the air tight box, it still have the issue of birttle. if I have a filament that not use for a long time, i must dried it, if not, I can stuck in my ams or extruder. it happend many times on me…
I even ever print TPU while the filemant still dry in the sunslu s4 because the TPU keep result stringing while printing.
if that is an issue, if there is a filament hole in your drier then connect the drier directly to extruder with ptfe tube, also change the preset to whatever you are using instead of generic. hope this works
What I do is put my filament in a ziplock gallon bag (like $10 for 50) and put in the filament silica gel packet as well. I always get great results!
I have done a few kg of Sunlu 95a on Sunlu and have not had any problems.
But the last lot I used was for seals on Ikea 45L boxes – about 20 lots of seals for the filament that I store in those boxes in all. But I do dry my TPU before I use it, though, mate.