Which TPU hardness (85A/90A/95A/64D) should I choose?

Hardness is the grade on the spool, when a sheet or this catalog actually stores it. Flexible parts and TPU printing are the print-settings pages. TPU on a Bambu or a Bowden path is the feeder question. Drying is where the comments actually land. Siraya's biocompatibility line is quoted on medical and skin contact. It is not a reason to pick 64D.

Four grades, four different kinds of evidence

Bambu TPU 85A lists 200–250 °C (392–482 °F), a bed of 30–35 °C (86–95 °F), and drying at 70 °C (158 °F) for 8 h. This catalog stores shore 85. Bambu TPU 90A lists the same nozzle, bed, and drying cycle, and stores shore 90. Both drying lines were checked 18 October 2026. Prusament TPU 95A lists 220–240 °C (428–464 °F) and a bed of 55–75 °C (131–167 °F) from the Open Filament Database, dataset imported 13 October 2026. The product page was checked 20 October 2026. Shore is not a separate field. Drying at 60 °C (140 °F) for 6 h on that row comes from Prusa's drying article as a material default, not from a TPU 95A datasheet.

Siraya Flex TPU 64D, page read 23 October 2026, lists Shore 64D by ISO 7619, a nozzle of 240–270 °C (464–518 °F), a bed of 45 °C (113 °F), drying at 50–60 °C (122–140 °F) for at least 4–6 h, and a print speed of 30–80 mm/s. The key features call that hardness semi-rigid. The catalog shore cell is empty. Kexcelled K8 TPU 64D lists 215–235 °C (419–455 °F) on the page checked 21 October 2026 and does not list a bed or a shore value here.

What the community says

a Reddit thread in r/FixMyPrint says the surface looks like felt.

a Reddit thread in r/FixMyPrint: blames moisture and prefers a food dehydrator to an oven.

a Reddit thread in r/FixMyPrint says 4 hours is short and that people state 10 h.

Questions