TPU-90A Foam Filament – Cushioned Foam Texture, 1.75mm, 1kg

Shore A measures resistance to indentation — the lower the number, the softer the material. At 90A you get soft flex with noticeably more structure than the 70A–85A grades: it bends and rebounds well but holds its form, which suits phone cases, bumpers, and hinges. It also feeds more reliably than the softer grades. TPU Shore hardness explained covers where each grade earns its place.

Yes — TPU is hygroscopic and picks up moisture faster than most filaments. Dry it as soon as you hear popping or see bubbles, heavy stringing, weak layers, or a rough surface, and print from dry storage whenever you can. How to dry filament at home compares ovens, dry boxes, and dedicated dryers; how to store filament properly covers keeping it dry between prints.

Direct drive is strongly recommended. At this softness the filament buckles easily in a long Bowden path, so you want a short, constrained route and very low spool resistance. See TPU Shore hardness explained for how feeding difficulty tracks with grade, and our AMS and multi-material setup guide for feed-path considerations.

Moisture is the usual culprit. Dry the filament first — how to dry filament at home covers the options — then lower the nozzle temperature or adjust retraction carefully and keep travel moves efficient. TPU needs a different retraction approach from rigid filaments, which our step-by-step retraction tuning guide covers material by material.

It depends on your printer and feeder. Flexible TPU can buckle or jam in the long feed paths these systems use, so run it from an external spool with a direct feed unless your equipment manufacturer explicitly supports this hardness. Our AMS and multi-material setup walkthrough covers what to check before loading a flexible spool.

Print slowly, calibrate flow, limit acceleration, keep the filament dry, and avoid building excessive pressure at the nozzle. Always test a small calibration part before committing to a production run — what a calibration print tells you explains how to read the result rather than just eyeballing it.

Raise the nozzle temperature gradually and reduce flow to compensate for the foaming expansion. Calibrate with small test samples, because how much it expands changes with temperature, speed, layer height, and hot-end design. TPU Shore hardness explained covers how the Foam finish behaves differently from Glossy and Matte.

Work at the lower end of the nozzle-temperature range and move the flow ratio back toward 100%. Less foaming expansion means a denser, firmer, more dimensionally predictable part. Test on a small sample first — a calibration print will show you the trade-off clearly.