Bambu Lab TPU 90A Filament 1.75mm 1kg

Softer than our 95A, and built for parts that flex over and over without wearing out. Bambu's target uses are shoe soles and RC tyres — anything that gets compressed thousands of times and has to keep its shape.

Two of the colours, Frozen and Blaze, are dual-tone: the colour shifts along the filament, so a print grades from one shade to the other as it builds up.

Not for the AMS, and slow going. Run it from an external spool holder — Bambu list the AMS, AMS Lite and AMS 2 Pro as all incompatible. Use a 0.4, 0.6 or 0.8mm nozzle; 0.2mm and the high-flow nozzles are not supported. This is the most demanding flexible we stock to print — see below.

At a glance

Read this before you buy it

90A is softer than 95A, and softer filament is harder to push. Bambu's own test specimens for this material were printed at 34 mm/s. The ceiling is 200 mm/s, but that is optimistic for anything with fine detail — expect long prints.

Overhang is limited to about 40°, against 55° for 95A and 70° for rigid materials. Soft extrudate sags. Design with that in mind or lean on supports, which Bambu says to turn on.

Retraction is shorter and slower than 95A — 0.4–0.8mm at 10–30 mm/s, against 0.8–1.4mm at 20–40. Pulling a soft filament back hard just compresses it in the tube. If you're adapting a profile from 95A, change this first.

If you don't specifically need the extra softness, TPU 95A HF prints far more easily and costs less.

What you get for the trouble

Young's modulus is 5.3 MPa against 95A's 9.8 — close to twice as compliant. Impact strength is 124.2 kJ/m², and it stretches past 650% before breaking.

Layer adhesion is excellent, as with all Bambu TPU: 87.3 kJ/m² across layers, about 70% of the in-plane figure. A flexing part won't peel apart at a layer line.

It also absorbs noticeably less water than the other TPUs — 0.61% against 1.08% for 95A — so it is a little more forgiving if left out.

Storage

Bambu specifies under 20% RH, sealed with desiccant, and 70°C for 8 hours to dry.