Guide
TPU for beginners: flexible filament without the frustration
The first time you bend a print and it bounces back, 3D printing feels like magic again. TPU makes phone cases, gaskets, bumpers, tool grips, wheels, and camera mounts that survive drops PLA wouldn't. It has a reputation for being difficult — mostly earned on decade-old printers. On a modern direct-drive machine, TPU is just slow, not hard.
The three rules of TPU
1. Dry it first. TPU drinks moisture from the air faster than any common filament, and wet TPU prints bubbly, rough, and weak. 55 °C for six hours before printing — see thedrying guide.
2. Print it slow. 20–30 mm/s to start. Flexible filament pushed too fast buckles inside the extruder like wet spaghetti. Direct-drive printers can go faster once dialed in; bowden setups should stay slow and patient.
3. Calm the retraction. Retraction yanks filament backwards — rubbery filament hates that. Reduce retraction distance to a minimum or disable it, accept a few strings, and trim them after. Strings on TPU trim cleanly with a flush cutter.
Starting settings
| Nozzle | 220–240 °C |
| Bed | 40–60 °C — TPU grips the bed easily |
| Speed | 20–30 mm/s to start |
| Retraction | Minimal or off |
| Cooling fan | 50–100% |
| Infill | 10–20% for squishy, 40%+ for firm |
A trick nobody mentions: infill percentage is your squishiness dial. The same model at 10% infill is a stress ball; at 50% it's a shoe sole. You control the feel of the part in the slicer, not in the filament aisle.
What to print first
Start with something small, flat, and support-free: a cable tie, a drawer bumper, a simple phone stand foot. You'll learn how TPU flows on your machine in a 30-minute print instead of ruining a six-hour case. Then move up to the classics: device cases, controller grips, GoPro mounts, furniture feet, and gaskets for anything that rattles.
Wondering whether your project should be TPU at all? TheFilament Pickersorts that out in five questions — and thecost calculatorknows TPU spools run pricier than PLA.
Common questions
Can my printer print TPU?
Almost certainly yes — the question is how fast. Direct-drive printers (Bambu A1/P1/X1, Prusa MK4, most modern machines) handle TPU well at moderate speeds. Bowden printers (older Enders and similar, where the motor sits away from the print head) can too, but only slowly — the long tube gives the floppy filament room to buckle.
What does the Shore hardness number (95A, 85A) mean?
It's how squishy the filament is — lower numbers are softer. 95A is the beginner sweet spot: clearly rubbery, but stiff enough to feed reliably through the extruder. 85A and softer print beautifully soft parts but are genuinely difficult to feed. Start at 95A.
Why does my TPU print look bubbly and rough?
Moisture. TPU absorbs water from the air faster than almost any filament, and wet TPU steams in the nozzle, leaving bubbles, rough surfaces, and weak parts. Dry it at ~55 °C for at least 6 hours before printing — for TPU this isn't optional maintenance, it's step one.
Do TPU prints need supports?
Avoid them if at all possible. TPU supports weld themselves to the print and, being rubbery, can't be snapped off cleanly. Choose or orient models so they print support-free — most TPU-appropriate models (cases, gaskets, feet, grips) are designed that way already.