Bottom line: flexible footwear parts in TPU need the right hardness, wall thickness and geometry to balance comfort, rebound and durability. Softer grades feel more compliant but wear faster; harder grades last longer but feel stiffer. Test the assembly under repeated loading before committing to a design.
Design factors
| Factor | Effect |
|---|---|
| Hardness | Comfort and rebound |
| Wall thickness | Support and durability |
| Geometry | Load distribution |
| Infill | Damping and support |
| Surface texture | Grip and appearance |
Printing notes
- Use direct drive or a short feed path.
- Keep retraction short.
- Use moderate speed.
- Dry the filament.
- Validate with cyclic loading.
Costly mistakes
- Choosing only by hardness.
- Too-thin walls.
- Excessive retraction.
- Wet filament.
- No wear or fatigue test.
Buyer / engineer checklist
- What comfort level is required?
- What load and cycles apply?
- Are walls and infill dimensioned?
- Is the feed path suitable?
- Has the part been tested?
Describe the footwear part and use and we can recommend hardness and structure.TPU advice