SUNLU offers high-quality TPU (Thermoplastic Polyurethane) filaments in 90A and 95A Shore hardness variants, tailored to different requirements in flexible 3D printing. The main difference lies in the Shore A hardness scale, where higher values indicate a firmer material. 90A is softer and more elastic, while 95A is stiffer and more rigid – however, both remain highly flexible compared to rigid filaments like PLA.
Understanding Shore Hardness
The Shore A scale measures resistance to indentation in flexible materials:
- Lower values (e.g., 90A) → softer, stretchier.
- Higher values (e.g., 95A) → firmer, better shape retention.
For context: 95A feels like hard rubber (e.g., a shopping cart wheel), while 90A is slightly softer and more compressible.
Key Differences: 90A vs. 95A
| Aspect | TPU 90A | TPU 95A |
|---|---|---|
| Hardness | Shore 90A (softer) | Shore 95A (firmer) |
| Flexibility/Elasticity | Higher elasticity, stretchier and more compressible. Ideal for repeated bending. | Good flexibility, but less stretch; better shape retention under load. |
| Durability/Wear Resistance | Excellent abrasion and impact resistance; superior aging resistance. | Excellent, with slightly higher surface hardness for high-friction applications. |
| Printability | More demanding: requires slower speeds to avoid buckling/stringing. | Easier, especially with Bowden printers; supports higher speeds and better dimensional stability. |
| Print Settings (SUNLU Recommendations) | Nozzle: 220-240°C Speed: ≤40mm/s Bed: 50-60°C | Nozzle: 190-230°C (lower range allows 50-120mm/s) Bed: 50-60°C |
| Shared Features | Both: 1.75 mm diameter (±0.03 mm tolerance), bubble-free, vacuum-sealed, antibacterial/mold-resistant (specifically highlighted for 90A), oil-resistant. | Same as 90A. |
These images show bending tests and comparisons – note how softer TPUs (like 90A equivalents) deform more easily.
Best Applications
-
Choose 90A for maximum flexibility:
- Phone cases, watch straps, shoe insoles/soles.
- Seals, gaskets, plugs that require high compression.
- Wearables or parts with extreme bending/shock absorption.
-
Choose 95A for balanced flexibility with structure:
- Tool handles, protective covers, drone parts.
- Tires, rollers, or items subjected to friction.
- Sports equipment or everyday items that require impact resistance without excessive softness.
Both are excellent for everyday scenarios such as custom protective gear or functional prototypes.
SUNLU Spools
SUNLU TPU spools look similar across variants, with clear labeling of the hardness.
Final Thoughts
If you prioritize ultra-soft, highly elastic prints and don't mind slower printing, choose SUNLU TPU 90A. For easier printing, better precision, and parts that hold their shape, 95A is the versatile choice – it is the most common TPU hardness for a reason. Both offer typical SUNLU quality: excellent layer adhesion, no bubbles, and long-lasting performance.
Test a small print to feel the difference – the 5-point hardness difference makes a noticeable impact!
