TPU Flexible Printing Guide: Shore Hardness and Which Parts It’s Ideal For

When it comes to flexible printing, the first material that comes to mind is undoubtedly TPU (Thermoplastic Polyurethane). It is one of the rare materials in the 3D printing world that offers both flexibility and durability. Thanks to its rubber-like structure, it is ideal for producing parts that absorb impact, bend, and resist compression. But is all TPU the same, and which applications is it the right choice for?

What Is Shore Hardness and Why Is It Important?

The most critical characteristic of TPU filaments is the Shore hardness value. This value indicates how soft or hard the material is. The most common TPU hardnesses in 3D printing are:

• Shore 95A: Hard TPU — Close to rubber but quite durable. Suitable for drone landing gear, in-car accessories, and industrial gaskets.
• Shore 85A: Medium hardness — Offers an ideal balance for phone cases, protective covers, and vibration dampeners.
• Shore 75A and below: Soft TPU — Feels like real rubber. Preferred for baby products, wearable accessories, and sealing elements.

As the Shore value decreases, filament extrusion becomes more difficult. While TPU below 85A can cause feeding issues on Bowden-style printers, direct drive printers can easily print even the softest TPUs. Therefore, if you are considering producing flexible parts, you must definitely take your printer’s extruder type into account. Choosing the right hardware is one of the most important keys to success in TPU printing.

Which Parts Is TPU Ideal For?

TPU’s flexible structure, impact absorption capability, and abrasion resistance make it indispensable in many practical applications. TPU is preferred across a wide range, from industrial use to everyday life. Here are the most common use cases:

• Protective cases and covers: For impact-prone items such as phones, drones, and car keys, TPU absorbs shock during drops and protects the device.
• Gaskets and sealing elements: TPU provides excellent sealing in covers, boxes, and enclosures that require water and dust resistance.
• Vibration dampening feet and pads: TPU feet are ideal for reducing vibration in machines such as 3D printers, CNC, or sound systems.
• Drone and RC vehicle parts: Parts frequently exposed to impact, such as propeller guards, landing gear, and frame connections, last much longer when made with TPU.
• Wearable accessories: TPU’s hypoallergenic nature is an advantage in products that contact the skin, such as watch bands, glasses arms, and bracelets.

TPU Printing Tips

For successful printing with TPU, a few critical points need attention. Keeping print speed low (20-30 mm/s) and using minimal retraction are key to getting good results. Nozzle temperature should typically be between 220-240°C, and the bed between 40-60°C. Additionally, since TPU is highly prone to moisture absorption, it is recommended to store your filament in a dry environment and dry it before printing. Even though it prints slowly, the resulting flexible and durable parts deliver results worth the wait.

Do you have a flexible part project in TPU? Calculate your instant price and upload your model to learn its cost within seconds. With 17 different material options, including TPU, we offer the most suitable solution for your needs. For more information about flexible part design, check out our TPU and Flexible Filaments guide.