Printing with TPU: Best practices for flexible success

TPU is one of the most versatile materials available in 3D printing. Known for its flexibility, abrasion resistance, and toughness, TPU enables a wide range of applications - from wearables and seals to custom gaskets and grippy surfaces. But to get the most out of this flexible material, it’s important to understand how it behaves during the printing process and how to optimize your setup.

In this article, we’ll explain what TPU is, where it excels, and share best practices for printing it successfully. Whether you're new to flexible materials or looking to improve your results, this guide will help you get started.

What is TPU?

TPU stands for thermoplastic polyurethane, a flexible, rubber-like polymer that sits within the broader thermoplastic elastomer (TPE) family. Unlike rigid materials like PLA or ABS, TPU offers a unique combination of strength and elasticity, making it ideal for parts that require durability with a soft touch.

Thanks to its ability to bend, stretch, and recover shape, TPU is used in a wide range of functional applications. These include shock-absorbing components, seals, protective covers, orthotics, and parts for consumer electronics and wearables. It’s also valued in automotive and industrial settings for its resistance to abrasion, oil, and chemicals.

One important aspect of TPU is its Shore hardness - a scale that measures how soft or firm the material is. For example, UltiMaker TPU 95A offers a good balance between flexibility and ease of printing, while softer TPUs like Forward AM’s Ultrafuse TPU 85A provide a more rubbery finish, though they may be more challenging to work with.

1. Use a 3D printer with a direct drive extruder

TPU’s flexibility makes it prone to buckling in Bowden-style extruders, where the filament must travel a longer path to reach the hot end. A direct drive extruder offers much more control, reducing the chance of jams and ensuring smooth material flow.

UltiMaker Factor 4 is equipped with a precision-engineered direct drive system, designed to handle even demanding flexible materials like TPU with consistency and reliability. This makes it a strong choice for manufacturers or professionals who need to print TPU parts with accuracy and repeatability.

2. Choose the right TPU (-like) material

There is no one-size-fits-all TPU. The best material depends on the needs of your application. UltiMaker TPU 95A is an excellent all-purpose option, combining durability with manageable flexibility. For more elastic or specialized needs, third-party materials such as Recreus Filaflex 82A or Forward AM TPU 85A offer different performance characteristics. Other suppliers such as ColorFabb’s Varioshore TPU’s offer ‘foaming characteristics’. By varying the foaminess of a filament, you can have greater control of the hardness of TPU. Tectonic’s Anasa TPC provides additional properties, making the filament partially bio-based.

With UltiMaker, you’re not limited to a proprietary ecosystem. The open filament system allows you to choose the material that best suits your application. You can print with UltiMaker-certified filaments or select high-performance third-party materials, giving you the freedom to tailor your prints to the job at hand. If you are using a dual-extrusion printer, such as UltiMaker Factor 4 or S-series, you are not only limited to one material. With dual extrusion, you can innovate simultaneously with TPU and other materials.

3. Slow down the print speed

One of the most common causes of poor TPU print quality is printing too fast. Slowing your print speed to between 20 and 30 mm/s helps maintain consistent extrusion and prevents issues like stringing, under-extrusion, or loss of detail. TPU needs time to flow smoothly through the nozzle due to its elasticity, so resist the urge to push speeds as you would with PLA.

4. Optimize temperature settings

TPU is sensitive to temperature, and dialing in the right settings is key. A nozzle temperature between 220 and 240 °C is a good starting point, depending on the specific brand and Shore hardness of the TPU. Bed temperature should be set between 40 and 60 °C to help with adhesion.

If you’re using UltiMaker’s Digital Factory and Material Marketplace, you can easily access pre-configured print profiles for UltiMaker TPU 95A and many third-party materials. These profiles ensure optimal temperature, speed, and retraction settings are loaded automatically, saving time and reducing trial and error.

5. Keep TPU dry before printing

TPU is hygroscopic, meaning it absorbs moisture from the air. Even a slightly damp spool can cause print quality issues such as stringing, bubbling, and inconsistent extrusion. To avoid this, make sure your filament is properly dried—ideally using a filament dryer or by placing it in a low-temperature oven at 40–50 °C for a few hours.

The UltiMaker Factor 4 comes equipped with a built-in Material Station that stores up to six spools of filament in a humidity-controlled environment. If you are using UltiMaker S-series, you can choose for example the S8 Pro Bundle to get access to the Material Station. This helps protect sensitive materials like TPU from moisture exposure and ensures they’re ready to print when you are.

Innovate flexible applications with UltiMaker

TPU is a powerful material that brings flexibility, durability, and functional performance to 3D printing. Whether you’re prototyping wearable tech, producing end-use parts, or exploring industrial applications, TPU allows you to go beyond the limits of rigid plastics. By following best practices - selecting the right printer, material, and settings - you’ll unlock the full potential of this unique material.

UltiMaker Factor 4, with its direct drive extruder, open filament system, and integrated Material Station, provides everything you need to print even softer TPUs with confidence. Combine it with Digital Factory for instant access to tested material profiles, and you’ll be set up for success from the first layer onward.