Everything You Need to Know About TPU Filament
TPU Filament: A Complete Guide: Image Source: allthat3d.com
TPU, the most popular flexible filament, is stretchable, resilient to impacts, and attractive when 3D printed. TPU is a fun 3D printer filament for hobbyist projects and rapid prototyping that produces good-looking flexible objects. In this article, we will explore the information about TPU filament, its advantages and disadvantages, and its applications and uses in 3D printing.
What is TPU?
A member of the family of thermoplastic elastomers, thermoplastic polyurethane (TPU) combines the best qualities of thermoplastics and rubbers (thermosets). Thermoplastic Elastomer, or TPE, is a term that you might be more familiar with. TPE is a very soft, rubber-like plastic that can be twisted or stretched without deforming, and it was once the preferred material for flexible 3D prints. TPE is a particularly difficult material for machine extruders to 3D print because of its softness.
TPU has characteristics similar to rubber, including good tear and abrasion resistance, high elongation at break, and thermal stability. It is also resistant to several chemicals, oils, and greases and it is much simpler to 3D print with and more substantial than TPE.
Advantages and Disadvantages of TPU Filament
Advantages
- Flexible to adapt and soft: TPU is flexible and soft, making it ideal for making elastic parts.
- High-quality vibration and impact dampening: TPU filament's flexibility makes it an excellent material for absorbing shock and reducing vibration.
- Available in a variety of colors: TPU is available in a variety of colors, similar to PLA or ABS, from basic black, grey, and red to clear translucent filaments.
- Minimal warping: This makes it ideal for long, thin parts that might otherwise curl if printed in ABS.
Best for prototypes that can be bent: TPU 3D printing is excellent for testing and bending prototypes. TPU is ideal for functional, flexible prototype testing because it prints more quickly than other flexibles, can withstand a range of temperatures, and is chemically and abrasion-resistant.
Disadvantages
- Normal strings: TPU filament is prone to string, which can be removed rather quickly but is still a headache. This can be avoided by optimizing print settings.
- Challenging to post-process: Sanding and refining TPU's surface polish is known to be challenging. However, recent tests with TPU pieces heated in ovens at high temperatures for brief periods have produced glossier finishes, but proceed with extreme caution.
- Worse for Bowden extruders: When printing with a Bowden extruder, greater caution must be used because the filament is more likely to coil and clog the longer it travels to the hot end.
Applications of TPU
TPU is commonly used in the production of phone and tablet cases. The fact that it can absorb shocks, vibrations, and impacts makes it an excellent material for tires and other bespoke rubber products that function as shock absorbers.
TPU is likewise utilized in 3D printed footwear, particularly in the soles. TPU filaments have been employed in several intriguing 3D-printed shoe projects in addition to PEEK. The caster wheels and those found on chairs, desks, and other equipment like drive belts are occasionally made of TPU.
1) Making 3D Prints Using TPU Filament
Making 3D Prints Using TPU Filament: Image Source: ballisticbit.com
Polyether polyurethane and polyester polyurethane are the two primary types of TPU filament. Each has slightly different properties and is well suited to perform a specific function. By appropriately combining polymers into the TPU material to obtain precise material properties optimized for the intended part, it is feasible to produce a certain hardness. Additional product flexibility can be managed using the part's infill density. TPU does not experience thermal shock warping, which is typical in 3D stiffener 3D prints compared to other 3D print materials.
TPU offers a challenge to 3D printers and necessitates extra care from the user to properly generate a good print, so it's not all sunshine and roses. Prior to printing, it is essential to understand the behavior of the particular material in order to employ the right settings and finish the print.
Bowden drives are unlikely to offer appropriate print performance because of the "stretchy" nature of the TPU within the Bowden feed tube, making the use of a direct drive preferred for ensuring proper print flow. It is conceivable to employ Bowden drives, but only if their path is kept as short as possible to prevent uncontrolled flow to the print head. Due to the inherent flexibility of TPU filament, retraction parameters must be kept to a minimum and optimized. Incorrect retractions, if not handled properly, can leave gaps in the print or even clog the print head.
TPU Prints must be carried out at a low feed rate to ensure consistent flow; otherwise, a sudden change in the feed could become unpredictable and lead to failure. If the part interacts with other rigid parts, it is also crucial to consider employing negative tolerance for correct fit.
5 Tips for Using TPU filaments in 3D printing
1. Printing Temperature: Depending on the 3D printer and TPU filament type, the recommended extrusion temperature range is between 225 and 250°C. However, keep in mind that printing at greater temperatures will let the filament melt more quickly and flow from a nozzle more easily.
2. Extrusion multiplier: The 3D printer's Extrusion Multiplier setting lets you adjust the extrusion flow rate or how much filament emerges from the nozzle. TPU filaments tend to extrude incorrectly throughout printing, leading to poor layer and perimeter bonding. You can solve this problem by slightly raising your extrusion multiplier.
3. Speed: Usually, slower 3D printing speed is ideal for TPU. To guarantee excellent prints, it is a good idea to set the pace at half the average (15 mm/s to 20 mm/s).
4. Retraction: A 3D printer's retractor mechanism pushes the filament backward into the extruder to stop the melted filament from seeping out. This capability is helpful with hard filaments like PLA and ABS; however, retractions with TPU filaments can be difficult and cause blockage. To avoid stretching and compression of the flexible filament in the nozzle, it is therefore strongly advised to turn off retraction.
5. Skirts and rafts: A raft is a temporary horizontal platform on which a printed object is placed to stop warping. However, rafts are not advised when 3D printing with TPU, as TPU pieces typically do not bend. This is not the only reason; fast printing speeds might result in extra printing difficulties. To monitor the filament's flow and guarantee the success of the first few layers, it would be advisable to print a skirt or a few loops of material around the print.
Create Your 3D Models With SelfCAD
SelfCAD is a powerful and easy-to-use 3D modeling software that allows you to create 3D models for 3D printing. With SelfCAD, you can design any model you can imagine, whether simple or complex designs. SelfCAD also offers a wide range of tutorials and support resources to help you get the most out of the software. The software offers various tools that makes the design process simpler. A good example is the freehand 3D drawing and sketching that makes it possible to create designs from scratch. Another important tool in SelfCAD is the image to 3D model that makes it easier to convert images to 3D models. There is also an in-built slicer for generating the G-code, which contains the instructions to your 3D printer on how the design will be 3D printed.
SelfCAD also offers incredible value for your money because it is among the most reasonably priced solutions for 3D printing software. SelfCAD is the ideal 3D modeling program for the job, whether you want to produce simple designs or complex models.
Conclusion
TPU is a material with unique qualities that has a large number of potential uses. However, due to the special characteristics of the material, 3D printing with TPU can be challenging. It is essential to understand the potential and restrictions of TPU before printing. After reading this article, we hope you're well on generating your 3D-printed TPU parts successfully.
Enjoy powerful modeling, rendering, and 3D printing tools without the steep learning curve.
Need to learn 3D modeling? Get started with interactive tutorials.