TPU Material 3D Printing -
Tips and Tricks
Thermoplastic Polyurethane (TPU) is a flexible, abrasion resistant thermoplastic that is used in a number of manufacturing processes for both consumer and industrial use. In certain blends it can become very soft, but TPU material offers many benefits and features. When it comes to 3D printing, TPU 3D printed parts are durable and have the ability to withstand ambient temperatures of up to 80 degrees Celsius.
TPU filament is abrasion resistant, can withstand impacts and is resistant to many chemicals. Its versatile and used in many different industries. There are different versions of TPU material but in the main it can be classed as two types known as Polyether Polyurethane and Polyester Polyurethane, with both having different characteristics that can be suited to a specific need.
Impact strength: high
Flexibility: very high
Chemical resistance: medium-high
Abrasion resistance: high
Water resistance: medium
Nozzle/ extruder: 220-250 degrees Celsius
Heated bed: 0-60 degrees Celsius
Closed chamber: Not necessary
TPU is more difficult to print compared to other filament materials, mainly due to its flexibility.
TPU material 3D printing tips
When it comes to printing with TPU filament, it is important to understand its strengths and weaknesses. How do you get the most out of this material? It is vital to take possible issues into account when deciding to start with TPU material, so you know what to expect.
1. Optimising the feed rate
It is often best to use a consistent feed rate that is slow when 3D printing with flexible filaments. This is down to the fact that the material is elastic and can become uncontrollable if there are any sudden changes to the speed of the print. Increased print speeds can result in a compression of the filament, which can lead to a jam. It can often take several attempts to find the optimal print speed for 3D printing TPU material, however, a good starting point is a speed of 35 mm/s.
To achieve this using TPU material, print at lower layer heights, ensuring they are in the range of 0.1mm to 0.2mm. At the lower layer height, there is a requirement for less plastic and that means that the extruder feeds at a lower rate which eases the burden on the filament.
2. Use a negative tolerance and avoid using rafts
When designing a part that is flexible and has a requirement to fit on top of another object, it is worth considering using a negative tolerance between the parts. This will ensure that the flexible part has the ability to stretch comfortably over the other object.
When using flexible filament such as TPU material, it is important to avoid using rafts because the base layers of the rate have a higher rate of extrusion which could lead to problems.
3. Optimize the retraction settings
Because TPU material is flexible and elastic, it makes it very sensitive to fast movements such as retractions. Therefore, to successful 3D print using the TPU filament, it is crucial that you optimise the retraction settings to limit the movements. Its crucial to begin with a small amount of retraction while using a slower speed to help with any possible oozing from the extruder (hot-end).
4. Shorten the distance
The general opinion is in favor of 3D printing flexible materials with a Direct Drive extruder. Nevertheless, you can reach the same results when using the right settings on a 3D printer with Bowden extruder. It is important for the path in which the filament travels to the melt zone to have tight tolerances, which can prevent any kinking or coiling.
5. Placement of the spool
When it comes to 3D printing TPU, a couple of tweaks to the spool of the material can make a large difference. Commonly, the extruder drive wheel will pull the filament into the nozzle, which results in the filament spool unwinding a small amount of plastic in the process. However, as TPU is elastic, the filament will be stretched while pulled which can lead to under-extrusion. Therefore, mount the spool above the printer so the filament unwinds downwards which can reduce any resistance.
Industries that use TPU material in 3D Printing
There are many different industries that use TPU 3D printing because its features offer them a number of advantages.
Sporting goods and footwear
As sporting goods need to be flexible and hard wearing, TPU material is the perfect choice. In many sports it can be found in training aids, water equipment and fitness equipment. Footwear has to withstand low temperatures, flexibility and be resistant to water and chemicals. Therefore, 3D printing TPU is great for manufacturing sporting goods.
SLEM researched the possibilities of 3D printed footwear
SLEM, an innovation and education centre for the footwear industry, has asked Tractus3D to cooperate in a 3D printing project for shoes. The goal is to research how the amount of material waste can be reduced as much as possible, while exploring new and existing methods for rapid customization of digital models for every customer.
SLEM found out that FDM technology and other approaches like Fused Filament Fabrication (FFF) production arguably represent the most cost-effective solution for customizing soles. Shoes created using these processes are particularly effective in tailoring sole designs to the unique needs of wearers, from shape and comfort to gain and specific applications like sports. The ultimate goal for shoe companies in the future will be getting the soles printed within a day to ensure a quick turnaround from receiving customer data to design optimization, production, and delivery to customers.
The aerospace industry is also taking the use of TPU 3D printing seriously as it too has increased its use, understanding exactly what it has to offer. It can also be found in instrument panels and sensors.
The automotive industry has turned to TPU material and implemented it into the manufacturing process of vehicles. In recent years the use has risen considerably and so, it can often be found in instrument panels, sensors and levers as well as many other areas.
What do you want to create by 3D printing with TPU?
By now you understand TPU's strengths and weaknesses. Of course it is vital to choose a 3D printing machine that is able to get the best out of this material.
Create small and detailed parts
With a 3D printer on your desk you can easily create small parts and specialized tools yourself. It is far less complex than other machines, which means that you can produce more products in an efficient and simple way without the high costs. The 3D printers in our desk-series have a fast printing speed, a high accuracy and a low weight, making it easy to put on your desktop or move around.
Create strong and light weight parts
High-performance materials, like PEEK and ULTEM® (PEI) are stronger and more resistant than other thermoplastics, making them popular in a number of engineering applications. To 3D print such materials, you need a special printer that can handle very high temperatures. The High Temperature printers are designed for 3D printing high performance thermoplastics, which are strong and durable for long-lasting parts.
Create large parts up to 2,1 meters
The ability to use 3D printing to enhance business operations, reduce costs and improve efficiency is exactly why a 3D printer has become a popular solution. If you’re looking for a way to produce detailed and big objects our large volume 3D printers are an excellent choice. They have a much larger build size than most other industrial 3D printers and can print objects fast at a high resolution.
Tractus3D printers are all capable of printing with TPU and over 20 other different materials
✓ Most advanced ✓ Competitively priced ✓ You are always covered
Prototypes and inventions
When choosing to start TPU 3D printing, there are a number of advantages and features that can prove to be beneficial. TPU material has already become extremely popular in prototypes and inventions within the 3D printing industry. It is now making it possible for manufacturers to change their approach to manufacturing and so its influence on the industry is rather impressive.
Quality and efficiency
Our industrial 3D printers stand out from the competition because they can handle potential problems that can arise from printing with TPU. For example the High Temperature Printers are designed to handle temperatures which are even higher than required for TPU. It can reach a temperature of as much as 450 degrees Celsius and that puts it ahead of other 3D printers of which many would suffer with internal burning.
Level of accuracy
With this printer, there is an exceptional level of accuracy and speed because of the extreme temperatures that can be reached within the nozzle of 450 degrees. This makes it possible to create objects of the highest quality without errors, using TPU in the way that it is intended. There are also other filaments available and not just TPU, including PLA, ABS, PEEK, PEI/ Ultem™, POM and many more.