May 28, 2021
3D Printing with Flexible Filament TPU - Makenica 3D
There are many materials with flexible properties on the market for 3D Printing services, two types of flexible filament are thermoplastic polyurethane and thermoplastic elastomer.
Although there are many materials with flexible properties on the market for 3D Printing services, the two most common types of flexible filament are thermoplastic polyurethane (TPU) and thermoplastic elastomer (TPE). Both are composed of thermoplastic elastomers, which are a combination of hard plastic and soft rubber.
Although the terminology is often used interchangeably, thermoplastic polyurethane (TPU) is the most widely used flexible material in 3D printing online services.
TPU is a great, long-lasting, flexible filament to have on hand for certain one-of-a-kind projects that require soft or rubbery properties. TPU is available in a variety of colors, as well as consistency and longevity. TPU plastic is widely used in drive belts, phone cases, and footwear.
The degree of flexibility provided by many flexible filaments distinguishes them. Most materials are tested on a “Shore Hardness/Durometer” scale, which measures a material’s resistance to indentation.
The durometer of flexible material is usually denoted as being on the Shore A or Shore D scale. Softer materials, such as flexible filament for 3D printing services, are weighed on the Shore A scale, whereas tougher rubbers are measured on the Shore D scale.
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What is TPU?
To better understand ThermoPlastic Polyurethane (TPU) and its applications, it might be useful to look at its practical predecessor, ThermoPlastic Elastomer (TPE). TPE was the material of choice for lightweight printing materials until a few years ago.
TPE is a kind of plastic with rubber-like properties in 3D Printing in Bangalore. It can be extended to double its original length and then returned to its original shape without permanent deformation.
The softness of the TPE filament, on the other hand, found it tough to deal with. With a shore hardness of just 85A, TPE filaments had a propensity to be improperly treated by extruders that were not made for flexible filaments.
In 3D Printing services, TPU is a newer and more firm version of TPE. TPU has a more outstanding balance of elasticity, rigidity, and stability by incorporating low polarity segments (or flexible segments) and high polarity segments (or heavy segments) into a single polymer strand.
The finished product has a marginally higher shore hardness of 94A, making it simpler to treat with the 3D printing extruder mechanism.
For the first time, printing with TPU filament can be challenging. It is harder to print because of its elastic properties, making it more difficult for the extruder to press through the hot end. Ensure there are no gaps in the path of the filament from the extruder to the hot end. If possible, use a Teflon tube to direct it.
When dealing with flexible filaments in 3D Printing services, it is better to consider using direct extruders. As previously said, the length of pipe that the filament must traverse in a Bowden extruder complicates the method. Working with a Bowden extruder is still possible, but extra fine-tuning of the printer’s settings might be needed to achieve successful performance.
More modern 3D printers that use Bowden extruders have been developed to minimize issues with flexible filaments. If you are confused about your printer’s features, check with the 3D Printing services vendor and see if your model is compatible with flexible filaments.
Extrusion temperatures of 200 to 220 °C are recommended for TPE filaments in 3D Printing in Bangalore. We still advise using a heated bed platform with a temperature range of 80 to 100 °C.
TPE has excellent adhesion properties in 3D Printing services, so surfaces like glass or aluminum should be no concern. We also consider using Kapton Tape or blue painter’s tape for the best performance.
When dealing with lightweight filaments, it is best to print at very slow speeds. Flexible filaments bend and contract when stressed, so printing quickly would most certainly clog your extruder.
A setting of 15mm/s is preferred, but you can print at speeds up to 30mm/s with good performance. This will vary depending on the model you’re using, so start with a low setting and work your way up to see what works.
Since flexible filaments are less resistant to warping during printing, you may use a cooling fan in a medium or high environment. This allows you to keep fine detail on your prints without sagging or sloppy melting. We also suggest not using a cooling fan on the first two layers to ensure excellent bed adhesion.
Retractions are often needed when the design calls for the extruder to travel long distances without printing. On the other hand, retractions can be especially difficult when using flexible filaments because they are vulnerable to rapid movements.
We suggest turning off retraction entirely, mainly if this is your first experience using flexible filaments. If you can’t stop it, you can set a very slow retraction speed or reduce the need for retraction in your design.
Types of flexible TPU
Flexible Thermoplastic Urethanes (TPU) filaments used in 3D printing services vary in Shore A from 60 to 90 and are graded as ultra-flexible to semi-flexible. Depending on the application, there is a flexible filament with the properties needed to satisfy the needs of its users.
The most rigid-flexible filament is a semi-flexible TPU with a Shore A durometer of 90. (90A). This material is perfect for learning how to print flexible filament because its hardness mitigates its shortcomings.
A Shore A 90 material is considered stiff and, depending on the infill, can be printed rigidly while retaining flexible properties. It is an excellent material for when a degree of flexibility is needed while maintaining structural integrity, and it can be successfully printed on a Bowden-type extruder.
The most common flexible filament is a Flexible TPU with a Shore A Durometer of 85 (85A). A Shore A 85 material is considered medium-hard, but it is very lightweight and provides a wide range of flexibility based on infill.
Although an 85A flexible filament can be printed on a Bowden extruder, the steep learning curve necessitates a well-optimized setup. It is suitable for gaskets, grippers, hinges, and RC tyres and accessories.
The most flexible filament in 3D Printing Bangalore is an Ultra-Flexible TPU with a Shore A Durometer of 60. (600A). A Shore A 60 material is graded as medium-soft, but it is highly flexible, even when filled to a high degree.
To print with it, it is strongly advised to use a well-configured direct drive extruder or a Diabase Engineering Flexion Extruder. Overprinted sections (such as rigid modules with integrated gaskets) or soft robots are suitable applications.
What are the advantages of using TPU?
TPU is a material with a distinct set of properties. It has a rubber-like elasticity that sets it apart from the more traditional ABS and PLA. It is also abrasion tolerant and has been shown to perform well at low temperatures.
In 3D Printing Bangalore, TPU has traditionally been used to print items that must rotate or stretch during use, such as athletic goods, medical equipment, footwear, inflatable rafts, handheld device outer covers, and vehicle instrument panels. Because of its resilience to liquids, greases, and several solvents it has also been used in industrial applications.
In 3D Printing Bangalore, TPU is much simpler to deal with than TPE in terms of usability. TPE’s highly flexible nature makes working with it difficult, particularly when using a Bowden extruder.
When using a flexible filament, the length of the tube between the extruder and the hot end adds a level of complexity since the filament can contract inside the tube as the extruder moves it. TPU’s firmer construction eliminates the majority of the issues associated with dealing with TPE filaments.
TPU’s layer-to-layer adhesion is usually excellent due to its extremely soft composition. This means that TPU prints should be highly durable.
| Keep it dry | Where necessary, use a resealable container or a silica gel pad. Most flexible filaments are hygroscopic in some way and can pop and sizzle if extruded wet. There are water pockets that quickly steam up, leaving voids in your print. |
| Changes to spool | For flexible materials, a few changes to your spool holder can also make a huge difference. Mount the spool above the printer so that the filament unwinds downward, which will minimize resistance. If necessary, mount the spool’s hub on a bearing to enable the spool to rotate as freely as possible. |
| Slow it down | To stop binding or wrapping around your extruder gear, TPU should be printed at a much slower speed than ABS or PLA in 3D Printing services. There may be printable files available for your printer to help deter this from occurring. |
| Turn off Retraction | Turn off retraction totally for the whole print. Constant retraction can result in under-extrusion in your print due to pressure being released in your hot end. Retraction also enhances the risk of the filament winding around the extruder gear in the middle of a print. This can result in minor stringing, which can be quickly removed with a lighter. |
| A Large Layer Height | Using a lower layer height significantly increases the likelihood of a clogged nozzle. Increase the layer height to 0.3mm. This will cause the TPU to flow freely and continuously. TPU is perfect because it melts together to form a smooth and solid component even with greater layer heights. |
| Build surface Type and Levelling | In 3D Printing services, TPU filament adheres to most build surfaces. There’s no need for glue or hairspray. Level the bed a little higher than average to prevent the nozzle from dragging over the soft first layers. |
The biggest disadvantage of using flexible filaments such as TPU in 3D Printing in Bangalore is the additional difficulty in handling them during printing. As previously said, not all 3D printers are capable of using flexible filaments.
Bowden extruder printers are especially troublesome. On the other hand, newer versions may have already taken steps to make them more compliant with flexible filaments. TPU’s firmer nature should allow it to be used in a broader range of applications.
TPU can also exhibit weak bridging properties, resulting in prints of many blobs and stringing. To get a decent quality printout of the flexible TPU, you would need to find the “sweet spot” of the combination of printing temperature, printing speed, and retraction speed.
Another disadvantage of using TPU in 3D Printing in India to create prints is that they cannot be completed to achieve a polished and flawless appearance. TPU, unlike PLA or ABS, does not dissolve in basic chemicals such as acetone. TPU printing is very much a case of “what you see is what you get.”
FAQs
TPU stands for Thermoplastic Polyurethane. TPU is a more soft and compact alternative than other 3D printing filaments.
TPU differs from rubber in that it is heated and cooled before being vulcanized, whereas rubber is vulcanized. Rubber, on the other hand, cannot be recycled. As a result, businesses are attempting to discover new applications for old tyres, such as shredding them and using playground material as a substitute for sand.
TPU is used in a variety of areas. It is not a filament as used outside of 3D printing in India. TPU is used to produce phone covers, soft insulating material around cables, drive belts, caster wheels, and various other products.