There is no doubt that 3D printing gave us the ability to bring our ideas to life. With its help, creating customized pieces, specific designs, and improving existing products is way more comfortable than ever.
This article is about one of its fantastic projects, 3D printing tires. Before creating a unique tire design, it’s necessary to find the most suitable material for it. So:
What is the best 3D printing filament for tires?
Nowadays, thermoplastic elastomers (TPE) are the best category of filament material for flexible tires. TPE filaments have very similar properties to rubbers which are the most common material for tires. Ninjaflex and Fiberflexare two of the best TPE filament brands.
There is much more information to comprehend before choosing the best filament suited for your work, based on the design and application.
Required Properties for Tires
The basic concept of flexible tires is easy to understand. Cars are groundbreaking inventions that made massive changes to our everyday lives throughout history.
When it comes to car parts, tires are seen firsthand; they are the base of any vehicle, and they’re made out of rubber.
Tires should withstand constant tear, wear, and various ranges of heat and humidity. Hence some of its main tasks are:
Maintaining The Needed Grip
Every vehicle needs to be able to move regularly, no matter how the weather or temperature changes.
Thus, tires have to operate independently of environmental conditions or the road’s material; Rubber helps with the stability of the car and thus holding the grip on slippery roads. This plastic does a great job of keeping the grip and maintaining it, no matter how rough or tough the ground is.
Unfortunately, rubbers are thermosets, which means that once it melts, it will lose its properties and shape. In other words, they can’t be 3D printed.
So, long story short, it’s essential to choose a filament material with the same grip abilities as rubbers. Some TPU filament brands provide good grip properties, though they are not as good as industrial engineered composites.
Having Long Life Span and Fair Price
Every tire continually rubs against the ground and endures considerable pressure. The tires are also exposed to impacts, so they should be excellent absorbers. Price is also another factor, so every designer strives to minimize production costs.
Hence, selecting a material that withstands wear, shock, and pressure is crucial. Filament materials like PLA or ABS won’t tolerate these situations.
In the next section, we will study TPE and TPU flexible filaments, which are more suitable for our purpose.
What is TPE/TPU?
TPU and TPE are two groups of thermoplastic elastomers that have the ability to be printed into flexible products. These 3D printing materials are the most similar filaments to rubbers.
The unique structure of Thermoplastic elastomers results in properties like shock absorption, vibration damping, and outstanding resistance to wearing, high temperatures, and abrasion. These were the features that made rubber the chosen material for tires.
First and foremost, let’s understand the main differences between TPE and TPU:
They are both categories of flexible filaments. TPE stands for thermoplastic elastomer, and it’s a combination of soft rubber and hard plastics. So, the name TPE covers a wide range of flexible thermoplastics. Thermoplastic polyamide, thermoplastic co-polyester, and thermoplastic polyurethane are some subgroups, to name a few.
On the other hand, TPU stands for thermoplastic polyurethane. Nowadays, they are the most popular type of TPE.
TPE is more of a general term, describing all of the loose filaments. It’s also good to know that TPU filaments are on the rigid side of the spectrum.
3D printing a soft, flexible filament is more complicated than hard plastics. TPU filaments have the least flexibility among all, so they are usually easier to print. It is what makes them so popular.
However, there are more fundamental differences.
TPU filaments are heavier and denser than the other TPEs. 3D printed objects out of TPU have smoother surface finishes, while most TPEs are rougher and have rubbery textures. TPU filaments have better abrasion resistance and rigidity.
Hardness is the most important mechanical property of flexible filaments. For materials like rubbers and polymers, this quantity is usually measured by shore hardness. For example, the shore hardness of TPU filaments is mainly in the 60A to 55D.
Lower numbers indicate less resistance to indentation and thus softer materials. In contrast, higher numbers indicate more resistance and more rigid materials.
Now, let’s check out some of the better options:
When it comes to 3D printing elastic objects, NinjaFlex from NinjaTek is one of the options that fit the bill. It provides enough strength and wear resistance and has a proper grip suited for tire materials. With a shore hardness of 85A, NinjaFlex has very similar properties to rubber tires.
There are also lots of positive comments and successful experiences about this brand in the 3D printing communities.
Here you can find information on the physical properties and printing parameters of NinjaFlex.
|Tensile Yield Strength||4 MPa|
|Elongation at Break||%660|
|Impact Strength, Notched||4.2 kJ/m2|
|Abrasion Resistance (10,000 cycles)||0.08 g|
|Melting Point||216o C|
|Extruder Temperature||225 – 235o C|
|Platform Temperature||Room temp – 40o C|
|Recommended Printing Platform||Glue and Blue tape if not using a heated bed|
With a shore hardness of 40D, Fiberflex is an excellent alternative for rubber elements in machinery, such as gaskets, tires, and pieces that frequently bend. This material also has a significant impact, abrasion, and chemical resistance, so it’s very suited to the job.
You can find the mechanical properties and printing conditions in the following table:
|Tensile Yield Strength||44 kg/cm2|
|Elongation at Break||%680|
|Izod Impact Strength / Notched||N.D. kg*cm/cm|
|Abrasion Resistance (10,000 cycles)||0.095 g|
|Melting Point||157o C|
|Extruder Temperature||200 – 220o C|
|Platform Temperature||50 – 70o C|
|Recommended Printing Platform||Glue or Blue tape if not using a heated bed|