Dr. E 127mm TPU Wheels 3D Print Kit for Electric Skateboards(esk8)! Now you can 3d print your own esk8 wheels that are more comfortable than urethane wheels!
How Does 3D printed TPU Tires get grip?
The TPU Wheels features 230 individual treads that are 4mm tall and “flex” into the ground as you ride, the zigzag patterns on the treads “bite” into the ground giving you snow-tire like grip. As the wheel compresses, the treads bite into each other almost like shark teeth. This is part of what gives these wheels better grip than urethane wheels especially for off-road conditions like dirt, grass, and snow. We’ve experimented with various different heights of treads and found 4mm to be perfect and these would take thousands of miles to wear out in normal conditions(without burnouts).
#DrESkateboard #esk8
DrESkateboard.com is located in Songdo, Incheon, South Korea. We are a team of engineers/designers that work on new TPU Wheel designs for electric skateboards(ESK8).
Jungil Lee aka Max Lee is the founder of DrESkateboard.com. He has been skateboarding most of his life and around 2020, he started getting into electric skateboards, his first board being a Boosted Mini S.
In 2021, Max moved to South Korea in order to be closer to his aging father and started a company to make electric skateboards. Due to battery prices being too high during COVID crisis, he decided not to pursue the business.
Around December 2022, Max wanted to make 3D printed wheels for his electric skateboard that could go over snow due to large amount of snow in South Korea. He started with some 100% solid wheel sleeves for his urethane wheels made with 95A TPU material. After that, he started experimenting by adding different tread designs. He figured since urethane wheels didn’t have treads and pneumatic tires did, if he added some good tread designs to his TPU wheels, he could possibly have better traction on 95A TPU material than much softer 74-85A urethane materials.
For a few months, he was designing and testing out wheels that were sitting flat on the ground just like regular urethane wheels or car tires. He experimented with various different infill patterns such as honeycomb and gyroid. He was able to get the wheels to absorb much of the impact and vibrations with this method but at the cost of losing a lot of range. You see, with just one infill pattern such as honeycomb or gyroid, you would end up with either too much infill making the wheels too hard(and would not flex enough) or too little infill making the wheels too soft(run like flat tires). To make the wheels comfortable enough to ride, the center of the wheels would be too soft. Also, treads on flat wheels simply did not have enough traction as only the weight of the rider would be acting on it. Pneumatic air tires work by having air pressure inside the wheel, let’s say around 35 PSI(pounds per inch). But how could he create that kind of pressure in a 3D printed TPU wheel?
That got Max thinking for weeks then it hit him, he could create “artificial pressure” on the wheel by adding a good amount of curve. By doing this, the center of the curve would be pushed down by the rider’s weight and create “articifical pressure”. Now, you would have to dial down amount of infill percentage so the gravity would push the curve down to near flat structure. And for this, he used gyroid pattern which worked perfectly as it absorbs and releases energy in all directions unlike other infill patterns. And this could ONLY be 3D printed due to the complexity of the pattern.
In other words, as the rider sits on the board, the wheels are pushed down by gravity and the gyoid pattern “energizes” the wheels just like springs. As the wheels go round and round, the gyoid pattern “releases” and “energizes” constantly, resembling how air pressure work inside air tires. And boy, it took Max months of trial and error to get the infill numbers right but once he did, he had wheels that would absorb a lot of the impact and vibration just like air tires.
Again, Max still ran into problems of not having very good range, rolling resistance was way too high and He would still end up with wheels that felt like flat tires. After more weeks of thinking, he thought of another method, make different levels of infills/infill patterns. And this final experimentation was a wild success, He got very good rolling resistance, comfort, and also very good range.
The key to making 3D printed wheels that work like air tires is to make the tire sidewalls very hard using a lot of honeycomb infill(such as 42% for my 127mm wheels), using very little infill in the middle of the tire using gyroid(such as 5% for my 127mm wheels), and also have medium level of infill between the sidewalls and the middle(such as 7% for Dr. E 127mm TPU wheels).
Now, these numbers will vary and you will have to experiment with different infill percentage to get your TPU wheels. But once you do, these TPU wheels are just as durable as any urethane wheel, more durable/last longer than any pneumatic air tires, and also puncture proof.
Our Address:
Dr. E Golf Inc.(That’s our official company name as Max is starting another indoor golf facility in 2024)
107, Artcenterdaero 301-410
Yeonsugu, Songdodong, Incheon 22002
South Korea
E-mail: zedomax@gmail.com
