Many of you have already asked us how we went about creating our wheels with Cyril, our mentor who is overseeing this project.
Here’s what we can tell you:
We have done several tests with commercially available silicones (in Shore 30A, 45A and 50A / references below)
The Shores 30A and 45A are too soft: wheels launched at full speed deform too much and tend to detach from the axle.
If you want to start making your wheels like we did, here are the instructions.
Be sure to follow the instructions of the products used to work safely.
Step 1/ Create a mold (a negative of the wheel) in 2 parts so that you can easily unmold the wheel. We link you to the STL here https://robolyon.com/wp-content/uploads/2024/01/mold-wheel.zip
You will see, the axle of the wheel has been adjusted (shrunk) to better adhere to the hexagonal axle (variable to be taken into account depending on the silicone used).
Step 2/3D print and sand any rough edges of the 3D printing.
Step 3/ Make sure to remove all the bubbles from the mixture by placing the whole thing under a vacuum chamber (the more bubbles there are, the more there is a loss of density and the risk of breakage and/or deformation of the wheels)
Step 4/ Pour the silicone to the brim into the mold (it is advisable to spray the mold release agent beforehand). Carefully respect the drying time and conditions of the leaflet for the silicone used.
Step 5/Release
We hope you find this tutorial helpful. Give us your feedback and show us your wheels!
Here are the links of the tested silicones:
The 30A too light:
The 45A, still a little too soft:
The 50A, fine:
https://www.siliconecomposite.com/nos-silicones/les-kits/za-50-lt.html
___________________________________________________________
The vacuum pump: