From Wind Tunnel to Race Day: Casting Materials in Motorsport
Motorsport and BJB Materials Mini Guide
Motorsport runs on iteration with constant testing, development, innovation and replacements required.
Behind every test and part is a mould, a material and a deadline which would be a struggle to meet without silicones, polyurethanes and foams. This article walks through where BJB Materials Europe fits across race car development from composite tooling to patterns and prototyping.
Why casting materials matter in motorsport
Metal tooling is accurate and durable but it’s slow and expensive. Casting materials offer a soft tooling method which allows for parts to be made in a matter of hours rather than weeks and repeated as often as needed. That speed suits a sport where speed is everything.
Budget is a factor too with the rising F1 cost cap and similar regulations across the racing world. Faster, cheaper development methods mean more budget can go on performance and people. Student racing teams and engineers face a similar issue.
Motorsport Challenges
- Cost cap restrictions or university funds
- Varied and extreme temperatures
- Excessive force and impact
- Intense vibrations
- FIA regulations
- Hour long races
- Non-stop progress
Development and Wind Tunnel Parts
Teams test constantly in the wind tunnel and on the track and require seals, grommets, gaskets and small components quickly. A popular route is using a silicone mould taken from a master, often 3D printed, then casting polyurethane into it. Sometimes these moulds are eggshell moulds instead, meaning they are broken away to release the part.
BJB’s F-1 series of castable polyurethanes span from 5 to 95 Show A hardness, so one mould can produce parts which are soft, firmer, or near rigid by just changing the grade. Urethane pigments also let teams colour code variants in the mould, speeding up production.
Composite Moulding
Carbon fibre wings and fins are often made in one piece inside a closed metal mould. Shaped silicone blocks called intensifies are then needed to press the carbon tightly against the mould. When the mould is heated the silicone expands squeezing the carbon layers together.
Intensifiers can be from liquid silicone in 3D printed moulds. BJB’s platinum silicones fer varied hardness, allowing teams to find the right firmness for their own intensifiers.
Bump Stops and Bushes
A bump stop is a block that stops the suspension hitting metal on metal. Polyurethane bump stops are widely used on lowered cars.
BJB’s F-1 range offers firmer polyurethanes for prototyping allowing engineers to test out different hardnesses and shapes quickly.
High Heat and Fire-Retardant Parts
Engine bays and cockpits are hot, and fire is a real risk. BJB’s F-164 FR is a polyurethane elastomer which meets UL 94 V-2 and has self-extinguishing properties making it suitable for covers and trims.
For under the hood and engine adjacent components, TC-895 offers an extremely high heat deflection temperature (171.1°C).
Padding and Seats
For prototyping padding and test pieces. TC-284 is a two-component flexible foam that forms its own tough outer skin with a similar feel to a car armrest. Expanding foams are also used for custom driver fitted seat inserts. However, regulations and technical data should always be checked for any use outside of testing.
Patterns
Before a carbon body panel is made, the shape it’ll be mould from needs to be created (the pattern). Polyurethane foam is a popular choice for pattern making because it’s easy to shape. BJB’s TC-300 rigid foam can be sanded, stapled and painted soon after demoulding making it suitable for cast-to-shape patterns.
Casting and 3D printing
Almost all the above applications are faster with the addition of 3D printing. Print a master, make a silicone mould, and cast polyurethane into it. You can read more about 3D printing, polyurethane and automotive applications here.
Why racing teams use BJB
- Economical solutions to fit the cost cap
- Speed up production with silicone moulds
- Range of pigments to suit need
- REACH/RoHS compliant products
- Non-mercury and phthalate free products
- Fire retardant polyurethanes
- ISO certified company
- More material options via sister companies to solve all your application needs
Products to Consider
TC-891 Rigid ABS like high-performance polyurethane cast system
TC-895 High temperature polyurethane
TC-300 Rigid Polyurethane Foam
F-164 FR Fire Retardant Polyurethane Elastomer
TC-278 FR Fire Retardant Flexible Foam
TC-5015 Platinum Curing Translucent Silicone Rubber
