A Spanish team from the University of Navarra, Tecnun, which competes in the annual Formula Student race, has used 3D printing to cut manufacturing time and weight on several parts.
Tecnun has been able to produce extremely complex 3D printed moulds for key race parts such as an intake manifold in just a few hours rather than the three weeks needed for traditionally-manufactured aluminium moulds. This in turn has allowed the team to redesign some parts to make use of carbon fibre, shaving a considerable amount of weight off of parts used for racing.
Tecnun has used a Stratasys Fortus 450mc Production 3D Printer to create moulds for parts like the intake manifold. This is 3D printed in ST-130 sacrificial tooling material, before the carbon fiber composite material is wrapped around the mold. Once cured, the internal sacrificial core is washed away, leaving the final composite part. This is considerably quicker than CNC machining the mould in aluminium.
Javier Aperribay, technical director of Tecnun Motorsport, says that using the ST-130 sacrificial tooling means the intake manifold can be made with carbon fibre, noting: “The superior soluble characteristic of the ST-130 material enables a more complex shape of the intake manifold compared to aluminum molds, removing the need to assemble all the individual components. We can now 3D print moulds for the intake manifold in just five hours, as opposed to the three weeks lead time associated with conventional aluminum moulds.”
He adds: “We find that the material performs in high temperatures of up to 121°C and, at certain temperatures, pressures of up to 620 kPa throughout curing.”