Engine Maker Uses 3D Metal Printing to Optimize Cylinder Redesign

Founded in 1993, the Cobra family of companies in Hillsdale, Mich., designs, develops, and manufactures roughly 2,000 propulsion systems every year for specialty markets including racing, firefighting, aerospace, and underwater vehicles.

To optimize the performance of an engine for a fixed-wing unmanned aerial vehicle (UAV), Cobra Aero decided to visit a Renishaw Inc. (West Dundee, IL) Additive Manufacturing Solutions Center to see how additive manufacturing could save time on cylinder redesign. Using Renishaw’s AM 400 laser powder bed fusion (PBF) machine, the company produced a part with complex lattice structures that performs better than a conventionally manufactured part.

The successor to the AM250, the AM 400 creates a vacuum before backfilling with high-purity argon gas, ensuring a high-quality build environment and minimizing argon use. Suitable for all qualified metals including titanium and aluminum, the machine enables material types to be easily interchanged.

An external powder hopper with valve interlocks allows additional material to be added while the process is running. The hopper can be removed for cleaning or to exchange with a secondary hopper for material change using the universal silo lift. The powder overflow containers are outside the chamber and have isolation valves so unused material can be sieved and reintroduced to the process via the hopper while the system is running.

The AM 400 also includes a larger filter, improved optical control software, revised gas flow and window protection system, PlusPac upgrade, and a new optical system that provides a reduced beam diameter of 70 µm. System build volume is 250 mm by 250 mm by 300 mm.

After completing the project with Renishaw, Cobra Aero bought an AM 400 to expand in-house additive manufacturing capabilities.

www.renishaw.com