I'm building a Giant RGB LED cube using ping pong balls as diffusers.
The cube is made up of pillars of eight ping pong balls (each with a NeoPixel LED underneath it) skewered by three wires to provide power and data. To ensure consistency and proper alignment of the ping pong balls, I designed this jig in Fusion360. Using the parameterized design, I was able to quickly tweak it to fit the ping pong ball perfectly. 3D printing is awesome!