The device comprises a chassis and a rotor. The chassis consists of two circular plywood disks which are connected via three threaded bars. The distance between the disks is 120 mm. In the middle there are two ball bearings and the shaft. For the shaft also a threaded bar is used. The shaft is driven by an electric motor via two crown gears and a toothed belt. The rotation speed is up to 25 RPM.
Complete project here at hackster.io.