Recently I made a batch of whirligig propeller hubs for my father. A whirligig propeller hub rotates on an axle and firmly holds the propeller blades. The particular hubs I made for my father are for making yard decorations such as birds with alternately spinning wings. My father easily creates the rest of the whirligig with properly tuned hubs in his possession.
Technical details fresh in my memory encouraged me to prototype whirligigs of my own design. With hard drive storage becoming more affordably available I figured I would recycle my old CDs and DVD into propeller blades. The data patterns on discs distort light in colorful and playful ways. This is the first prototype, once the disc whirligig functions to my satisfaction I intend on selling easy to build kits.