www.geartechnology.com/articles/22213-mind-boggling-gears
Mind-Boggling Gears
January 1, 2016
Square, rectangular, triangular, oval, even fish-shaped - Clayton Boyer's Weird Gears come in every shape except for circular, and they all work. If you're interested in giving them a gander, check out Boyer's Youtube video (just search "weird gears" and it'll be right there
at the top) to see them in motion