Razor Planetary Gear Fidget in Reverse: a revisit of a recent post featuring a planetary gear train with non-circular gears. Using a simple jig that holds the planetary gears in place (but allows their rotation) the system can be used as a transmission into reverse motion of the drive train, turn the inner or outer gear and the other goes in the opposite direction. This piece of kinetic art features a 6-sided sun gear, six 3-sided planetary gears, all held within the 12-sided space of the annula