The Gakken Cross Copter EX has two contra-rotating rotors, driven by one small electric motor that’s connected via a cord to the hand-powered generator. Build one of three different configurations, or try one of your own!
Easy to build — instructions are in Japanese but feature highly detailed assembly pictures (sorry, no English translation at this time). MAKE is proud to be the exclusive distributor in North America for these brilliant kits from Gakken.
Note: The original video is 45 seconds long….YouTube seemed to add a second just to make us look silly!