“Karakuri,” a Japanese word meaning “mechanism” or “how things work,” originally referred to technologies brought to Japan from foreign countries. Nowadays, however, “karakuri” refers to toys that move using simple gears and mechanisms. These karakuri can be made out of the simplest of materials, requiring just paper and glue to construct various mechanisms. Karakuri: How to Make Paper Models that Move by Keisuke Saka describes several types of karakuri and how to make them. One of the models in the book is the “Wild Wild West” model.
In this model, a train on a track rotates in a circle, moving around a station and through a tunnel, as the handle is rotated. This motion is made possible by two gears inside the base of the mechanism. One gear is attached to the handle and rotates as the handle is turned. The other gear is attached to the underside of the rotating platform. The two gears are placed at right angles to each other with the gears interlocking, so that the first gear rotates the second gear, which in turn rotates the platform. The directions for constructing the model are described in the book.