wireframe2和時計 (wadokei) are mechanical clocks telling the traditional Japanese time. Unlike elsewhere, Japan maintained a unique time system that measured day time from sunrise to sunset and night time from sunset to sunrise, splitting both periods into six units. This system created a real challenge for clockmakers. For one, the six night time units are much shorter than their daytime equivalents. Further, daylight hours vary over the year, becoming longer in summer and shorter in winter. This required a weight adjustment, done twice a month.

Foliot clocks are known in Europe since the middle ages, and were popular until the superior pendulum design took over from the 17 century. Brought to Japan by Jesuit missionaries and Dutch merchants, local craftsmen adapted European clock design to Japanese needs, adding a second foliot. This addressed the need for different clock speeds during daytime and night time.

On first glance, the face of a Japanese clock with 12 sections looks similar to European eyes. On closer inspection, it quickly turns out that 12 midnight is at the bottom, while 12 noon is at the top. Both are labeled as 9. There are no units numbered 1-3, the system starts with 4. The time units are also named after animals from the Japanese zodiac, midnight is the hour of the rat.

This model of a double foliot Japanese clock was constructed and rendered in Cinema 4D. It was build after real parts from the educational kit produced by Gakken in 2010. Klick to enlarge.