This joint is made from wood. Can you guess how it works?
“Impossible Joint”. Still image from YouTube video.
At a first glance, this should be an easy task. But as you could already have noticed, this Shihou Kama Tsugi, or four-way goose neck joint looks the same on all sides of the pictured wooden construction. “Impossible joint”, isn’t it? How is it possible to take it apart, or even to assemble something like this?
There is some “illusion” involved in making of this interesting joinery, and it could easily qualify as geometric puzzle. The following video shows how Shihou Kama Tsugi is made, and how it is put together:
