A solid 3mm metal rod can slide (almost) effortlessly through the block. How can that be?
The mechanism for this puzzle is related to the ancient
Heron's Horse, where the magician slices a sword through the neck of a horse state without the head falling off. However, whereas
Heron's mechanism (see page 109) uses rotors, Oskar's mechanism features meshing gears. The result is a less friction and a smoother cut.
Watch the
YouTube video.
Read at the
Shapeways Forum.
Read more at the
Non-Twisty Puzzles Forum.
Please
contact Oskar directly if you are interested in obtaining a fully colored, stickered and assembled sample of this piece of magic.