The Monkey's Nuts

The Monkeys' Nuts! 1 Bolt. 2 Nuts. 2 Directions. How does it work?

A large heavy brass bolt, with two nuts threaded on it. But all is not as it seems this is a fine piece of mechanical engineering that really makes this bolt very, very special. To remove one nut turn it clockwise. To remove the other turn it counter-clockwise. If you hold the two nuts and rotate the bolt they each move in different directions. Seemingly impossible as the bolt has the same thread along it's length. This is an impossible object, not so much a puzzle to solve, but one to ponder on how it was made.

The Monkeys' Nuts! is, of course, our take on Scott Eliott's Its' Nuts design originally 3D printed by Scott on his SD300 3D Printer. Our version is a very heavy solid brass bolt. (The bolt and two nuts weigh about 1 lb or 440g. The bolt is 7 cm, the shaft around 22mm in diameter.) This thing is big!