Goldberg Puzzle

George W. Hart

Other Puzzles



This puzzle is a 5-inch diameter spherical jig-saw based on a Goldberg polyhedron. I chose the (5,3) polyhedron, which has 492 faces, which is divisible by 12, so it can be divided into twelve congruent sets of faces.




These are its twelve parts.  Each ontains one pentagon surrounded by 40 hexagons. Because these parts are identical, it is not a difficult puzzle conceptually.  But it is still fun to manually assemble.  I was mostly testing the concept, to make sure everything stays together with friction alone. Future variations on the concept may have different edge shapes, which would be more difficult to solve.




Here they are again, this time in a stack, which is how I built them in the rapid prototyping machine.




And here's the puzzle with all but one piece put together. At this stage it is a bit tricky to get the final part in place because there is nothing to push against.  I do it with the aid of a long bamboo skewer that I insert through holes in the other side.