October 18, 2025
Description
A difficult ball pyramid puzzle by Leonard Gordon. It was actually invented before 1980 by his brother Jerry Gordon. The Gordon Brothers started making this puzzle from clear polystyrene (see photos) and from 1984 to 2018 it was sold by Kadon Enterprises. You can read more about the history of this puzzle here. In 2019 Kadon ran out of parts and you can no longer purchase this puzzle, but now you can print one yourself. If you like the clear look I suggest watching Ebay for used copies.
This is one of the most difficult ball-pyramid puzzles. In the original puzzle the solving time is given as "one hour to a year, or more." The final shape is a tetrahedron with 5 balls along an edge. There are 9 pieces and 35 balls in total. There is only one solution! I wrote a document about this puzzle (including the solution) which can be downloaded from this page.
Printer Brand:
Prusa
Printer:
i3 MK3
Rafts:
No
Supports:
No
Resolution:
0.15 mm
Infill:
15%
Notes:
There are nine pieces plus the base plate, the ball diameter is 20 mm. You need four L4's plus one of each of the other five pieces (C4, J4, N4, P4, I3). Each piece has been cut in half for easy printing. Print each half PLUS the mirror image of each half (to make the bottom of each piece). To save space I do not include a separate stl file for the mirror image. You need to do this yourself using your slicing program or any 3D editor. For the L4 piece you will need four copies plus four mirror images. The mirror image of C4 and I3 is the same so it is not necessary to take the mirror image of these halves. Print a total of 18 halves plus the base plate.
The halves are then glued together with superglue. Each half contains holes for alignment. After cleaning the holes out (if necessary) take a scrap piece of 1.75 mm filament. Insert the filament into a hole and cut it off such that about 3 mm is sticking out. After each hole has a piece of filament, fit the other half in place. If the fit looks good, remove and glue the halves together.
Category: PuzzlesLicense:
Creative Commons — Attribution — Noncommercial
G Bell
