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Dad's Puzzle

Dad's Puzzle is a sliding block puzzle similar to the popular "Fifteen Puzzle" and an older puzzle called "Klotski". Place the set of movable pieces into the frame in the arrangement shown. Then, without lifting the pieces, slide the various pieces around so you move the large square from the top-left corner to the bottom-left corner. According to what I have read, the minimum number of moves is 59. My family had a wood version of this puzzle many years ago, and it seemed like a good idea to use the 3D printer to make a replacement. I've given the puzzle to each of my children, hoping they will enjoy the challenge of solving it.


The directions file has move-by-move directions to solve the puzzle. Of course, wait to print the solution until you finally give up on solving it all by yourself.

OpenSCAD Notes

The files here are designed to print using a standard Fused Filament Fabrication 3D printer and were tested on a Lulzbot Mini printer.

OpenSCAD is a "parametric" CAD tool. This means you should be able to adjust the final puzzle size to suit you up to the limit of the printer you have. The size can be set to any value your printer can handle. Using size=25 lets the Lulzbot Mini can print a puzzle that is a little bigger than a paperback book, approximately 130mm by 50mm. The "Size 15" makes a good pocket size version of the puzzle.

The main "issue" in this project is providing spacing so the movable blocks slide easily enough. To accomplish that, a one-tenth extra space is added all around. The smaller versions slide well enough, while the largest I printed still didn't have excessive play between the blocks.

Helpful References:

Available Files:

dadspuzzle.scad - includes sections for printing the movable parts, the base and the cover.
dadspuzzle-15-base-move.stl - at this size, the Lulzbot Mini print bed can hold the base and moving parts at the same time (this file)
dadspuzzle-15-cover.stl - prints the cover by itself
dadspuzzle-25-base.stl - prints the base at a near-maximum size for the Lulzbot Mini
dadspuzzle-25-cover.stl - prints the cover for the large puzzle version.
dadspuzzle-25-move.stl - prints the movable puzzle pieces
dadspuzzle-directions.pdf - a short description and the puzzle solution intended to print back to back (two copies on the US-Letter-size page - easy to download if you want the whole package of files all at once.
GPL3 License