Harmonica Marble Slide Puzzle

thingiverse

This is the Harmonica marble slide puzzle, based off a design by Clever Toys. As I couldn't find much information on this puzzle, I decided to design it and try it out myself. However, since there isn't even a picture showing the full range of movement of the original puzzle, this might not be entirely accurate to that original. I had to guess. Besides printed parts, you'll need marbles just under 15 mm in diameter. I used some from an old Chinese Checkers set from a thrift store. You may also want a couple of screws to secure the back panel with rather than glue, so you can disassemble the puzzle if it becomes necessary. Print one top and one bottom piece, as well as one panel, and two pins. Orientation on the two halves is up to you. Pick the orientation with least overhangs, and the curved edges will end up looking ugly. Print with some supports, and you may need to sand them to get them to slide smoothly. Either way, a 0.2 mm tolerance is built in to the dovetail channel. After playing with this puzzle, I have come to the conclusion that it is impossible to solve using only slides and tilts (correct me if I'm wrong). Without a copy of the original, I can't say whether or not this was the intent, but one cannot retrieve the marble from one of the side holes without placing a marble in the other one. So it is necessary to use your finger to perform a pushing move at least once even if you only shuffle it with tilt and shift moves. Placing an extra fourth color of marble in one of the side holes eliminates this issue, but also makes it a more restrictive shuffle. However, I'll let you determine your own rules of play. I have added an alternative pin as well as a stopper file. With these, you can create a couple of other ranges of movement within the puzzle.