The Simply Impossible Puzzle

thingiverse

This is a deceptively difficult puzzle to solve. A quick look and you will think this thing belongs in the kids section of the toy store -- a three-year-old would have a great time with this ... then you pick it up and begin to play ... Whoa! It turns out this puzzle is difficult. Quite difficult! The pieces don't fit together the way you think they might. Give it a try. It's fun! You will need to print four pieces to make the puzzle. I prefer to print them one at a time switching filament for better color. ##Fusion 360 I documented the Fusion 360 steps (along with solve-it spoilers) on Instructables here: https://www.instructables.com/The-Simply-Impossible-Puzzle/ I also attached the Fusion 360 file so you can customize it however you like. My design has a 23mm circle at the top and 20mm at the bottom to form the tab. There is a 0.75 spacing between the tab of one piece and the blank of the neighboring piece. I did not experiment with the circle diameters but I did experiment with the gap. The smaller the gap the harder the puzzle: - 1.0mm gap is a bit too big. It feels loose after the puzzle is together. Also: if you push hard enough, you can actually "cheat" and push the big end of the tab all the way through the small end of the blank. - 0.75 gap works well for me. - 0.5 is solvable but takes a bit too much effort to put it together. - You should avoid anything less than 0.5mm gap. It will be unsolvable. I'd love to hear if someone adjusts the design and tries 0.6mm gap. That might be good too! I'd love to hear if you try different shapes like an oval instead of a circle.