Half-Hour - Assembly puzzle by Stewart Coffin (STC #29)

prusaprinters

<h3>Half-Hour</h3><h4>Assembly puzzle by Stewart Coffin (STC #29)</h4><p>Assemble the six pieces to form a 3x3x3 cube. This seems like a straightforward puzzle, but it's harder than it looks!</p><p>Coffin called this puzzle "Half-Hour" because it can reasonably be expected to take half an hour to solve. I confess that it took me longer than that. In coffin's words:</p><p>"As the reader can probably tell, I sometimes run out of names faster than ideas. Some solve this easy looking puzzle quickly and are apt to question the name, but others take a lot longer and question it for the opposite reason. ... It has only one solution. It was the culmination of quite an exhaustive investigation into the near countless number of possible designs."</p><p>Coffin also provided a number of other shapes that can be made with the same set of pieces; several of them are shown in one of the images, which originally appeared in Coffin's book AP-ART. If you solve the cube assembly too quickly, you might enjoy some of these other challenges.</p><h4>Printing instructions</h4><p>Print either <code>coffin.half-hour.pieces.stl</code> <i>or</i> <code>coffin.half-hour.pieces-smaller.stl</code>. I prefer the larger version, but the smaller one will use around 1/3 less material. Optionally, you may also print a box to hold the pieces in place in their solved state when not in use (as shown in the cover photo) - be sure to use the box model whose size matches the pieces you print.</p><h4>The Printable Puzzle Project</h4><p>The <a href="https://www.puzzlehub.org/ppp">Printable Puzzle Project</a> aims to make available high-quality open-source models of many puzzle designs. All of our models are posted with the generous permission of their designers and are licensed for <strong>non-commercial use only</strong>. Anyone may print copies for their own personal use, but selling or otherwise monetizing them is not permitted, and puzzle designers retain all rights as copyright holders of their work.</p><p>Our puzzles are modeled using the open-source <a href="https://www.puzzlehub.org/puzzlecad">puzzlecad</a> library. The <code>.scad</code> file is included with this model in case you want to modify any of its design parameters; more information on how to do this can be found in the PPP <a href="https://www.puzzlehub.org/tutorials/puzzle-modeling">Puzzle Modeling tutorial</a>.</p><h4>About the Designer</h4><p>Stewart Coffin has been called "the most outstanding designer and maker of interlocking puzzles that the world has ever seen". He is credited with over four hundred designs, has pioneered numerous ingenious puzzle forms, and has written extensively about puzzle design and craftsmanship. More information on Coffin, along with many other printable models of his designs, can be found on the <a href="https://www.puzzlehub.org/puzzles/stewart-coffin">Stewart Coffin Puzzles</a> overview page.</p><p>Happy puzzling!</p>