Somewhere around middle-school, I came across a diagram of the classic three-piece burr puzzle.
It looked fun, so I endeavored to make one. Unfortunately, the materials available to me then (a scrap of plywood and a janky power scroll saw) didn’t produce very good results. It worked, but was crude and wobbly. Spray painting it black didn’t help.
A couple years ago, I revisited the project, this time with 3D printing.
Printed at Shapeways in dyed plastic, it works great. It’s kind of pricey though, running just over $90 for the three solid pieces. Similar puzzles retail for less than $5. I tried making hollow versions to lower the price, but it reduced it less than 20%, and required annoying holes to drain the trapped material.
Yes, I could just have bought one. But there’s something fun about precisely realizing something you envisioned decades ago.