Laser Cut Puzzles

One of my best friends in the world - Brandon - got married in the summer of 2024, and insisted that no gifts would be exchanged. I nagged him ceaslessly on this point, and he eventually relented that only gifts of creative, rather than financial value would be accepted. Game on.

After much deliberation, I decided to make them a puzzle. I’d been looking for the opportunity to learn how to use a laser cutter, and thankfully both Boulder + Denver offer the tools in their library makerspaces. Over the course of several months (and gifts for several close friends - celebrating a wedding, commiserating about the passing of a beloved dog, etc.), I fine tuned both the code for generating the puzzle, and the usage of the laser cutters (trying out three different kinds over time, and finding the right set of controls for each).

In the end I was very impressed by the Glowforge PRO, which consistently had the lowest amount of hassle, and produced consistently good rasters. The Epilog laser I used for the final cut was also quite good both in precision and accuracy in the cut,but the raster left quite a bit to be desired.

The final process I found to be effective involved first etching the image on to the wood in a purely raster pass, and then doing the final cut only once masked with masking tape, which prevented burn scars.

The primary challenge of this project was scooping up the tool appointments at each library as it became available - they were hot commodities and I often needed to plan my days to keep free the half hour when I knew the appointments would go online.

Fine tuning the code was another tricky part, since there were a lot of things to tweak, and very slow iteration cycles for trying them out in the real world. I eventually figured out a structure for the nubs that would cut well, and designed a cool algorithm for making the sides and curves generally smooth, while not doing a full grid like a standard puzzle.

By the end, the code was capable of taking in an internal and external cut, so that hidden shapes could be included in the puzzle. In this test cut you can clearly see the “4” and the heart, a reference to the date of the marriage.

I gave them the final result at their wedding, and they completed it during a subsequent bout of COVID - ultimately framing it on their wall.

(A piece was lost from the leftmost edge - a standard foible of the genre)

This project was a great reminder for me that the best gifts are about the thought behind them and the expression of care for the other people. Building this gave me ample opportunities to reflect on how much both of the people meant to me, and how thankful I was to have the time and skills to tinker.