Here’s a small project featuring what I think is a really nifty snap-lock design for laser cut assemblies. I used it when making dorky headgear for Bay Area Maker Faire 2019.
I definitely didn’t come up with this snap-lock mechanism myself. In fact I saw it years ago on the Machines That Make (MtM) project from the MIT Media lab when researching little DIY CNC project. I liked it so much that it always stuck with me.
The MtM snap locks are cut on thick sheets of plastic using a CNC router, so the parts naturally create stiff square joints. This is less feasible on a laser cutter given the slight draft on all cut edges, but we can overcome this easily by just using two layers of snap lock features, essentially creating a little box structure. While the snap-lock quality is almost certainly superior with the CNC routed parts featured on MtM, the laser cut parts are still pretty nice, and its hard to argue with how fast the process is.
The propeller is also laser cut flat sheet and then just bent by hand, no heat needed even. The “worm gear” is some welding wire bent around a metal rod, which is how I got such consistent “threads.”
If you are interested in making your own silly head gear, or modifying these files for your own design, feel free to download the STEP files below:
Here’s a quick video of how all these parts go together: