We started off by looking for an affordable pan-tilt mechanism to make a cat laser game. We found this nice model on Thingiverse by Fernando Bueno from 3D Open Hardware and it was a great starting point. The mechanism has 3 parts. We remodeled the top part of the servo and added a small dome with a hole so that the laser diode could fit in it. The other 2 parts we printed as is.
The build details can be found on our blog - https://www.circuito.io/blog/cat-laser/
In the meanwhile, you can see the project on our Youtube channel >> https://youtu.be/XzmFdUfj8iU
The wiring instructions are here >> http://bit.ly/cat-laser-circuit
And the code is on our github repo >> https://github.com/Circuito-io/LaserCat
Home 3d printers tend to be inaccurate, so if the laser doesn’t fit into the hole, you can use a 6mm drill manually to make it a bit bigger. Just make sure that you don’t drill all the way because the end of the hole is a bit more narrow and prevents the laser from popping out of its place.