Nearly two years ago, I decided to 3D print a mechanical calculator.

This project is extremely in character for me. I love old technology, and especially mixing old and new technology (like sending digital data via ham radio).

When you want to 3D print something, there are different levels of how sane you can be. The sanest option is to find a design on a site like Printables or Thingiverse that someone else made. Ideally, one that consists of as few parts as possible.