Use an Arduino Pro Micro to Build a Simple, Single-Key, Bottle Cap Keyboard

Your keyboard is, of course, extremely versatile. Many of us use mice to help navigate the GUI interfaces that are so common today, but experienced users can get around using just a regular old keyboard. That said, it’s sometimes useful to just have a big button dedicated to a single function. Maybe you want that button to start your favorite music playlist, or to launch all of the programs you use for work. Whatever the case, YouTuber fmtuve has a tutorial on how to build a simple, single-key, bottle cap keyboard.

Instead of a traditional key cap, this design uses standard threaded soft drink bottle caps. That’s a unique idea, and allows you to switch between readily-available bottle caps whenever you like. If you want to customize the look, just paint a bottle cap after you enjoy the soda! The bottle cap adapter mounts onto standard mechanical key switches, so you can use whatever model you prefer to get the exact tactile feel you’re looking for.

To follow fmtuve’s guide and build your own bottle cap keyboard, you’ll need the mechanical key switch, an Arduino Pro Micro, a corresponding USB cable, and a 3D printer to make the enclosure and key switch adapter. After printing your parts, assembly is very straightforward. The key switch only requires two wires, and everything else snaps together (though you can use screws if you want it to be as solid as possible). Then just upload fmtuve’s code to the Arduino and set whichever key presses you want the button to send. The code makes the Arduino show up as a standard USB HID device on your computer, so it’ll be plug-and-play.