Here’s an interesting problem that no one has cracked. There are no small keyboards that are completely configurable. Yes, you have some Blackberry keyboards connected to an Arduino, but you’re stuck with the key layout. You could get one of those Xbox controller chat pads, but again, you’re stuck with the keyboard layout they gave you. No, the right solution to building small and cheap keyboards is to make your own, and [David Boucher] has the best one yet.
The Thumb Keyboard uses standard through-hole 4mm tact switches on a 10×4 grid, wired up in a row/column matrix. Yes, this is a mechanical keyboard, which is important: no one wants those terrible rubber dome keyswitches, and you need only look at the RGB gaming keyboard market for evidence of that. These tact switches fit into a standard perfboard, allowing anyone to build this at home with a soldering iron. After wiring up the keyboard and connecting it to an Arduino, [David] had a working keyboard.
There’s a lot going on with this build, not the least of which is the custom, 3D printed bezel for those tiny, tiny tact switches. This is a much simpler solution than building an entirely new PCB, which we’ve seen before. Since this is a 3D printed bezel, it’s easy to put labels or whatnot above the keys, or potentially print buttons. It’s great work, and one of the best small keyboards we could imagine.