A Three-Key Macro Keyboard with 3D-Printed Switches
"I like to think of this keypad as a '3%' keyboard, it's fine as long as you only want to type 'jes.'"
When we last left James Stanley’s 3D-printed keyboard project, he’d managed to make a switch that lasted for nearly 14,000 actions, along with a custom tester that meant he didn’t have to push it over, and over, and over… and over. As impressive as this is, such operation could still mean failure in a matter of hours of intense keyboard use.
Now, however, he’s created a switch that lasts for 250,000 presses — a number which could have been higher, save for the fact that the testing machine itself failed. While he's still not quite ready to commit to a full keyboard, Stanley has now made a three-key macro pad using this design.
The video below demonstrates it typing out j, e, and s over and over. Though one could simply use a keyboard for these particular letters, since it uses an “Arduino” Pro Micro board, these keys could correspond to any sort of keyboard input, including for media control. Switches are printed in translucent PETG, with the caps done in Prusament Galaxy Black PLA. Caps feature an embossed effect for each letter, which is a nice touch
For the switches, Stanley is using printed spiral spring design to keep the caps aloft. A leaf spring on the bottom that connects two copper wires together when pressed to complete a circuit. You can see it at work in the second video, and much more information on the build and testing method is available in his blog post. We’ll be interested to see how things continue to progress, hopefully into a full-fledged keyboard!