Hand Wired Split Keyboard

The split keyboard project was the outcome of boredom due to the strict Covid-19 lockdown restrictions in Ontario combined with the desire to create something. I went through multiple design stages and key layouts before settling with the split 75% layout.

The final design has a standard QWERTY layout with arrow keys and a custom column of keys on the right. There is a split line near the center of the keyboard where the two halves can come apart. The purpose of the split design is to provide me more space for my mouse while gaming. The left half can function on it’s own or together with the right half. The two halves can also be connected with a USB-C to USB-C cable so that the entire keyboard can be used while split apart. To improve ergonomics I designed the keyboard to be very thin.

The most challenging aspect of the design was the split line between the two halves. The two halves of the keyboard have multiple interfacing surfaces which lead to a tolerance stack up. I printed multiple truncated versions of the two halves to test fit the interfaces with different clearances. Once I was satisfied I printed the full halves and began assembling and soldering.

The keyboard is powered by two teensy 2.0 microcontroller - one on each side. They both run on custom QMK firmware and communicate with a serial connection. Each switch is connected to a diode and are wired into a matrix which is then connected to the pins of the microcontroller.

The two halves are mechanically held together with magnets and are electrically connected with pogo pins

My future plan for this keyboard is to design a custom PCB replace the soldered wires.