My first self-built computer keyboard - the Gamma Omega TC36K

This week I finished my first self-built computer keyboard, the Gamma Omega TC36K. I've just used it to type up this brief summary of my descent down the "Rabbit Hole" into madness the world of custom keyboards to reach this milestone.

• January 2025,
• Started thinking about replacing my Natural Ergonomic Keyboard 4000 which was starting to fail after twenty years of use.
• February,
• Got a hotswap split keyboard with per-key RGB LEDs, a 46-key Corne v4.1 pre-assembled from Ali Express,
• Started learning the Hands Down Promethium layout, programmed into the keyboard using the VIAL GUI.
• March,
• I replaced the keycaps with lower and more rounded KBDiy KOA profile keycaps,
• Got some UGREEN Magsafe phone stands to try tenting the keyboard.
• April, 
• Replaced the "grey wood" linear 40g switches with lighter OUTEMU half-height "red" 40g linear switches,
• Installed an under-desk pull-out keyboard tray to improve the ergonomics,
• Remapped my laptop to use the Hands Down Promethium layout.
• May,
• Heard about T. G. Marbach's inovative diode-free keyboard designs using some topological graph theory, starting with the Heawood42 split keyboard using the Heawood Graph,
• Started exploring larger graphs for diode-free computer keyboards,
• Worked out how to use the Tutte-Coxeter Graph for 30 to 45-key computer keyboards.
• June,
• Learnt how to use Ergogen and KiCad,
• Designed my own 36-key keyboard PCB using the Tutte-Coxeter Graph,
• Ordered the PCB and 3D printed case from JLCPLC,
• Started learning how to write QMK firmware.
• July,
• Tried various keyboard switches in-person at Yusha Kobo, bought a set of Choc v1 red pros (35g) and a few pink (20g), along with MKB keycaps,
• Joined the Dundee Makerspace, where I improved my soldering skills with some help, and assembled my keyboard,
• Documented how to build the Gamma Omega TC36K keyboard,
• Tested and debugged the QMK firmware.
• August,
• Programmed a 36-key variant of my version of the Hands Down Promethium layout into the keyboard using the VIAL GUI,
• Typed this blog post using the new keyboard!

Anyone is welcome to build their own! The diode-free nature makes this a relatively simple self-build project using commercial PCB fabrication and 3D printing.

The TC36K keyboard PCB was designed using Open Source tools, Ergogen v4.1.0 (using various community footprint designs) and KiCad v9.0.2. The PCB design and pre-existing Gamma Omega keyboard case are under the CERN-OHL-W-2.0 license. The TC36K firmware uses QMK, and therefore is under the GNU General Public License v2.0.