Chrumm is an ergonomic keyboard prototype, influenced by projects like the Ergodox, Redox, Dactyl, and Pteron. For more information, check out the build log.
Chrumm is provided without warranty of any kind. It is your own responsibility to fulfill all applicable health and safety requirements.
- Fixed-split
- Tented
- Columnar stagger
- Tilted thumb clusters
- Attached palm rests
- Decent dampening
- Reasonably standard layout
- Dedicated function row
The firmware is maintained in a separate repository. The electronics are hand-wired. I mostly followed existing guides, see the QMK Hand-Wiring Guide for a good overview. In particular, I learned about the importance of the diodes from Dave Dribin. I used the following materials, based on availability, affordability, and personal preference:
- 74x MX switch (Cherry MX Silent Red)
- 74x Diode, 1N4148
- Insulated solid wire, 0.5mm (24AWG), tinned copper
- Solder (Stannol Kristall 600, Sn96.5Ag3Cu0.5, REL0, 0.5mm)
- Adafruit ItsyBitsy 32u4 5V 16MHz
- USB cable, A to micro-B
- Zip ties, 2.5mm wide
The body is made out of foam layers, sandwiched between painted
aluminium plates. The layers are manually cut and glued together.
The tools directory includes a Python script to slice the
STL model into layer stencils, which can be printed on paper.
- Laser-cut aluminium plates, 1.5mm
- Acrylic paint primer, suitable for aluminium
- Polyurethane acrylic paint
- EVA foam sheets (Rayher Crepla)
- Artificial leather for the palm rests
- Flexible glue (UHU Max Repair Universal)
For the thumb clusters, I recommend upside-down, 1.25u, bottom-row caps from a cylindrical profile (Cherry, OEM).
The caps can be sourced from a single tenkeyless (TKL) set, though not all of the standard labels will match, and the layer key requires some improvisation.
