Seeking advice for custom module design

I have my UHK connected to multiple computers through a USB switch. The switch has a wired remote, which I have replaced with a breadboard prototype, to validate the wiring (https://imgur.com/VMeDwl9). My next step is to create a custom “module”, with three Cherry MX switches, which connects to the mechanical mounts next to the Y and H keys on the right half. The cable to the USB switch will connect to the bottom of the module, then will be routed to the right, to be joined with the UHK cable inside a mesh sleeve.

Here is a rough PCB design: https://imgur.com/a8el1a4

I have the mechanical mounting hardware and magnets. To mate with the UHK properly, it looks like I should use a bottom PCB for the wiring, and a top plate (or another, inactive, PCB), because the mounting hardware should be screwed into this plate.

I may design a 3d-printed housing at some point, but I’d like to start with a minimal viable design first. Another future goal is LEDs to illuminate the key to show the switch state, but this will require getting power to the module, so I’ll think about that later.

My questions:

  • Are there any existing third-party modules, either for the electronically active mount points, or the “upper” mounts that I am planning to use?
  • Can I get any guidance on some of the exact dimensions needed for a good fit between the module and the keyboard? For example:
    • vertical and horizontal spacing between Cherry switch footprints (5mm? For the plate hole or for the footprint extent?)
    • horizontal spacing between switch footprints and edge of the board/plate (2.5mm?)
    • horizontal offset between the 7 and Y keys (9mm?)
    • horizontal positioning of the screw holes on the male mounting hardware which will be attached to my module (12mm and 17.5mm from the right edge of the plate on the module?)
    • I imagine most of these can be found on a drawing of the PCB and/or steel plate. It looks like right-main.kicad_pcb in the repo might be helpful, but I’m not certain how to read precise dimensions in this file. (The last time I worked with EDA software was about 20 years ago, I’m learning as I go right now).
  • Any thoughts on mounting the magnet properly? As I normally keep my keyboard in a tented position, this doesn’t seem necessary, but I’m curious.
  • Any other advice?

edit: I think I will prototype this on a laser cutter, and maybe experiment with lower-profile switches and a single board to mount both the switches and the mount hardware…

Thanks!

The KiCad PCB files of the modules are available in our GitHub repos, and they’re worth a look.

But rather, the CAD files of the UHK 60 should be needed for your project to create an inverse shape for your module. I’m sorry, but per our policy, we only release the CAD files of products that are no longer available for sale.

My mechanical engineer colleague is too busy to take the requested measurements, and further measurements would likely be needed as you progress with the design. I suggest measuring the requested dimensions with a caliper and iterating the design in CAD software and with a 3D printer.

The magnet or magnet counterpart can be glued in with superglue.