Devlog #7
I spent this session finishing the plate and case design.

For the switch plate, I used ai03’s plate generator, converting my actual switch coordinates from KiCad into KLE units to match my diagonal layout. The generator only handles switch cutouts though, so I had to add the encoder shaft and OLED window manually afterward.

For the OLED cutout specifically, I went back and forth on sizing. I initially calculated the exact active pixel area from the display’s diagonal and aspect ratio, landing on 22.4mm by 5.6mm, and later confirmed that matched published specs for this exact 0.91 inch 128x32 panel almost exactly. But once I found and applied an actual KiCad footprint for the specific SSD1306 module in my kit, it gave me a real, confirmed “OLED Panel” reference rectangle at 12 by 29.5mm, which I ended up using instead since it meant I had exact coordinates to work from rather than an estimate, and it also gives a cleaner look showing the whole black display bezel rather than a tightly cropped window.

I also reconsidered how the XIAO should sit in the case after seeing a reference build with the microcontroller mounted visibly on the front instead of hidden on the back. I decided I liked that look better and flipped my XIAO footprint back to the front layer, which meant deleting and rerouting all of its traces from scratch since flipping a footprint doesn’t automatically carry old routing over to the new pad positions.

I also seriously considered adding SK6812 addressable LEDs under the switches, since the kit includes them. Worked out a plan to free up a pin by moving the encoder’s click button into an open matrix slot instead of giving it a dedicated GPIO, but ultimately decided against it. My switches and keycaps are just standard opaque parts, not shine-through ones, so the LEDs likely wouldn’t have been very visible anyway, and it didn’t seem worth the rework for a feature that might not even show up.

Challenges:
The diagonal-stagger switch layout kept creating small complications throughout this whole case-building process, from margin offsets to plate generation to figuring out exact cutout positions. Also learned the hard way that flipping a footprint mirrors the pads but doesn’t move existing traces with it, so that was a full reroute rather than a quick fix. Overall, my time spent with Tinkercad was difficult, and if I had to restart the design I would’ve used OnShape for greater precision and its advanced features.

Next Steps:
The case and plate are both done. Now I’m moving on to firmware, starting with the keymap and getting the encoder and OLED working in QMK.