Finished the PCB, so this round was all about the case. I went with a sandwich design: a bottom shell that holds the PCB and a top plate with 14mm cutouts the switches snap into, bolted together with M3×16 screws into heatset inserts.I modeled the whole thing myself in Fusion 360 — bottom case, top plate, and the full assembly. Everything’s dimensioned around the real part measurements: 0.2mm tolerance on the mating surfaces, a USB-C cutout on the side wall for the XIAO, and openings for the encoder knob and the OLED. Six standoffs inside keep the board from flexing.Exported all three parts as .STEP (Bottom.STEP, Top.STEP, assembled-model.STEP) — STEP keeps the exact geometry, and the print team converts to STL on their end. Whole thing fits well within the 200×200×100mm limit.Case = done. Next up: firmware.