Designing the modular desk organizer
How the snap-together rail system came to be, why STEP files ship with it, and the three revisions it took to get the snap right.
The desk organizer started as a single pen cup that I kept redesigning every time my desk changed. The fix was obvious in hindsight: stop designing containers, design a rail, and let the containers snap onto it.
The snap fit took three revisions. Version one required a hammer. Version two fell off if you sneezed. Version three uses a 45° lead-in with a 0.2mm interference bump, and it clicks on with one thumb and stays put.
I ship the STEP files with the model because a modular system you can’t extend is just a complicated box. If you design a new module, I’d genuinely love to see it.