Spring-Hinged Glasses Case and Ring Box Shell

Exploring the bi-stable hinges that are common in ring boxes and glasses cases. All 3D printed, some assembly required.

Demo and assemblies at https://youtu.be/JWIdNfnB3O8

The project uses C-shaped springs that clamp onto print-in-place hinges. The springs are print-in-place but require being snapped into the box. The springs give the hinges a bi-stable property that holds a little past the 0 and 90 degrees bend.

The exploration has two hinge snap-in mechanisms: a simple wedge and a buckle design. They're used for two different types of boxes: one resembling a ring box shell and one for a glasses case.

The ring box is not considered a finished product, just an additional proof of concept for the hinges. I didn't do the internal of the ring box (the insert that actually holds the ring) because I tried with TPU, it eventually jammed the nozzle, and I rediscovered why I don't like toying with TPU.

# Printing
All parts are already oriented correctly for printing, with the right sid