Double Hinge Boxes

These boxes open both ways. Not particularly useful in and of itself, but entertaining. No, the real advantage is that you can easily remove the lid to use the 2 sides as part trays, or if you just want the lid out of the way. The other unique feature is that the top and bottom are identical (except for the height, if you choose). This is because the hinge also operates as a satisfying snap latch.

I've provided a standard size (interior 87mm x 49mm x 34mm) plus long versions (adds 50mm to the length), deep versions (adds 25mm to the depth), tall versions (adds 19mm to the height of each half) and the various combinations. To create a box, just print any two pieces that have the same X and Y dimensions and then snap them together.

I've also included the STEP files so you can create your own custom sizes with your favorite CAD software.

Printing
One note on printing: the flexing arms that snap the hinge together are printed vertically, which can be prone to cracking at the base. To prevent this, I've set the “small perimeters” speed to 30mm/sec in the 3MF file and set the small perimeters threshold to 5mm. This ensures good layer adhesion and will prevent the arms from snapping off at the base.