I was making a box/trunk in the old steamer trunk style. I didn't like the brass corners they had at the hardware store so I printed my own.

These are for 90 degree corners with a 45 degree chamfer on them.

If your trunk does not have rounded over corners, you'll need to attack it with a plane or a router to get the 45 degree corners this requires.

This file does not include screw/nail holes. It is intended that you heat up one of your fasteners and poke the holes where you need them.