Time Lock Drawer (using ice, locks for ~120 mins)

thingiverse

This is a time lockable drawer that slides into a stable housing. It can hold small things like keys. You can fill a small amount of water into the Housing, close the drawer and freeze it. After you take it out of the freezer, you are not able to pull out the drawer for about 2 hours. This allows a lot of possibilities that require some patience. You need to print some plate support for the inner part. I tested it with PLA, 210°C, no leaks detected after a fiew tests, no cracks. In a 19°C environment it took about 120 minutes until the drawer could be pulled out again. No water is dripping out, you don't need to refill again, just slide it back in and refreeze. Freezing took about 4 hours. Fill the water just below the upper edges of the triangles inside the housing.