A few weeks back I investigated various latching box mechanisms with minimal success, mostly it felt like they were trying to flex the material in the wrong direction which lead to snapping. I tried to make a sliding lid on this box to test a latching mechanism. The lid is a basic sliding lid but when it is fully closed, protrusions on the lid push the side walls out and latch it into the closed position. The walls flex with with the grain of the material so it is pretty sturdy and should last a long time. It's not the best box in the world because the lid is very tight anyway and it doesn't need to be locked into place but it's a successful test nonetheless. (svg here)
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