There will be no more updates to this page. Go to the new GitHub page for the latest updates.

The GitHub page has updated models and better instructions. I do not update things on Thingiverse anymore because this whole website is rotting away due to blatant neglect of its owners, and all its bugs make editing anything here risky and cumbersome.

If you remix this and publish the remix on Printables, you can link to this same model on Printables itself (224713).

Old description follows. You shouldn't be reading this, why aren't you on the GitHub page already?

My godson has some kind of obsession with collecting small things in small chests, and he wanted a chest with a working lock. So, for his next birthday I took athey's Small Hinged Treasure Chest and designed a lock mechanism for it. Of course it is the most basic lock possible with only one possible key and picking it is trivial, but it is functional.
I also spiffed up the overall looks of the chest with extra details like the excellent wood texture from the OpenForge Wooden Floors by devonjones.
The hinge has been made slightly beefier to reduce the risk of it breaking.

To unlock the chest, rotate the key counter-clockwise and open the lid while keeping the key turned. The lock cannot be left in the open position, closing the chest automatically locks it. This video demonstrates how the chest works.

I made three different key designs, although the skull key will probably be the most popular with little (and big) children by far :)

Assembly is rather straightforward but the parts must be printed and mounted accurately for the lock to neither fail to close, nor be sloppy. See the images for instructions. On a well-calibrated printer the parts should only require minimal post-processing to make them fit. If your prints tend to be sloppy, some extra sanding and scraping may be required. See the post-printing section for more details.

The dimensions are 76 × 46 × 57 mm for the bulk of the chest, and 76 × 51 × 58 mm with the hinges and details included. It should be possible to scale up the model slightly, but you may need to scale up the latches a tiny bit more in two of the three dimensions to keep them a tight fit.

If you want to print the chest at 200% size, print the models with Size200 prefix. These are already upscaled to 200% (meaning about 152 × 102 × 116 mm), and have been modified with reduced wall thickness and appropriate tolerances for the size. I haven't printed this larger model so I cannot guarantee it will work perfectly. Feedback is welcome!