I had the urge to make a wooden mechanism, and decided to make a working 4-tumbler cylinder lock. The keys were the one of the first things I tried since I wasn't sure how practical they would be to make, however they worked out fine after a few practice tries. I gave the practice keys to the daughter of friends, who was a toddler at the time and fascinated with keys. I also fashioned an "M" for her initial as a key fob. So when I made the final keys for the lock, I made a matching "R" in the same "font" for my set of keys. By design, only the Bird's Eye Maple key works properly in the lock.
The lock itself took a few tries to get right. Oddly enough, the toughest process was drilling straight holes in the cylinder for the pins. I ruined a few cylinders before I managed to get that right. Ultimately, I decided there were enough pieces and enough processes to be done to the pieces that I needed to write a procedure to do things in the correct order. It ended up being around 70 steps. I also drew the lock using a CAD program to ensure that all the pieces would line up and things that rotated would have enough room, etc. I then took the precaution of making 2 or even three pieces of critical parts. This was not too hard since when a machine is set up, making an additional part takes little extra time. This allowed me to keep to the procedure when I made a mistake and ruined a part rather than going back to square one.
The lock comes apart by removing a side so that most of the inner workings can be seen (and more internal details are
here). The removable side is held on using a couple of magnets mated to a pair of screw heads. The main section of the lock can also be disassembled by removing locking wedges that fit into slotted pins attached to the ends, since I wasn't sufficiently brave (foolhardy?) to just glue it all together when I thought I was done. There are around 44 pieces in the lock; all are wood except the springs, magnets, screws on the pin cover and the rather ugly-looking screw heads that mate with the magnets. Despite having serious concerns early on about friction preventing the key sliding past the pins, the lock works well. Just like your standard metal lock, unlocking it causes the hasp to spring up, and it then can be rotated. Closing the hasp causes it to lock into position again.
| Material: | Body: | Birch |
| Top & bottom: | Walnut |
| Cylinder: | Boxwood |
| Hasp, pins, locking pins, locking wedges: | African Blackwood |
| Alignment pins: | Toothpicks |
| Keys: | Bird's Eye Maple, Maple Burl, Swiss Pear |
| Keychain fob "R": | Satinwood |
| Finish: | | Clapham's beeswax polish |
| Time: | | Approx. 52 hours |
| Done: | | March 9, 1997 |
