A fellow watchmaker once asked me if I knew what the slits in a riveting stake were for. I finally found a good answer—while crafting my horological arch-nemesis, no less.

Turns out, they're great for supporting the slender steel peninsula, which holds the regulating pins on a pin regulator, when securely affixing the pins in place. After slipping both pins through their respective holes, nest the pins into an appropriately-sized slot and drive them home.

Thankfully, most of the timepieces that cross my bench have no need for a pin regulator at all, let alone require making a replacement, as they are generally free-sprung. So the use case is rare. However, every so often a historically important timepiece comes along that warrants the work.