This 18s Hamilton pocket watch is something I repaired outside of school, as an independent subcontractor for a local watch/clockmaker.

American pocket watches were measured in sizes, not in ligne size. An 18s movement is one of the largest, especially by wristwatch standards. Far from the thumbnail size of ladies wristwatch movements, it's almost as big as my the palm of my hand!

This watch uses a fully-capped escapement, which means that the balance, pallet and escape wheel all have cap and hole jewels. Since this was manufactured around the turn of the century, they're all non-shock-protected screwed chatons, which makes cleaning a multi-stage affair.

Large watches like this are use "full-plate" movements, which place the balance above the rest of the geartrain. It's tricky to assemble, since all of the geartrain pivots (plus pallet) must line up with the pillars before the plates will properly seat. Tip: assemble the plates "upside down" (dial-side up) to make things easier, and mount the balance later.

The fully-capped escapement and the sheer size of the oscillator mean that this movement should be capable of impressive timing results, and indeed it is. This watch achieved a positional delta of less than 15 seconds. I had to burnish a couple of pivots, but that is to be expected on something more than 100 years old, which is regularly worn and run.

Turn-of-the-century pocket watches can be truly nightmarish to work on, but they can also be amazing timekeepers if properly maintained. This one has some damage to its dial from the set lever, but otherwise, the enamel looks as good as the day it was fired. 

It's tough to make a business out of servicing this kind of watch in the "real world" (the repair cost often exceeds the value of the watch), but it's nice to get this experience while I can.