Pocket watches are great fun to work on. Its the mechanics that constantly amaze me on older watches. They will stop if you dont get them serviced every few years because they are very very sensitive to the accumulation of dirt. How does the dirt get in there? you might ask. The only way it gets in there is from particulates in the air that you cant see. The watch could condense these out of the surrounding air if it is cold and brought into a hot environment. The other big one of course is smoking. If you smoke your gunging up your clocks much much faster than normal – I know becuase most of the cleaning I do for restoration is infact nicotine and dead skin – mmmm lovely (I still love the job).
Anyway this is a pocket watch a did recently. You can SEE all the components and how they communicate forces between each other. If I get a TAG Hauer or a Burberry in (two recent jobs) its just a matter of replacing the whole movement becuase they are mass produced and the same movment will be used by completely differen manufactures. Frankly its boring work to do as a clock repairer and I far prefer pocket watches.
This picture shows an old British Rail station masters watch innards. From the top down you have the drive wheel and additonal cog that keeps the movment going as you are winding it up (clever). The brass cogs then gear down the power and deliver it to the escapement wheel you can see at the bottom under the last brass cog. This escapament cog is always under tension from the spring and is alowed to advance one tooth at a time by the back and forth movement of the flywheel. This regulation between the flywheel and the escapement wheel is managed buy the pallet fork which you can just see sticking out from under the escapement wheel. This is a see-saw affair eith the wheel at one end and the pallet fork at the other end. You can see the other end of the fork in the picutre as they are red jewelled rather conveniently. The picture doesnt show the flywheel which I have removed to show the whole drive chain of cogs.
So if youve wondered what all the gubbins inside the pocket watch actually does, now you know. Its not a complicated machine but that means it has to be very finely engineered as well, hence its sensitivity to dirt build up from the air.
Hope this enlightens you.