So just for fun, here's a little set of (crappy) photos of the assembly process on a simple Font 69 movement I did Wednesday. The black thing the parts are sitting on in most of the photos is a hockey puck, which works as an excellent assembly surface. For a size reference, this movement is roughly the size of a stack of 3 US pennies.
Here's the movement ~60% disassembled, lots of bits here can be further taken apart, but this is sufficient to run through the cleaning machine for this exercise.
Here's the clutch assembly going in.
Clutch mechanism fully installed.
Flipped over and the wheel train fit.
Wheel train bridge is carefully installed making sure the pivots on the wheel arbors enter the friction jewels and don't get bent. The pivots are in the neighborhood of 8/100ths of a millimeter in diameter, so they do bend quite easily if mishandled.
Winding wheels and sweep second wheel fit.
Top bridge installed same as the previous bridge.
Balance complete is assembled. This is perhaps deceiving, the balance complete here is made of 19 individual components. The hairspring connecting the balance wheel to the bridge is perhaps 2 or 3 hundredths of a millimeter thick, breathing too heavily on it can bend it, so extreme care is used.
This is the shock jewel setting from the balance. The little brass spring is 5/100ths mm thick and must be handled carefully to avoid making it spring from your tweezers flying several feet in some random direction if it's pressed too hand against anything.
The pallet fork and bridge are set in place.
Finally the balance complete it installed. Wind it up and it starts ticking away, if everything's gone well. At this point the necessary components are oiled (some have also been oiled during assembly for ease). The hairspring is checked to be sure it's perfectly level and centered, if not corrective bends are made using tweezers sharper and smaller than a needle point. The movement is timed out on a timing machine, in this case set to run about 25 seconds per day fast to account for all the shocks and movement which will happen when it's worn during the day. Slap on he dial and some hands, case it up and it's ready to go.