Sargent & Greenleaf model #2 version 6, 1877, page 1.
photos below show the time lock in 'as received' condition. In addition to general dirt
and grime, many of the screws were rusty. Since they were originally heat-blued, these
would have to be cleaned, re-polished and re-blued. Notice too that one of the balance
hair springs had been deformed. This was straightened under a magnifier with fine
Each part including all wheels, barrels, cocks, bridges and plates of the
movement is individually stamped with matching serial numbers, in this lock #778. Since
two individual movement trains are contained within one movement plate, all paired parts
are stamped with a 1 or 2 to make sure seemingly identical parts are properly placed in
each independent train. At this early point in the company's history each time lock was
made as a complete, hand-made unit. The time lock cases were similarly made with each part
having matching serial numbers, this lock having #778. As one can see from the close
numbering between the case and movement, they were made at the same time.
First the lock is completely disassembled and inspected for damage or necessary
repairs. Total parts count 183 including 14 pivot and end cap jewels. Unlike synthetic
jewels of today, the natural ruby under high magnification shows the inclusions and
imperfections present in the natural substrate.
All parts are cleaned in ultrasonic machines, rinsed and dried in an oven (with
the exception of the escapement pallet assembly). This unit has jewel stones that are held
in place by shellac which could be affected by cleaning chemicals and would melt in the heat.
A simple liquid soap solution should be used here in the ultrasonic machine. Screws were refinished and re-blued using a heat gun to bring them to the desired color
Reassembly. Note the yellow wire holding the escapement pallet assemblies to
the top movement plate in the background. This trick keeps them in place and their impulse
pins aligned to the balance wheel's safety rollers which are mounted on the same plate.
Otherwise these units would fall out when the top plate was tipped over to be lowered onto
the the wheels mounted in the lower plate. They cannot be left in the lower plate with the
other wheels since they tuck under the balance wheel cocks. Their later-made
model #4 had both balance wheel cocks mounted on
the lower plate making reassembly much easier.