This series shows the
making of a clock pinion for a very early Smith's fusee marine lever
bulkhead clock. This clock required extensive restoration
including grinding new pallets, cutting a new escape wheel and extensive
repivoting. It is yet another example of what happens when someone
attempts "hit or miss" adjustments without knowing precisely
what to do. The English covered pallets were "ground"
for some kind of adjustment and the escapement was hopeless.
This clock is one of the earliest Smiths marine levers and the owner
wanted it restored to function. I wish I had before pictures and I
apologize for the lack of photos showing the pallet making. The
pinion was badly rusted and unuseable. I always cut two
good pinions. One from brass and the final one from steel.
This is because pinion cutters wear fast because they are cutting steel
and the setups need to be precise. If the cutter is off
center just a hair the pinion will be useless. So, I make one from
brass, ensure it is correct, lock the machine settings and then load
steel. The
next few shots show making the brass pinion. Now
a steel blank is prepared to the correct diameter and the pinion is cut. Because
this pinion carries the friction wheel that drives the motion works (the
center pinion is actually for the sweep seconds hand), it extends
through the plates and is about 4 inches long. This is yet another
reason the Habegger comes in handy.
Pressing the wheel on the arbor.
The
pinion installed into the clock. It is carrying the wheel in the
lower right hand corner that is driving the intermediate wheel.
Here is a larger view comparing the old and new pinion. You
may be better able to s the rut damage in the old (lower) pinion. The
bearing above the shoulder is a different diameter because I rebushed
the hole due to wear.
|