Finish strike hammer linkages - March 2014




These nine photos show how a set of knurl knobs are created from raw brass
stock. The sixth photo shows thr knurl tool at the bottom of the photo.


The knurls are now installed into the bell support frames. These are used to
adjust the distance from the bell that the hammer sits and thus the loudness
of the strike. Notice in the last photo that the screws which formerly were
of a cheese head design are now cut down to a more subtle oval profile.


Now Buchanan drills the guide holes that will accept the tapered screws to
both secure and position the rod that the bells are attached to the clock
frame. The second photo shows the five different tools needed to make the
specialized threaded and tapered holes. Buchanan had to make specialized
extensions for each bit so as to be able to clear the bell support
outriggers as shown in the first photo. Next is a photo of the tapered
screws. These are the same type used to secure the main frame pillars that
support the remontoire fly fans

Here are two photos of the three birds for the three bell hammers.


These six photos show some of the steps that Buchanan does to make a cross
bar that will serve to connect the bird actuators to the levers that connect
to the bell hammers.

Notice the detail in this part. It could have functioned just as well as a
plain cylinder with a threaded hole. The same for the connecting rod.
Buchanan could have simply used a plain rod with a threaded end instead of
tapering the end before threading, thus giving it an elegant end point. One
can see, a bit out of focus, the carrousels that serve as the cam work to
acting upon the bird actuators.


The bell hammer frames are now disassembled and work begins on the chatons
that will hold the roller bearings for the pivots that will hold the arbors
connected to the bell hammers. The chatons are seen in the first photo. Next
the holes are threaded in the hammer frames. Next all of the frames are
shown with the chatons attached. The last two photos show the assembled
frame before and after the hammer arbor is installed.

Here are the various parts used for the hammer head levers.


The hammer lifting levers are now complete. The first photo shows the center
pivot cylinders, again with beautiful machined detail.

This photo shows a close up of the knurl knobs used to adjust and lock the
hammer head positions as it relates to the surface of the bell as well as
the pivot upon which these are attached. The cross member upon which the
hammer rod pulls are mounted is now finished off.