Bell Support frame Design

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The bell support system as found was a single threaded tube that connected directly to the steel support bracket that also served as the suspension for the pendulum. There is a set of large, heavy bells. So when the clock struck these bells the vibrations would have substantially interfered with the time keeping of the pendulum. Also the tube did not position the bells to meet where the hammers, as then configured would meet the bell surface.

I decided to have the bell support severed from the pendulum support. The question was, how to do this? One obvious way was to run a tube or rod from the cast iron base to the bells. The problem with this idea was that the bells are rather heavy and the tube would need to be over 22" in length to clear the clock frame, and this was the altered, shortened length. The original bell arms were over 28" in height. The longer arms required a very strong spring for recoil. The answer was to shorten the arm, lower the bells closer to the original frame and thus reduce the required power overall. Eventually a radical redesign of the simple single arm pull, was replaced with a compound system that allowed for a lower power consumption as well as tucking the hammer levers more within the frame of the clock. This gave the movement a cleaner look without the long outstretched hammer arms looking like someone with the their arms on their hips. (see photos below).

It was decided to create a subsidiary frame, complementing in design and attached to the original. Upon this the bell system is supported. The brass stock required was 1/2" thick. It was cut by hand from solid plate and secured with counter-sunk hidden screws. Now the bell vibrations were severed from the pendulum support mount. The bracket also added an extra complexity to the frame and enhanced the overall "presence" of the movement.

Brass 3 train (96a).JPG (596525 bytes)

Shown here is the clock as found. The bells are attached to the black, cast iron brace which holds the pendulum assembly. Notice the very long hammer arms. It may be that the bells were mounted above on a frame or separate case that housed the clock. Thus the bells would have then been connected to an external case rather than the pendulum mount.
Brass tower clock-Saff (1a).jpg (360672 bytes) Shown here in black is the wooden mockup of the the bell mount frame designed to blend in with the original frame. The hammers and first iteration of the hammer lever-pull system are also seen.

Brass tower clock-Saff (3a).jpg (487165 bytes)

The bell frame assembly is now painted brass to see how it blends into the original movement frame.
Brass tower clock-Saff (6).JPG (361039 bytes) The completed mockup with the bells attached, prior to the re-working of the hammer pull system. The bells later will be better positioned in relation to the frame.
Brass tower clock-Saff (29).jpg (592854 bytes) The 1/2" thick brass stock being cut for one of a pair that will become the bell support frame.
Brass tower clock-Saff (30).jpg (639718 bytes) One of the original strike train frames being drilled to accept the counter-sunk and hidden screws which will attach the new bell support frames to the originals.
Brass tower clock-Saff (41).jpg (667843 bytes) Completed frames system in place, but before final finishing. Note also the new pendulum support system in front of the  frame keeping with the overall curvilinear design of the original clock.
Brass tower clock-Saff (42).jpg (625656 bytes) Completed frames system in place, but before final finishing.

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