The pandemic allowed time to service my clocks and help me understand “sympathetic vibration”

I know many of you did your best to adapt to isolation during what is now known as The Coronavirus Pandemic. It changed the way we think, the way we behave and the way we interact with each other. My condolences to those who suffered during this infamous chapter of our lives particularly those of you who lost loved ones.

I had already established my clock hobby long beforehand so the last few months meant that I was able to focus on tasks that I had planned to do but wondered whether I would ever have the time. Corvid19 changed that.

What was also very different was that I could no longer acquire new clocks to add to my collection. So, instead of searching for new ones, I serviced ones in my collection which is not a bad thing.

However, on day 6 of the weekly cycle, the clock would stop and always on day 6. Why?

I was very productive.

I have a small but growing collection of Arthur Pequegnat clocks and was able to service a good number of them and in the process learn the differences, some major and some minor, between early Pequegnat movements and later ones. I honed my skills as a clockmaker, meeting new challenges with each movement I worked on. Four of those clocks are:

Restored Athur Pequegnat Bedford mantel clock
Arthur Pequegnat Bedford shelf clock

Restored Arthur Pequegnat Bedford shelf clock; case and movement are now done.

Arthur Pequegnat Canuk, kitchen clock
Arthur Pequegnat Simcoe
Arthur Pequegnat Simcoe

As with the Bedford, Maple Leaf “pointed top” and the Simcoe the cases, including the dial and movement were done.

Maple Leaf kitchen clock, the “pointed top”

However, I was also able to focus on what I consider my most exciting clock acquisition in the last 3 years, my circa 1850 Scottish tall case clock.

I reconditioned and repaired the case and serviced what I would call the most frustrating movement I have encountered to date, an English bell strike. Plenty of patience is required for this one. It is all about small adjustments and in this case, mostly the strike side. Just when you think things are going well, another issue surfaces. I should have expected that working on a 170-year-old clock is not easy.

McLachlan tall case clock
English bell strike

I was unable to return the movement to the case immediately because it had to go through the testing process which meant constructing a clock stand. I have two other stands but they are too short and made specifically for wall and mantel clocks. Taking ideas from similar test stands online I constructed a 48″ high tall case test stand for my English bell strike movement.

A tall case test stand

The phenomenon of sympathetic vibration

However, during movement testing which lasted for weeks, I encountered a consistent problem. On day 6 of the weekly cycle, the clock would stop and always at about the same point in time. Why? It is something called “sympathetic vibration”. When the clock stops as the weights descended to the level of the pendulum a harmonic phenomenon occurs “wherein a formerly passive string or vibratory body responds to external vibrations to which it has a harmonic likeness”.

In practical terms, when the weights on a tall clock descend to the point where it’s at about the same height as the pendulum, the weights may begin to swing slightly. Since the power that drives the pendulum is now swinging the weight as well, the pendulum does not get its share of power and stops. Sometimes, despite the swinging of the weights the movement soldiers on but in the case of this movement there is insufficient over-swing of the pendulum to compensate for the loss of power.

It can generally be addressed in a tall case clock by fastening the upper part of the case to the wall, or by mounting the case on a solid foundation. For a free-standing clock stand placing a block of stiff foam rubber between the stand and the wall usually cures the problem.

Although the Scottish tall case project consumed a lot of time, it was very satisfying and it was a great learning experience.

More clocks

There are some other clocks I could have mentioned, two German time and strike clocks, a Mauthe and a Muller, a Gufa Westminster chime but suffice to say I made a lot of progress with my collection.

However, beyond the hours of time, it is self-satisfaction and a sense of accomplishment while engaged in productive activities that are the real intrinsic benefits. And folks, that’s what a hobby is all about.


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