You may have noticed the absence of clock chimes in recent months. On a hot day in June 2025, the approximately 90-year-old clock motor overheated and ceased functioning.
That motor, powered by electricity, was the second in Firt Parish’s history.
The original mechanical clock built by E. Howard & Co., installed in 1873, required regular hand winding and worked via an “escapement mechanism,” powered by suspended weights (at First Parish, this comprised a box of rocks) and a swinging pendulum, which was designed to lower the weights at the precise rate to keep the clock running on time.
Escapement mechanism, By Chetvorno – Own work, CC0,
An example of a clock tower, By Unknown. Drawing is signed in lower left corner: “Ten Eyck, NY” – Scanned 2010-03-12 from Willis I. Milham (1922) Time and Timekeepers, MacMillan Co., New York, p.299, fig.207, Public Domain,
The second clock motor was installed in 1928, and used a “synchronous motor,” an electric motor that used electromagnets timed to the electric grid’s stable alternating current of 60 Hz to drive the gears that move the clock’s hands at a steady rate. The drawback of this type of motor is that it must be hand-reset in cases of power failure or time changes like Daylight Saving.
FPS clock mechanism, with the 1920s-era electromagnetic motor (the black cylinder on the left), that burned out in summer 2025. The left half of this mechanism powers the clock, and the right half powers the bell chimes.
With the latest upgrade, our clock has entered the digital age. It uses a “stepper motor” – an electric brushless DC motor that rotates in a series of small and discrete angular steps to keep accurate time. The advantage of a stepper motor is that the “step position” (which determines the movement of the clock hands) can be rapidly increased or decreased, enabling the clock to be adjusted quickly. Controlled by a computer, the newest clock will adjust automatically to Daylight Saving Time and will automatically reset quickly in cases of power failure.
FPS clock’s newest motor — a stepper motor.
Stepper motor, By Wapcaplet; Teravolt. The original uploader was Teravolt at English Wikipedia. – Transferred from en.wikipedia to Commons by Fastilysock using CommonsHelper., GFDL,
Many thanks to the Town of Sudbury (which owns the clock), Electric Time Company of Medfield, which did the repair, and the great work of the Buildings and Grounds Committee, especially Terry and Gabe!
-Bill Aldrich