A handcrafted hammer and gong mechanism is the secret behind Chelsea Clocks’ distinctive, trademark chime. When the strike hammer rises, then falls, hitting the circular gong on the back of the clock case, but the stoke isn’t clean, the hammer can be easily adjusted to better resonate our classic, clear-ringing tone correctly.

Locate the circular plate — fastened in place by three screws — on the back of the case. Removing this plate provides a clear view of the hammer and the gong. When the hammer is at rest, it should be poised roughly 1/8″ above the circular gong. This distance is the perfect height for the hammer to strike the gong accurately, then bounce clear, producing a clean, ringing tone.

A slight adjustment to the wire the hammer head is mounted on is all that is required to improve the chiming quality. With a bit of patience and attentive care, you should be able to restore the trademark tone to your handcrafted Chelsea clock’s striking hammer.

Move the precision hands forward, then let the hammer strike the gong several times while the circular plate is still detached. Observe the hammer action. Make sure the hammer, on the half-hour strike, is still hovering above the gong after the half-hour cycle is completed.

For the next step, position the minute hand ahead to the hour position. After the clock strikes the hour, the hammer should be at rest above the circular gong. Carefully bend the brass wire the hammer head is mounted on ever so slightly to adjust the timbre of the ringing tone. When satisfied with the chime’s sound quality, remount the three-screw circular inspection plate to the back of the clock case. Listen to the hammer strike the gong several more times to ensure that the hammer isn’t rubbing up against the inside of the inspection plate, producing an undesirable tone. If it is rubbing, adjust the brass wire accordingly until you achieve the desired sound.

Once you’ve completed all of these adjustment and repair steps, you can proudly display your heritage Chelsea Clock inside your house or boat — or wherever you prefer keeping it the most — and enjoy the sound of its lovely, signature chime.