Chelsea clocks use a hammer and gong to produce our trademark sound. The strike hammer rises and falls onto a circular gong in the back of the case. If the sound is not a clean stroke, with a clear ringing tone, it can be adjusted as follows.
On the back of the case you will see a circular plate, held in place by three screws. Removing this plate allows a clear view of the hammer and the gong. At rest, the hammer head should be poised about 1/8″ above the circular gong. This allows the hammer to strike the gong and bounce clear, producing a ringing sound. A slight adjustment of the wire that the hammer head is mounted on is all that is necessary to improve the sound quality. With a little patience and care, you should be able to restore the trademark Chelsea Clock sound to your clock’s strike.
Move the hands ahead and allow the clock to strike several times while the plate is off, observing the action of the hammer. Please note, on the half hour strike, the hammer should remain in the air at the completion of the cycle. Next move the minute hand ahead to the hour position. After the clock strikes the hour, the hammer will be at rest above the circular gong. Making a slight bend in the brass wire that the hammer head is mounted on will adjust the sound quality. When you are satisfied with the sound, replace the inspection plate with the three screws. Check the strike sound one or two more times, making sure that the hammer doesn’t rub on the inside of the inspection plate.
Enjoy the sound of your Chelsea clock.