Antique and Vintage Mechanical Clocks

You have just brought a clock that was running smoothly when you first saw it. You bring it home, select a location to display it, reattach the pendulum, and give it a slight push but after a few seconds, it stops. One crucial aspect of keeping a mechanical clock functioning properly is making sure it is “in beat.”

This article assumes that your clock is equipped with a pendulum rather than a balance wheel or platform escapement. A pendulum on a clock is a weight suspended from a pivot so that it can swing freely back and forth. The pendulum’s regular, consistent motion is used to regulate the time on your clock.

What does In-beat Mean

When a clock is “in beat,” it means that the pendulum swings symmetrically, with equal time intervals between the ticks and tocks. This even rhythm ensures that the escapement releases energy consistently, which is essential for keeping accurate time. You will hear a steady “tick-tock” rhythm, with equal spacing between each tick and tock.

If the rhythm sounds irregular—like “tick-tick… tock-tock” or has uneven gaps—the clock is out of beat, meaning the pendulum is not swinging properly in balance.

As the pendulum swings, it controls the release of the clock’s escapement, which allows the gear train to move in a controlled manner, driving the clock’s hands forward.

How to Correct a Clock That’s Out of Beat

Method 1: Tilting the Clock

One way to fix a clock that’s out of beat is by gently tilting it sideways while listening for the sound to become even. Once you hear an even tick-tock pattern, prop the clock in place to maintain the tilt. While this method works, the clock may end up looking tilted and uneven in its position.

Method 2: Adjusting the Crutch

The second method is more precise and involves adjusting the crutch. The crutch is the rod that extends down from the pallets and rocks back and forth with the escape wheel. The pendulum rod passes through a crutch loop or fork at the end of the crutch, and it’s important to ensure the pendulum rod sits in the middle of the loop without being too tight or too loose. The crutch connects to the pendulum leader, which is then attached to a post with a suspension spring.

For mantel clocks, making this adjustment is relatively straightforward, as they usually feature rear access doors. Through these doors, you can easily reach the crutch, pendulum rod, and bob. If your clock has a wire crutch (brass wire is pliable), gently bending the wire slightly at the midpoint in either direction will help correct the beat.

For English and German-style clocks, you can make a slight adjustment to the crutch on one side or the other since the crutch is connected to the escapement arbour and fits snugly but moves enough to make an adjustment. Moving it alters the entry and drop of the escapement pallet and corrects the beat.

Additionally, you may need to adjust the height of the escapement by loosening two screws on the suspension spring post and repositioning the pallet, a process that requires time and patience and is best performed on a movement test stand.

Wall clocks, on the other hand, require more effort to perform a beat adjustment. To access the crutch on a wall clock, you’ll need to remove the hands— the minute hand is held by a screw or pin, and the hour hand pulls off— and then remove the dial, which is usually attached with screws. Once these parts are removed the crutch can be adjusted.

Minor beat adjustments on wall clocks can also be made by slightly tilting the clock. The tilt may or may not be noticeable.

A One-Time Procedure

The good news is that you’ll only need to adjust the beat once. Whether your clock is a wall clock, mantel clock, time-only, time and strike, or time, strike, and chime, the principles remain the same. This is a straightforward DIY procedure, so professional help is not necessary.

Moving the Clock

If you relocate the clock to a different spot, it’s often necessary to repeat the process of checking and adjusting it to be in-beat. This is because changes in the environment, such as variations in surface level or vibration from nearby activities, can affect the pendulum’s swing. After moving the clock, always recheck if it is in beat. You may need to re-adjust the pendulum’s crutch to ensure a smooth and even tick-tock rhythm.

Final thoughts

If your clock is not running and efforts to put it in beat have no effect, several underlying issues require remediation. If there is significant wear of the pivots or pivot holes, wear in the pinions, there are broken components, or dried oil creating friction in the movement, all of which may need attention to restore the movement’s function.

After the movement has been serviced, adjusting the clock to be in-beat becomes a much easier task.

For a more comprehensive or technical examination, horological journals, articles, and bulletins provide in-depth insights into the physics of escapement design and theory. However, I trust that this simple explanation will suffice.

There’s something wonderfully calming about the rhythmic ticking of a perfectly in-beat clock.