When the toc is off your clock, it can tick you off. Regulator clocks can become too fast or slow over time and leave you running late or arriving early. If the swing has gone out of your pendulum clock, it's just a matter of minutes to get the failing timepiece back up to speed.

Vintage grandfather clock clockface
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How to Set a Regulator Clock

Clock Antiquity

When the industrial age began to get underway, timekeeping became a more important effort by more people. The regulator clock – or pendulum clock – was invented in response to this new need by the masses. They started in England and swept to Vienna, where the mechanics of the regulator clocks where fine-tuned and built upon. The Viennese clocks became known for their stellar timekeeping.

Why Rates Change

A regulator clock can seem a perplexing piece of delicate machinery when you open the back to get at the working pendulum parts. It could be the hands have adjusted themselves as they whirl around the face and are putting a glitch in the swing of your pendulum as it goes about its business. It could also be that the clock has been sitting or hanging in an unleveled position for quite some time and has finally lost its well-timed toc. The clock may emit a slight buzzing sound as it struggles during certain times of the day, which can alert you to what is happening behind the face. Dust buildup can also cause damage to the finely tuned pieces inside a pendulum clock. A good blast with a can of air spray can solve that quickly. Allow the clock to dry out for an hour to rid the inner casings of any condensation that may have occurred from the canned air.

How to Regulate

Open the back of the clock and take a good look at the adjustment mechanism on the movement. The mechanism is a notched wheel that is situated just above the hands that you can usually turn with your thumb. The adjustment range should be close to centered. Rotate the rating square to center it if needed. Use the nut at the bottom of the pendulum to rate the clock. Loosen the adjustment nut to slow the clock down or tighten the nut to speed it up. If the hands are sticking or meeting up at any time during the day, gently level them out over the face of the clock with a small set of needle nose pliers. The glass cover could also be the problem if it has warped in its housing due to humidity or age. You may need to adjust the housing with a bit of sandpaper so that the glass sits properly and doesn't hold the hands back from their daily route around the clock.