Pendulum Wall Clock Runs Slow

To slow the grandfather clock down move the pendulum disk down by turning the adjustment nut to the left.

Pendulum wall clock runs slow.

Adjusting the pendulum shorter will cause your clock to run faster while lengthening it causes it to run slower or simply put speedup slowdown in the pendulum regulation diagram below look for the rating nut at the base of the pendulum which is what raised or lowers the pendulum disk or bob. This is probably just because your pendulum is moving too fast or too slow. Denser air causes the pendulum to move more slowly. Check your adjusted clock against a reliable timepiece several times over the course of a day and continue making adjustments until your clock reads correctly.

Speed up turn nut left to right slow down turn right to left the longeryou make the pendulum the slowerthe grandfather clock. This is adjusted by turning the nut at the bottom of the pendulum. The bob will settle lower making the effective length of the pendulum longer. The clock will run slower.

Push the bob up to make the clock run faster and push the bob down to make it slower. The pendulum disk is moved up or down by turning the adjustment nut. Turning the screw to the left will lower the pendulum slightly and slow down the clock. It runs too fast.

Increasing the ambient temperature of a clock will slow it down from the expansion and lengthening of the pendulum unless the pendulum is a compensating type. Each turn of the screw slows the clock by two minutes per 24 hour period. The shorteryou make the pendulum the fasterthe grandfather clock. To speed up the clock tighten the nut turn it toward your right.

Changing the speed of time keeping is accomplished by moving the pendulum disk up or down. Adjust the bob at the bottom of the pendulum if the clock is running too fast or slow. The length of the pendulum determines how fast it swings so you need to either lengthen or shorten it. To slow down the clock loosen the adjustment nut turn it toward your left.

Lengthen the pendulum by moving the bob down. If the clock is running slow turn the pendulum nut clockwise to increase the rate. Moving a clock to a higher elevation will slow it down as the air is thinner. Pendulum bob with rate adjustment french time and strike.