Have you adjusted the pendulum bob?
The round brass or lead weight on the bottom of your pendulum rod is called the pendulum bob. The nut located on the bottom of the bob is used to adjust the time keeping ability of your clock. If the bob is raised up, your clock will run faster, if let down, your clock will run slower. You can remember this principle, with the phrase GO UP TO SPEED UP; GO DOWN TO SLOW DOWN! Expect an accuracy of at least 1 minute, fast or slow per week. Start by setting your clocks time to an accurate electric or quartz clock or watch. Check the time 24 hours later. If the clock runs fast, turn the nut to the left, and the bob will be lowered, slowing the clock. If the clock runs slow, turn the nut to the right, which will push the bob up, speeding up the clock. Then reset your clock to the correct time again. If your clock has a balance wheel, you regulate the time by rotating a three prong disc which is attached on top of the balance wheel, either to the right or left. Moving one notch equals 10 seconds per day. Keep a written record of the distance you turn the nut (or move the disc) each day and the resulting minutes off. Do this every day until you have zeroed in within 1 minute of the correct time. Then, switch to checking your clock every 7 days, using the same process until your clock keeps time within l minute per week. It may be a time consuming chore, but you only have do this once.
Remember, mechanical clocks are not as accurate as modern day electric or quartz clocks! When you regulate the pendulum of your clock, you are attempting to achieve the best timekeeping possible from a mechanical clock between weekly windings. Old clocks are just that, old clocks. You canít expect the same accuracy from them as you would and electronic clock. Give them a break and enjoy them for what they are.