Clocks, Watches/Ridgeway grandfather clock
QUESTION: Hi--I have a Ridgeway grandfather clock with URGOS UW326910 movement in it and i can't slow the clock down !(I bought the clock used) Could you tell me how long the pendulum and the weight of the bob should be for it ? Thank you Carl
ANSWER: Your clock movement is a 94cm pendulum drop. That means from the top of the pendulum suspension to the center of mass is 94cm. To find the center of gravity; lay the pendulum across your hand and find the balance point. (it is usually near the top of the bob but depends on the pendulum design.
A Lyre type pendulum for a 94cm drop is usually about 35" long but, as I said, it will depend on the pendulum design. The more weight there is near the top of the pendulum the higher up the center of gravity will be.
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QUESTION: This clock now has a wooden 27" pendulum with a 4.5" bob on it and it will gain like 2hrs over night ? Thanks Carl
The pendulum obviously needs to be longer. You can find the center of mass by laying the pendulum across your hand at the balance point. You will need 94cm from the top of the pendulum suspension spring to that center of mass so includ the spring and leader with this measurement.
This will allow you to figure out how much longer your pendulum needs to be. It will probably end up being pretty close to 35".
You can buy a new wood stick that is longer, switch over your bob, top piece and rating hardware. If you do this, I would start long with the clock running too slow. Cut the stick a couple inches at a time until you can get it to proper timekeeping.