Expert: Martin Meyer - 6/18/2007

Question
QUESTION: Can anybody tell me where I can get a pendulum for a Westminster Welby 8-Day Chime Chain wind Grandmother clock from 1974

ANSWER: Hi Jim,
  Pendulums are available or can be made up for most modern clocks. Determining the correct pendulum is based on the clock's movement make and model number, not on the clock manufacturer's numbers. You need to look at the back plate of the movement and write down all numbers found there. Usually, your clock will be made by one of four manufacturers: Hermle, Urgos, Kieninger or Jauch. The maker's name will probably be on the back plate of the movement. There will also probably be a movement number, and sometimes a pendulum length. You also need to know if your clock originally had a wood stick pendulum or a lyre (metal rods) pendulum. With this information you can usually get a correct pendulum from a clock materials house. If the materials house can't identify the pendulum from the numbers you give them, get back to me with the information from the back plate and I'll try to fill in the blanks.
  Thanks for your question,  Martin

---------- FOLLOW-UP ----------

QUESTION: Thank you very much Martin. Here is what the back plate reads.

73
Elgin Clock Division
No(0) Jewels
Made in West Germany
Unadjusted
451-053
85 CM
-----------
70.77

Answer
Hi Jim,
  The only thing that this information doesn't tell me is if your clock originally had a wood stick pendulum or a metal "lyre" pendulum. If you don't know, you can weigh the center weight (right weight is heaviest, left weight is lightest, center weight is what's left). If the center weight is about 4.7 pounds, you need a wood stick pendulum. If it is about 6.6 pounds, you need a lyre pendulum.
  Your movement is a Hermle 451-053 for 85 cm. pendulum. You can get a lyre pendulum for this movement from Merritt's Antiques, part number P-1557. You can get a wood stick pendulum from Timesavers, part number 22766 (5 1/2" bob), or number 22770 (6 1/2" bob). If you get the larger bob and the pendulum hits the sides of the case when it is swinging normally, you need the smaller bob. If your clock is a "pinch waist" style, i.e., larger top and base section and smaller middle section, you will probably need the smaller bob.
  But finally, a warning! Clocks have many variables, and this information is my best educated answer. You may get a pendulum and have to return it for a different size, based on timekeeping, stopping, hitting the sides or swinging too much or too little. Please don't take my answer as gospel, but as a helpful starting point.
  Thanks for your question.   Martin