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Antique Clocks/Zandaam Clock


I bought this clock but received the wrong pendulum.  Can you tell me the correct rod length.  I believe this is an 8 day type.  It has a Hermle 261-080A movement and it is marked 31 cm which I believe is supposed to be the total length from the top of the top post, but it does not seem that total length would fit in the case.  Anyway, it is the rod length that I need.

Yes, this Zandaam movement uses a 31cm pendulum drop. The pendulum length (drop) is defined as the distance between the center shaft center and the bottom of the rating assembly. I interpret this to mean the clearance. This center shaft, of course, is the shaft which carries the hour and minute hands.

Because the pendulum length determines the beat rate of the clock there is no way to use a shorter pendulum, although I did know a friend who installed an antique court house clock in an ordinary room by extending the pendulum upward above the pivot point to increase the moment of inertia. If you are stuck having to use this movement in a case not long enough for the required 31cm clearance, let me know and we will discuss this further.

Another approach might be to extend the pendulum into a routed depression in the clocks base.  

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Tom Williams


I can not think of any questions I cannot answer in regard to repairing antique clocks or radios. However, I am sure there are a few I have not heard and may not be able to answer. If I cannot, I will say so. I have been repairing them since I was a young child.


My experience includes repairing CooKoo clocks, Westminsters, BimBam, almost all antique clocks. I do a bit of repair on battery clocks where the value is sufficient to warrant working on them. I also repair antique (tube type) radios - all makes.

Indiana Historical Radio Society, Illinois Valley Antique Car Club, Military Vehicle Preservation Association

BEE from Cleveland State University

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