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Antique Clocks/Seth Thomas chime problem


I have a circa 1928 Seth Thomas Tambour 18 mantel clock, 8-day, 120 movement. The problem is that it strikes 12 chimes on both the 12 and 1 o'clock hours. From 2 o'clock on, it strikes properly. Any suggestions on how to fix this?

the problem is probably caused by a bent snail cam following lever. This lever sits on top of the snail shape cam located on the hour hand sleeve. It should stick straight out toward the face of the clock. You will have to remove the hands and face to access this. If it is angled, take a pair of needle nose pliers and restore the 90 degree bend the tip makes with the lever.

If it is already straight, there is probably a timing problem between the minute hand staff and the hour hand sleeve. You could possibly bend the follower as described above a little bit further to the left and correct the problem. Another way of doing it is to move the hour hand drive gear clockwise one tooth after disengaging it with the driving pinion. If you have to do this feel free to send me a picture of this gear and pinion and I will better describe how to do this.

This problem is generally caused by the clock being run with a run down chime spring. It can also be caused by turning the clock minute hand too fast when going between 12 and 1 o'clock. When you do this be certain to allow the chime to sound for the entire 12 notes when you are setting the clock. Between 1 and 12 o'clock you can turn it as fast as you want and the clock will synchronize itself.

Sorry for the delay but we have family here for Thanksgiving and had to go Black Friday shopping.  

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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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Four patents.

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