Seth Thomas Electric Striking Clock, Made in 1947

Here’s a Seth Thomas electric striking clock in a modern style mahogany case. The dial is “skeletonized” so that the wood shows through most of the brass dial. This clock’s case is 8 7/16 inches tall and 14 1/16 inches wide. The minute hand is 2 1/2 inches long.

The motor has the date code 47-10 (October 1947) and the label inside the back door has the date code 47-11 (November 1947).

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The movement has a Sangamo self-starting synchronous motor. The motor drives a reduction gear train which drives the hands, and winds up the strike mainspring. The strike mainspring has a bridle end which slips in the barrel, so the spring winds only the proper amount. This is necessary because the motor is always winding the mainspring. The end should slip when the mainspring is wound 6 to 7 turns.

This movement is very reliable, and will run for years. When it finally stops, there may be severe wear to the pivots or gear teeth. This one stopped because one of the motor wires came off.

Repair job 6256. I tightened the hand-set tension in the center wheel, polished the pivots, and installed 11 bushings. I replaced the motor, and added a terminal strip to reduce stress on the motor wires.

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  1. I have a seth Thomas electric chiming clock and the self starting motor won’t run, where can I get a replacement motor?

  2. I have a Seth Thomas electric striking clock made in about 1947, similar to the one you rebuilt, with theSangamo self starting motor. I have cleaned the movement, bushed and polished the pivots. The motor on my clock is loud and I want to eliminate noise. I f I need to get a new motor, where and what model would I get. Thank you for any help you can give.

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