Seth Thomas Electric Mantel Clock with Hour and Half-Hour Strike made in 1946.

I repaired this Seth Thomas electric striking mantel clock in a modern-style mahogany case. The movement had a lot of wear, and a pivot of one gear was completely worn off!

This clock uses the Sangamo synchronous motor. The date code on the movement is 46-12 (December 1946).

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Repair job 6580. I replaced gear T5, as one pivot was completely worn away, and its other pivot was 50% worn. I polished the other  pivots and installed 17 bushings.

The motor turns the hands and winds a mainspring that runs the striking. The mainspring has a brace end so it will slip and not overwind. I reduced the brace tension so it wouldn’t wind as far, to reduce future wear. As received, the mainspring wound up 9.5 turns before slipping. I reduced the tension so it would wind 6 to 7 turns.

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  1. I am looking to a repair shop near Shrewsbury Mass and need a Seth Tomas 1946 mantle clock to be fixed

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