Overwinding
Regarding ‘overwinding’ of clocks as mentioned by D K Stevenson in February’s issue, I am generally in agreement that there is no such thing. However I was called to look at a very large longcase, a corner fitting chiming clock bearing the name ‘Bravingtons of London’. The three-train movement was driven by massive cylindrical weights which the owner raised weekly by hauling on the chains. Having cleaned and serviced the clock six months previously I was puzzled to receive the news that it would not run.
I discovered that the ‘going’ weight was pressed hard against the underside of the seatboard, so much so that it could not be tilted to be unhooked. Even with the pendulum removed the crutch refused to vibrate—clearly no power was reaching the escape wheel.
The problem was resolved by attaching one of the other weights to the ‘going’ weight, thus doubling the power, which persuaded the crutch to vibrate freely for a few hours, thereby allowing the weight to fall clear of the seatboard. The clock then ran perfectly satisfactorily.
Some 18 months later I received another call from the owner: ‘I think I’ve overwound it again’. The situation was exactly as before and was cured in the same way. I can only conclude that the pressure on the chain pulley pivots, caused by the weight being locked hard against the seatboard, had reduced the power available to a level at which the clock would not run.
Could not this problem be regarded, however loosely, as the result of ‘overwinding’?
Jim Walker, UK
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