FERDINAND GEITNER - Round French clock movements have several different means of attachment to the dial plates. Most have plenty of space to clear all the gears and levers on the front plate of the movement. Some also have an extra plate between the movement and dial plate, especially visible escapement movements.
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| Rear view of the dial and additional backing plate showing holes for center wheel, winding arbors and rack post |
Recently a colleague brought in a movement he had very diligently serviced and tested on a stand. It performed flawlessly for several days, keeping good time and striking accurately. He then attached the dial and fitted it into the case.
Suddenly it would only strike one time at any position of the minute hand. Puzzled by this sudden issue, he removed the dial to determine the problem. Suddenly it struck correctly again on moving the minute hand. What could possibly be causing this?
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| View of the rack post and taper pin |
While working on watches and clocks for almost fifty years, I’ve come across many different, initially confusing, situations.
This one was simple but also easy to miss. In the dial plate are the holes for the center wheel and holes for the winding arbors which is normal. But in this instance, on the added plate there was an extra hole close to one winding hole. Its purpose is to clear the post of the striking rack.
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| Close-up of the excessively long taper pin |
If you look closely, you can see the pin securing the washer and the rack to the post. The problem was isolated to the pin which was a little too long in this case. When the dial was secured to the movement, it pushed one end of the pin against the rack thereby locking it. After removing the dial, it sprung back just enough to allow normal rack movement. This effect was so subtle that it was difficult to trace. After clipping both ends of the pin, it fit cleanly within the hole in the dial plate and left the rack completely free to move and count the correct hours.
Watch your pins!
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