The Strike Mechanism (II)

Herschede clock repair

Having read the first part, you will be able to extract more information from this photo of a Herschede strike mechanism.

If you draw a line along the back of the first rack tooth, the line will pass on the right side of the rack post: the angle of the locking face causes a binding effect because the rack must be moved to the right in order to raise the hook lever.

The angle at which the gathering pallet tail meets the rack pin is not at right angles to a line going from the rack post to the rack pin: the gathering pallet tail appears to repel the rack pin. Therefore, the gathering pallet tail must be raised when the rack is moved to the right, which happens when the hook lever is raised.

It should be obvious by now how much force is required to unlock this strike mechanism in order for striking to take place. Activating the strike mechanism should not require a lot of force. This could stop the pendulum.

Since the gathering pallet tail repels the rack pin, the impact of the tail hitting the pin could cause the hook lever to jump up, resulting in continuous striking.

When repairing a clock like this one, I recommend that you NOT alter its original design. Doing so could get you into all kinds of trouble. However, being aware of what causes the problems this design has would better enable you to make the repairs necessary to make it work correctly despite its design flaws.

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