Antique clocks, scientific instruments, musical boxes and other mechanical items get damaged if subjected to direct sunlight, extreme temperatures or damp. A common – and one of the worst – places for a clock is over the fireplace. Dust may lock sliding or moving parts of scientific instruments and mechanical items, so keep these in a box or display cabinet when they are not in use. Movement can affect the working of mechanisms too; longcase clocks and wall-hung instruments need a solid wooden wall bracket or mount, if not screwed into a wall.
Before moving a mechanical object, check there are no detachable parts. Do not rely on handles, instead hold the object with both hands under its base. Secure the pendulum of a spring clock by the clip or screw clamp found on many English bracket and mantel clocks. Otherwise remove the pendulum and use folded paper to wedge the ticking ‘crutch piece’ firm. On a longcase or other weight-driven clock, remove the weights and pendulum, and ‘take down’ the clock by separating case, hood and movement. If a mechanism is set in motion while being moved, let it run down completely.
Take special care when moving mercury barometers. Keep them upright in transit. If the mercury moves suddenly, the weight could shatter the glass tube. On a stick barometer, turn the little key square at the base until the column of mercury reaches the top of the tube. Wheel (banjo) barometers must be ‘corked’ by a specialist before being moved.
Winding Mechanical Pieces
With longcase clocks, if you go away for longer than the next due winding, stop the clock to avoid damage to the escapement when it winds down. It should be impossible to over-wind a mechanism; simply turn the key firmly to the point of resistance. Always use the correct key for the item, and make sure it hasn’t warped, rusted, worn or split. To adjust the minute hand of a clock, gently turn the hands clockwise (never anti-clockwise) with your fingertips. If the hands jam, move the minute hand back a fraction but never back past the hour. If this does not free them, leave the job to a clockmaker.
A photographer’s soft-bristled brush with built-in puffer is ideal for dusting lenses and delicate or intricate surfaces. Wipe less fragile surfaces with a soft, dry, lint-free cloth. Avoid metal polishes which can seep into the movement or destroy a valuable patina such as that of a brass carriage clock. For stubborn marks on a glass face, use cotton wool dampened in a mild detergent solution or methylated spirit. Rinse with damp cotton wool and buff gently dry with a chamois leather. Leave major cleaning of parts – especially dismantling – to a specialist. Even oiling the mechanism of a valuable object can be risky if you don’t know where to apply it, and too much or too thick an oil attracts abrasive grime and clogs the mechanism.
If a mechanism stops, forcing it to go may aggravate the damage; leave repair work to a specialist. Get clocks and watches with delicate mechanisms checked and serviced every five years. Those with larger, stronger mechanisms every decade.
With thanks to Readers Digest.
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