Why Service Clocks Regularly?

We frequently see clock owners who tell us that their clock has been running perfectly for twenty years and then go on to suggest tht for this reason there can't really be all that much wrong with it, can there?

The answer to that question can be summed up in one word: FRICTION. Perpetual motion has continued to elude us because of two things we can't overcome, however hard we try:

Gravity and Friction!

Gears

In the case of mechanical clocks, the principle enemy is friction caused by the interaction of two surfaces which rub or slide against each other. In a new or freshly restored clock, nearly all of the various moving parts—steel against brass and steel against steel—have the friction between them dramatically reduced by being burnished, spotlessly cleaned, and then oiled with fresh clean oil of a suitable type and in an appropriate quantity.

Equipment

Unfortunately it is this very oil which eventually becomes the enemy. Over a period of time, the oil degrades, evaporates, and becomes dry and hard. At this point in many parts of the clock (most of all the pivot holes in the plates) the oil picks up contaminants—minute particles of grit and dirt from the environment—and instead of assisting the free movement of the parts, now increases friction on those parts, retarding the movement and acting as an abrasive rather than a lubricant.

The result of this is that after some years of running on degraded oil a clock develops grooves worn into its pivots (the end of the shafts which run between the two plates), grooves worn into its pinions (the small cogs driven by the wheels) and grooves worn into the steel acting surfaces on the escape pallets. The deeper these grooves become, the greater the increase in friction, and eventually the clock will stop. The driving weight or spring—the latter of which is often impeded by coils stuck together with dry oil—is no longer able to overcome the increased frictional forces in the machine.

Pliers

A good restorer carefully dismantles the entire clock, seperating every single part, examines everything for signs of wear, throughly cleans all of the parts, and then examines everything again, noting all of the various parts which have been damaged. The restorer will carefully burnish the pivots, re-bush pivot holes which have become oval instead of round, and often resurface and carefully polish the escape pallets. All surfaces which act against each other are carefully cleaned, and then the clock gets reassembled and carefully oiled with high quality (and often state of the art) clock oil. Occasionally the wear to both pinions and wheels is so severe that some have to be carefully remade to precise tolerances and in a style commensurate with the age and type of the clock.