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The following text was written in an easy manner on purpose, to facilitate the search for our products
in the world wide web.
Watch and clock oils are special lubricants for very fine mechanisms. All of these mechanisms are using
indicators or gauge-discs. The dimensions of a clockwork are tiny. Bearing and shaft diameters can be
less than one millimeter.
Bearings and sliding zones are lubricated by watch and clock oils. The materials used here can vary.
Steel, brass, sapphire, ruby and increasingly often plastics are being used. Some applications even use
die-cast zink, magnesium, aluminum and stainless steels. Some of the metallic materials are additionally
galvanically coated.
In these tribologic systems watch and clock oils have to reduce friction and wear. Surface-pressures in
the bearings are sometimes very high, whereas the sliding speeds are very low. At a speed of 1mm per
day (0.00001157mm/s), the hour hand of a watch or clock is permanently in a state of boundary lubrication,
the barrel-arbor is moving even slower. The axis of the day-disc turns one time per month. Some astronomic
watches contain shafts, that have less than one revolution in 10 years (external planets).
The watch or clock oil must not act corrosively with the materials used. It must not resinify (become gum-like).
And -very important- it is supposed to stay in place and must not creep away. The amounts (volumes) of
lubricant applied are very small: 0.05 to 2 microliters. One microliter is one thousandth of a milliliter.
Instrument oils are mainly composed similar to watch or clock oils, but they have a different profile of requirements.
Instruments like gyrocompasses, electrically driven miniature drives, scanners, etc.) often work with high rotational
speeds. Thus, the instrument oil is supposed to have a low viscosity. It must not vaporize or volatilize. In aeronautical
instruments, temperatures can reach as low as -60°C.
Precision oils for instruments in car dashboards require a range of temperature of -40°C to +150°C. Some of the
systems produced today, are reaching the borders of what is technically possible. The step motor of a swatch for
example is ticking once per second. The same motor turns in a dashboard instrument with 20,000 rpm, just by a
different electronic control. The precision lubricant in the bearings has to be of highest quality with lowest tolerances
in production. A deviation of only a few percent in viscosity can already lead to failure.
Watch and clock greases/ instrument greases.
Out of watch and clock oils and instrument oils, precision greases can be made. A precision grease contains
the basic oil and thickener to provide the greases with structure. These thickeners often are metallic soaps,
anorganic powders, micronized solid lubricants or polymer powders.
Instrument greases very often are soft greases with a content of thickener below 4%. These greases are of a
creamy or semiliquid consistency.
In our watch and clock greases, we often add PTFE. PTFE reduces the static friction and provides emergency
lubricating properties. Contrary to an oil, a grease remains stationary. It also may be used for lubricating open
bearing zones.
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