Oils for the lubrication of clockwork are products of the vacuum distillation of petroleum oils, bone oil and solid carbohydrates. The quality of oils and their proper use are essential to the reliable and stable operation of the clock mechanism.
Clockwork oils should be applied to thoroughly washed, dry surfaces of parts completely free from dust, dirt and washing liquids. Applying oil to a poorly prepared surface changes its physical and chemical properties, causing it to spread, thicken and dry, causing friction to increase, and subsequently stopping the watch. For maintenance of work of the clock mechanism in the set limits of technical characteristics of oils should possess following properties: high smashing ability; well to wet well rubbing surfaces, but thus insignificantly to flow out; not to change viscosity at change of temperature from - 10 to + 50°C; to be neutral; not to contain water or any mechanical impurity.
Marks of oils differ both on the structure, and on properties. Therefore, it is necessary to strictly observe the rules of application of sentry oils, as the oil functions in the best way in those mechanisms for which it is intended. Depending on the size and function of parts in the mechanism it is recommended to use the following brands of oils: MZP-12 - for lubrication of balance and pallets in wrist and pocket watches; MZP-6 - for lubrication of gears in wrist, pocket and other watches; PMM-5 - for lubrication of small wrist watches; MN-30, MN-45, MN-60 - for lubrication of clock mechanisms and devices of exact mechanics.
Normal functioning of oil in a clock mechanism is determined not only by the quality and purpose of oil, but also by its exact dosage when lubrication of mechanism parts. The amount of oil to be lubricated depends on the caliber and the movement. A large number of devices are used for precise oil dosage, including vane and semi-automatic (needle-type) oil dosages.
Clockwork oils should be stored in closed vials at 20 ± 5°C and relative humidity not exceeding 30 %, in places protected from direct sunlight, heating systems, precipitation and aggressive media. Oil from the bottle to the oil bottle is transferred using a clean glass rod. It is not recommended to pour oil from the bottle through the neck, as it will wash away dust and impurities stuck to the neck in the oil bottle.