Anything mechanical requires oil and Rolex wristwatches are no different. For over 200 years, the correct oil is the Achilles heel for watch accuracy and longevity. “Give me perfect oil and I will give you the perfect watch,” Abraham-Louis Bréguet, legendary French watchmaker is often quoted as saying about the subject. Rolex recognizes the important of a correctly lubricated wristwatch and employ an army of Tribologists to perfect the proper mix of oils used in a Rolex movement.
Emerging in the 1970s and 1980s, Tribologists combine knowledge of the engineer, the chemist, and the watchmaker to understand the multiple stresses on materials used in ultra-precise timepieces. A Rolex movement utilizes at least 10 different lubricants to keep the movement functioning for well over 10 years between services.
Rolex’s latest watch movements are designed and manufactured to extremely fine tolerances found in the medical and aerospace industries. Unlike motor vehicles with large moving parts, a Rolex movement is scaled down to infinitesimally small spinning staffs, pinions, and gear wheels with proportionally large forces involved in friction and wear. According the Rolex, the pressure on ruby bearings or the teeth of a gear wheel in the gear train is equivalent to that exerted by a locomotive on iron tracks. Each tick of the balance wheel corresponds to an escapement impulse and a moment of friction and wear accumulating to some 250 million tick per year. The contact areas between moving surfaces are less than tiny, equaling a few microns.
Tribologists design highly developed, long-lasting oils for insuring that Rolex’s precise movements don’t seize up. Tribologists synthesize lubricants, replacing oils and greases derived from animal hooves prevalent only a decade ago. Rolex is the only watchmaking brand who develop and manufactures its own range of lubricants requiring about a decade of research at its in-house specialized laboratory. Each application inside a Rolex movement requires it own specific oil designed with its own viscosity and temperature range.
Like an automobile engine, the amount of oil is also crucial. Oil for a mechanical watch is not the case of more-is-better. The amount of oil used in the entire Swiss watch industry is said to be about two-liters a year. The amount of lubrication utilized in 50-100 points inside a Rolex movement is measured in microlitres. Tribologists calculate the amount of oil used in each point, and the method for applying it such that each lubrication point has exactly the correct amount. Too much oil can lead to components sticking or slowed down. Conversely, too little oil increases wear and friction affecting timing and reliability.
Tribologists do more than just oil, but also design nanometric coatings called epilames to modify surface tension to insure lubricants stay in place. Additionally, Tribologists weigh in on other areas of friction such as the links in a Rolex bracelet. Tribologists found that by inserting a ceramic sleeve inside each link on the Rolex President bracelet reduces friction and premature wear.
According to Rolex, Tribologists are governed by methodical and rigorous science, yet are matchmakers who marry materials and moving parts together in harmony. Feel free to come into Fourtané and see how Tribology works in action.