Polishing is one of the most telling stages in the making of a Rolex watch, providing the metal surfaces with their perfect ﬁnal lustre and smoothness.
Despite the advent of automated technology, the process remains steeped in a highly skilled craft, combining a deft touch with calculated precision, organized steps, and the expressive movements of a performing art.
Concentration is absolute. The eye is focused. His posture is set, the grip on the middle case is firm. Steadiness and strength of hand are essential as the Oyster case is brought against the lathe’s spinning buff wheel. The gestures are curt, sharp and precise, yet subtle, as the case glides and switches through different positions. In seconds, seemingly in a blur, the lightly matt surfaces have gained an even shine, completing one of the final stages of the finishing polish that create a high-quality sheen. The polisher’s craft resembles a precision ballet of the hands and upper body, a carefully choreographed and three-dimensional combination of sensitivity, strength and movement.
And it can be spectacular. In some instances 20 to 30 middle cases are threaded onto a sturdy wooden holder, allowing the polisher to shine their sides all at once. The technique demands greater strength, but the key elements of polishing are mastered to perfection: preparation, handling, applied pressure, speed of execution and lubrication.
It takes several years for a polisher – nowadays known as a termineur, a finisher – to reach such a level of proficiency and assurance. A three-year apprentice ship to learn the trade, its principles, tools, materials, the well-defined techniques and processes in force at Rolex, and to gain the ability to implement them. Followed by approximately five years on the job, to master the multiple facets of polishing and acquire speed, consistency, as well as the well-founded confidence that underpins each individual’s own virtuosity. By then, most polishers have declared sheer love for their craft and insist that such sentiment is essential.
With the benefit of 27 years’ experience, a departmental expert still casts an admiring glance over each polisher at work, from the recent apprentice to the old hand like himself. “Dexterity and a feel for the material can’t be taught at school or in the workplace. These are things that each person masters at their own pace,” he explains, “I’m still learning”.
Too much time – sometimes a matter of seconds – or pressure, and the shape of the case could be ruined as polishing wheels and abrasive pastes remove too much metal. Too soft a touch, and minute scratches, grooves or pitting could mar the surface, potentially unseen to the average eye but easily detected by a skilled polisher’s glance and fingertips. Each component, shape and surface requires a unique approach. And each metal has its own character, demanding a different but no less sensitive touch in each instance.
Gold is softer and easier to shine, but an 18 ct component could be swiftly deformed if it were not worked with precision; platinum is malleable but easily scored or pitted through excess pressure or friction; and the steel used at Rolex, the Oystersteel, is notoriously difficult, demanding more time and strength to achieve an even lustre. An experienced polisher takes one to three months to adapt to a new metal. Today, some even relish the challenge of satin-finishing tough steel over rendering gleaming nobility to precious 18 ct yellow gold.
The watch polisher’s trade has changed immeasurably over a quarter of a century. Polishing used to be based largely on empirical experience amassed by the most experienced hands, who passed down their know-how to successive generations. Over the years the profession has been demystified, gaining a stricter technical base at Rolex.
Polishing methods and criteria are now defined in the production specifications for each watch and component, from the types of machine tools and materials used, right the way down to the techniques and basic handling needed to achieve a specified finish. The materials – abrasive wheels, emery belts, soft discs and polishing pastes – are studied and tested in laboratories before-hand, and adapted to each metal or surface finish.
Technological progress has also brought about the introduction of automation to supplement the human hand, effectively dividing the polishing process into two: surface preparation, mainly carried out by numerically controlled machines, followed by largely manual surface finishing. Both stages, however, involve multiple and progressive layers of polishing until the brightening that provides the required polished or satin-finished final appearance. Here the human touch and eye is irreplaceable.
During automated surface preparation of the freshly machined case and bracelet components, skilled polishers always carry out visual checks of the parts. And the computer-controlled movements of the robot arms in the booths simulate the original human handling of manual polishing. A row of bracelet links is picked up from a rack and automatically switched through a series of precise positions against a polishing wheel for up to seven minutes, removing ridges, scratches and pitting on the raw, machined metal. A few hundredths of a millimetre of surface metal is removed to leave a slightly matt surface, ready for finishing. Hard steel components go through an additional, two-minute automated pre-polishing process, which has the added benefit of avoiding strenuous and repetitive manual labour.
These preparatory machine operations are generally carried out with the help of cutting oil to reduce the heat caused by friction that can alter precious metals in particular. The abrasive wheels and emery belts are coarse, made of granulated materials including ceramic, corundum, silicon carbide, diamond, and sometimes ruby.
Surface finishing, however, is generally carried out by hand on polishing lathes fitted with softer discs. A more recent addition is a polymer pink brush wheel closely related to a kitchen scrubbing pad, used to obtain a satin finish. But many of the materials are natural – woven sisal, compressed merino wool, flannel or layers of cotton of varying density – augmented by polishing pastes with fine abrasives. The rest is down to each polisher’s skill and finesse.
The brilliance of mirror-polished parts demands a smooth and delicate touch at the very final stage of brightening, to ensure that no more than two to five microns of material is removed from the case or bracelet.
A satin finish involves specific techniques at both stages, generally achieved by brushing to produce a surface texture that varies according to the depth and width of the brush marks. At Rolex it is characterized by the perfectly parallel, regularly spaced and homogeneous brush marks – when seen under a microscope. To the naked eye it offers an even, warm, satin sheen. Combined polished and satin finishes on bracelets are down to sheer dexterity and the use of masking tape to protect finished surfaces.
But polishing may also be used to influence shape, not only surface finish, especially on the bracelets. After the initial preparation of the links, bracelets are assembled and polished to achieve a uniform contour along their flanks. It is up to the polishers to eliminate the stepped sides formed by each individual outer link, refining them so that the bracelet elegantly links watch case and clasp with an even curve.
These are the visible sides of polishing. At Rolex, the love of a well-crafted watch is such that even surfaces unseen by the wearer, including inside the case, are polished with the same absolute care and science.