Rolex: Unsung AM Icon Since 2007

Additive manufacturing (AM) has been considered an “emerging” technology for a long time. Fortunately, we have brands like Lamborghini and Rolex to tell us it has emerged. In 2007, Rolex moved to implement AM into its production line. Traditionally, Swiss mechanical watches are made by hand. Rolex is anything but traditional by Swiss watchmaking standards, and their production line is almost entirely automated.

By 2010, Rolex implemented the LiGA process into its production of chronograph (stopwatch function-enabled) movements 4130 and 4161. LiGA is a microelectromechanical systems (MEMS) manufacturing technique that implements additive through a stereolithography (SLA) apparatus — a form of vat photopolymerization — as the LiGA name implies. The LiGA process gets its name from the German acronym for lithography, galvanization or electroplating, and molding.

The masked SLA makes the micromolds, and the galvanization/electroplating makes the part by filling the sheet of molds with a nickel alloy. The mold plate is then lapped, micromachined (because Swiss) and the watch wheels are removed from the mold material and ready to be put into movements.

Rolex uses this process to manufacture the chronograph seconds wheel, a tiny gear with individual teeth made up of cantilevered springs, yielding virtually zero backlash, reduced friction and diminished shock, while also minimizing play between gears. The LiGA process makes this possible because it enables the gears to be formed with tuning fork-like leaf spring teeth featuring flexible mesh surfaces and supported by a rigid central spine. These contacting surfaces of the teeth flex inward to enable shock absorption in the drivetrain, minimizing friction and backlash. This gear could not be manufactured any other way, especially by hand. This is manufacturing on a nearly atomic level.

Rolex uses this AM seconds wheel in two chronographs: the Cosmograph Daytona and the Yacht Master II. The 4130-powered Daytona — in production since 2000 — was upgraded with the AM gear in the late 2000s. Rolex publicly announced their use of LiGA for the Daytona in 2007. Rolex keeps production figures under wraps, but it is estimated that roughly 14,000 Daytonas are produced per year (limited by Rolex to keep resale values high, maintaining an exclusive brand image). So, in terms of the Daytona alone, that is more than 150,000 watches since the implementation of additive, which may not sound like much in terms of “mass production” figures that we are used to in the manufacturing industry, but for a luxury consumer good with a starting price of more than $10,000 (if you can find it anywhere close to retail price firsthand, considering all the dealer premiums and year-plus waitlists), this is mass production.