Patek Philippe Multi-Scale Chronograph 5975 (5975P-001)

In 2013, Patek Philippe moved its U.S. headquarters to a larger space in Rockefeller Center, where the brand has had its North American base since the late 1930s. With more than 34,000 square feet, of which 8,000 is devoted to watchmaking workshops, Patek more than doubled its capacity for after-sales service and repair in the U.S.

The expansion has allowed the brand to accommodate 20 watchmakers, with the potential to grow to as many as 40 in the coming years, in a space that is closely modeled on the Geneva headquarters, right down to the benches. Entering the New York workshops is like stepping into a Swiss bubble in the middle of Midtown Manhattan. This same design model is applied at Patek Philippe facilities worldwide so all are consistent with brand ideals.

With the exception of particularly old or highly complicated pieces, such as tourbillons and minute repeaters which are sent back to Geneva and often handed to the watchmaker who originally worked on them, any watch dating back as far as 1960 can be repaired in New York.

Each year, approximately 10,000 watches at various levels of complexity are serviced and repaired in Rockefeller Center. "If a watch is a level four, we may only have two people who can work on that watch, which is why the wait time can be long," says Larry Pettinelli, president of Patek Philippe U.S.A. "We have 1,400 watches in the queue at any given time."

Each of those watches must undergo strict quality control measures before returning to its owner. "When the watch comes into Q.C., we have to make sure that whatever the customer wanted done has been done," explains watchmaker Jason Bird, who also details the additional tests that are administered before a Patek is released back to its owner.

The first of these is a water resistance test using a waterless testing machine that seals the watch in a chamber and applies air pressure. When the test begins, a micrometer sensor is lowered to touch the crystal of the watch and measures the case. When air pressure is applied, the sensor measures the compression of the case from the atmospheric pressure. "When you increase air pressure and the case is compressed, if it stays squeezed, we know the air is not leaking into the case," explains Bird. "If the micrometer measures that the case is not staying compressed, we know that air is getting into the watch, and, subsequently, water would get into the watch." All the watches are tested at .5 bar and at either 3 bar or 6 bar depending on the model—sport watches, such as the Aquanaut, must pass the higher level.

The watches also must meet scrutiny for aesthetics under high-powered microscopes to check for lint, scratches, and other tiny flaws. And to illustrate how miniscule a failing detail can be, our group of seasoned watch journalists was invited to find the problems with rejected watches, and not one could. Examiners also check the condition and function of the buckle and crown to ensure they operate smoothly. Each watch must meet standards for how the hands set, when the date changes, and even the exact time a moon phase advances to meet Patek Philippe's strict standards.

Once the aesthetic tests are completed, the watch is checked on timing machines for precision in six different positions, and then the tests are repeated 24 hours later to ensure it meets tolerances of -3 to +2 seconds per day. Power reserves are also tested to ensure they meet the minimum requirements of each movement. Automatics are put on the machine fully discharged, wound for a certain amount of time depending on the caliber, and then set to noon. "The watch has to run for 12 hours, trip the date, and most will have to run another six hours after that," says Bird. "If it passes that test, we know the auto system is working efficiently. If not, we send it back to the watchmaker."