Evergreen watches: the Zenith El Primero cronograph

Founded in Le Locle in 1865 by a visionary watchmaker, Georges Favre-Jacot, the Manufacture Zenith earned swift recognition for the precision of its chronometers with which it has won 2,333 chronometry prizes in a century and a half of existence: an record in terms of pocket watches, onboard timers and wristwatches.

But the true icon of the Zenith Manufacture has gone beyond the chronometry. It was in 1962 that the basics of the El Primero cronograph movement first took shape on the drawing board. The idea was simple: to create an iconic watch that would be launched in time for the centenary of the Manufacture in 1965. The idea was simple, but the technical specifications were not. It was to be the first automatic chronograph ever. Better still, the caliber was to be fully integrated and designed as an inseparable whole. There would be no additional module, but instead a construction built around a column wheel and a central rotor mounted on ball bearings. It would also need to beat at a high frequency in order to be the world’s most accurate chronograph. To complicate matters still further, the movement was to be miniaturised and equipped with a date mechanism. All these factors amounted to an equation so complex that it would take seven years to solve it – four years past the anniversary date.

In 1969 the Manufacture presented El Primero, the first ever integrated automatic chronograph, also equipped with a date and a tachometric scale. It was already an impressive feat in itself, backed by exceptional precision since the calibre beat at the exceptional speed of 36,000 vibrations an hour, corresponding to 1/10th of a second precision. El Primero cronograph made its public familiar with its sub-dial layout of, from left to right, sweep seconds – hours – minutes.

L'icona, El Primero 36.000 VPH (alternanze/ora), con i tre contatori a contrasto
L’icona, El Primero 36.000 VPH (alternanze/ora), con i tre contatori a contrasto

Such an exceptional caliber deserved to be exceptionally tested. In 1970, El Primero took the Air France AF015 flight from Paris to New York – but not comfortably installed on a traveller’s wrist. Instead, the El Primero crossed the Atlantic fixed to the landing gear of the Boeing 707. The temperature stood at 4°C on the tarmac in Paris, whereas 20 minutes later, at an altitude of 10,000 meters, it had dropped to -62° and atmospheric pressure was four times lower. After the landing in New York, during which it was subjected to terrible jolting, the watch showed it had remained accurate to the nearest second apart from the inevitable time-zone difference. El Primero had kept running at 36,000 vibraitons per  hour and required no adjustment.

The El Primero caliber appeared to be suitable to the addiction of complication, due to its power and mechanical resistance. In the same 1969, the El Primero 3019 PHF, later referenced as 410, was introduced. Built around a column wheel and endowed with a 50-hour power reserve, it combines the performances of the world’s most accurate automatic chronograph with triple calendar and moonphase indications. Calibre 410 made its way through the decades until the year 2000 thanks to remarkable reliability coupled with extraordinary precision. But icons never die, and Zenith is now reviving it in 2013 in a 500-piece limited series featuring a slate grey dial.

Il calibro El Primero 4061, montato sul Chronomaster 1961
Il calibro El Primero 4061, montato sul Chronomaster 1961

Probably the most famous complication added to the El Primero movement is the Striking 10th, a movement that allows the measurement of 1/10th of a second. The idea behind this watch is to have a center seconds hand that rotates around the dial not once every 60 seconds, but once every ten seconds, allowing the reader to measure 1/10th of a second accuracy with ease.  Essentially, the sweeping hand here moves at 6x the pace of a normal chornograph’s hand. The three dials of the watch are needed to indicate chronograph seconds (3 o’clock), chronograph minutes (6 o’clock), and the continuously running seconds (9 o’clock). On this watch’s dial, there exists no hours register, and that is because the Striking Tenth does not account of hours at all with its chronograph function.  This El Primero isn’t about tracking hours, it’s about tracking a fraction of a second, though 11 new components.

The symbol of this complication is the El Primero Stratos Flyback Striking 10th chronograph. This watch was on the wrist of Felix Baumgartner, the first man in history to break the speed of sound in a freefall. And with him was Zenith, whose El Primero Stratos Flyback Striking 10th was to become the first watch to break the speed of sound at the very doors of space.Once again, El Primero confirmed its performances: after the jump, lasted nine minutes and three seconds, the watch was still working perfectly upon arrival after being subjected to massive differences in pressure, temperature, altitude and acceleration.

Constantly on the move, El Primero welcomes new complications, while remaining the most precise, the most reliable, the best-preforming – and quite simply “The First”. The movement inspired a whole collection of cronographs, some of them with an open dial in order to show the fast beat of the balance wheel. The last born in the family is quite irreverent, with the “Tong and lip design” from Rolling Stones at 6 o’clock.


Alcune casse della collezione El Primero. da sinistra El Primero original 1969; El Primero striking 10th; El Primero Chronomaster Grande Date.


El Primero Synopsis, con apertura sul quadrante per mostrare lo scappamento in silicio


El Primero 410, con fasi lunari


El Primero Lightweight, presentato a Baselworld 2014. Cassa in fibra di carbonio e quadrante traforato.


Tags: Did you know... Watch history Zenith