To celebrate its 20th anniversary, luxury watch brand Greubel Forsey has launched its very first chronograph, a timepiece that includes the company’s 10th fundamental invention, the Nano Foudroyante EWT (Experimental Watch Technology).
Over the past two decades the focus of Greubel Forsey has been on the refinement and progression of the mechanical wristwatch through fundamental inventions (with associated patents). The Nano Foudroyante is arguably the most technologically progressive to date. It is more than simply the miniaturisation of components to the nanometric scale, it is also controlling energy on a nanojoule scale, thus reducing energy consumption and the number of components.
Detail of the 2017 EWT Nano Foudroyante concept watch (left) with a diagram (right) illustrating how the lightning second hand runs directly from the pallet wheel on the escapement.
After the introduction of a concept watch that incorporated the nano foudroyante back in 2017, the patented technology has been worked on to incorporate it into a chronograph that can measure time below the one second interval, do so accurately and without requiring excessive energy from the mechanism, as that would require increased dimensions for the movement.
The flying tourbillon cage with the nano foudroyante, showing one-sixth of a second intervals.
To demonstrate the feasibility of nano-mechanics, Greubel Forsey has reinvented the foudroyante second hand. The term “foudroyante” means “lightning” and in its traditional form in chronographs, it uses additional energy, as the fraction of a second hand has to run off the chronograph mechanism. However, the EWT version makes use of micromechanical manufacturing methods to produce components so small that the foudroyante can be driven directly by the escapement, continuously, producing virtually no additional drag on the going train.
The nano foudroyante is integrated into the flying tourbillon – the first ever made by Greubel Forsey – and completes one revolution per second, with the foudroyante’s dial remaining permanently aligned vertically. The dial is divided up into six segments according to the movement’s frequency; the oscillation of the 3 Hz balance wheel produces two beats, totalling six beats per second, dividing the second into six distinct segments.
The movement to the Greubel Forsey Nano Foudroyante EWT Chronograph.
The watch is powered by a vertical clutch manual-winding flyback movement. Greubel Forsey’s exceptional finishing comes as standard. Fewer components mean less volume leading to only 428 components and a movement measuring just 31mm in diameter. The resulting white gold and tantalum case is 37.9mm, the smallest so far by the brand with polished relief engravings of “Nano Foudroyante”, “Greubel Forsey”, “2004 – 2024” and “20th Anniversary” to mark the milestone. The watch will be available as a limited edition of 11 pieces. POA.
Learn about other Greubel Forsey watches: the Balancier S, the GMT Sport “Dark Earth”, the Fait Man watch, and the Quantième Perpétuel À Équation.
Author: Andrew Hildreth
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