The care with which watchmaker Ferdinand Berthoud’s legacy is cherished is evident in the great lengths that Chronomètre Ferdinand Berthoud goes to, in authentically interpreting the ideals and techniques of the 18th century master in its collections. The watches are not random creations but inspired by particular clocks and timepieces created by Berthoud. In the case of the new FB 3SPC, inspiration comes from the No.26 decimal watch signed by Berthoud’s student, nephew and successor, Louis Berthoud.

The subject of study in this instance is the balance spring. As such, the new manual-wind caliber FB-SPC that drives the FB 3SPC sports the main components of the escapement — the balance wheel, pallet fork and escape wheel — on the dial side, with its principal feature as the cylindrical balance spring. More than three years in development, the caliber FB-SPC is the only movement with a cylindrical balance spring to earn a COSC certificate. The workings of the escapement can be viewed from the front, and the rhythmic breathing of the balance spring can also be viewed from a porthole opened into the case middle at 9 o’clock. The rest of the watch face — there is no dial — are central hands for the hours and minutes, small seconds at 6 o’clock, and a power reserve indicator at 2 o’clock, showing 12 hours for each mark on the three-day scale.

Besides the workings of the movement, the very architecture of the watch is also very openly displayed: the mainplate forms the core of the movement sandwiched by six bridges on the dial side, and ten at the back that hold all the movement components together. Reflecting the aesthetics of the time of Louis Berthoud, which was transiting from an ornate and elaborate baroque style to the more tempered elegance of neo-classicism, the decoration of the caliber FB-SPC is accordingly restrained, and refined, eschewing the flurry of conventional finishes for the relative austerity of matte surfaces executed by fine sandblasting, outlined by polished bevels. The balance bridge, in a distinctive heel shape, references Ferdinand Berthoud’s No. 3 astronomical watch; the barrel bridge that spans 120° at 12 o’clock recalls a bridge on the No. 2575 quarter-repeater watch made by Louis Berthoud.

According to Chronomètre Ferdinand Berthoud, more than 100 hours are required to decorate the 230 components of the movement. On top of this, is the know-how to fabricate, install and adjust a cylindrical hairspring. In its paean to 18th century watchmaking, Chronomètre Ferdinand Berthoud had to develop this know-how on its own, in the absence of specialised literature on the matter from the period. Two hand-crafted curves are needed for the cylindrical hairspring: one at the point of attachment to the balance-wheel, and the other before the pin, which is integral with the balance cock. The vertical aspect of the balance spring exposes it to additional sets of impulses when in the horizontal position. For this reason, most modern-day cylindrical balance springs are fitted inside tourbillons, to even out the influences of these forces by their rotation. The absence of a tourbillon in the cal. FB-SPC means the watchmakers at Chronométrie Ferdinand Berthoud have their work cut out for them, in adjustment and regulation. The two curves of the FB-SPC’s balance spring are entirely raised by hand and their shape checked with the help of a microscope at 20x magnification, to the standard of a certified chronometer.

Two versions of the Chronomètre FB 3SPC are offered: the FB 3SPC.1 in 18K white gold case, 2N pale yellow gold movement components and an eggshell-coloured dial in sandblasted silver-toned brass; and the FB 3SPC.2 in 18K rose gold case with black-varnished minutes track and black-rhodium treated movement components. Both versions are fitted with skeletonised and open-tipped 18K gold hands inspired by a 1785 Ferdinand Berthoud astronomical regulator belonging to the Chronométrie Ferdinand Berthoud heritage collection in Fleurier. Production of the Chronomètre FB 3SPC is limited by production capacity to a maximum 25 pieces per year.

Tech Specs

Reference: FB 3SPC.1/2
Movement: Manual-wind caliber FB-SPC, cylindrical hairspring, 3Hz, stop seconds, 72-hour power reserve
Functions: Hours, minutes, small seconds, power reserve
Case: 42.3mm x 9.43mm; 18K white gold or 18K rose gold; porthole at middle case; sapphire crystal; exhibition caseback; water-resistant to 30m
Strap: Alligator leather strap with gold pin buckle
Availability: Limited to 25 pieces a year