A REGULATOR TO STAND THE TEST OF TIME
With its original regulator-type display and its ultra-resistant carburised stainless steel case, the Chronomètre FB 1R.6-1 involves transposing into contemporary language the pursuit of excellence undertaken by the master horologist appointed Clockmaker to the French King and Navy. The appearance of the Chronomètre Ferdinand Berthoud FB 1R.6-1 takes its cues from the Marine Chronometer No. 7. and its FB-T.FC.R tourbillon calibre with fusee-and-chain transmission can be admired through a sapphire crystal case-back and two lateral portholes, offering a unique view inside this outstanding chronometer.
The case of the Chronomètre FERDINAND BERTHOUD FB 1 is built according to a distinctive architecture inspired both by the Marine Clocks of Ferdinand Berthoud and by their gimbal suspension system typical of onboard chronometers.
It is composed of a steel cylinder housing the movement. The molecular structure of this steel has been reinforced by a thermo-chemical process involving the diffusion of vapour-phase carbon, thereby guaranteeing an exceptional surface hardness of 1200 Vickers and making it extremely robust. It is also exceptionally corrosion-resistant and biocompatible.
The case features two octagonal-shaped stainless steel side pieces, giving it a characteristic shape including two lateral portholes at 2 and 11 o’clock – providing a chance to admire the chain-and-fusee mechanism in action. These two openings are complemented by a screw-down stainless steel case-back fitted with glare-proofed sapphire crystal enabling observers to appreciate the high-quality finishing lavished on the FB-T.FC-R movement.
The novel construction of the Chronomètre Ferdinand Berthoud IR.6-1 sets it apart from all existing regulator-type displays and has a mostly solid dial.
The latter is in fact the rear side of the complication plate that provides the regulator-type display. It is made of nickel silver, vertically satin-brushed by hand and black rhodium-plated. Of the three small apertures, the first serves to show the hours, offset at 2 o’clock and appearing on a glare-proofed sapphire crystal disc bearing transferred Arabic numerals striking a pleasing contrast with a white background. The second opening features an original power-reserve display mechanism, distinguished by a large dial cut-out revealing part of the finely sandblasted and black rhodium-plated mainplate. Located in the centre of the finely chamfered, bead-blasted and black rhodium-plated minutes counter, the third aperture displays a hand-engraved “pyramid” motif inspired by an openworked Ferdinand Berthoud astronomical clock belonging to the L.U.CEUM collection.
Meanwhile, the seconds appear around the rim of the dial on a flat inner bezel ring made of black rhodium-plated, bead-blasted and chamfered nickel silver.
The design of the hands on the Chronomètre FERDINAND BERTHOUD FB 1 is a reinterpretation of various hand shapes used by Ferdinand Berthoud in his numerous timepieces.
Their complex and original shapes mean that great expertise is required to make them. The minutes hand is crafted in 18-carat gold, while the seconds hand is made of bronze and the fixed hour-markers and power reserve hand are made of steel.
The dagger-shaped hours and minutes hands are finely cut out and facet-polished. The power-reserve indicator features a curved triangular tip, while the slim direct-drive sweep-seconds hand cambered at its far end is fitted with a round counterweight typical of Berthoud regulators.
The straps of the FERDINAND BERTHOUD FB 1 watches are made in an artisanal manner and hand-sewn from top-quality leather.
These distinctively designed double rolled-edge straps are exceptionally supple yet sturdy thanks to the traditional tanning methods used in preparing the hides.
The finely crafted high-tech FERDINAND BERTHOUD folding is equipped with a safety mechanism built into the cover and serving to open the clasp by means of two push-buttons so as to avoid inadvertent unbuckling of the strap. Optimal comfort on the wrist is achieved by adjusting the length of the clasp by means of push-button built into the lower blade. FERDINAND BERTHOUD chronometers may also be fitted with a resolutely masculine and exclusive 20 mm pin buckle.
A slender, finely structured movement.
The FB-T.FC.R calibre is built according to a unique architectural concept. This hand-wound movement features 18 nickel silver bridges framed by polished titanium pillars surrounding the mechanical organs. This construction is typical of 18th century marine chronometers. The architectural approach is picked up in the design of all the components, and especially in the symmetrical equilibrium of the movement.
The distinctive nature of the FB-T.FC.R calibre lies in its inverted upside-down barrel and fusee, and particularly in the fact that both elements are suspended, meaning held on only one side. A patent has been filed for this construction which saves precious millimetres. At 9.89 mm thick, the movement of the Chronomètre Ferdinand Berthoud FB 1R.6-1 thus remains extremely thin for its category despite the regulator-type display and the new power-reserve indication.
The original fusée and chain mechanism developed by the engineers of Chronométrie FERDINAND BERTHOUD occupies an exceptionally small space within the movement thanks to its “suspended” construction.
The barrel and fusée of Calibre FB-T.FC.R are linked by a chain comprising no less than 474 steel links, including more than 300 pins measuring barely 0.30 mm in diameter and all hand-assembled. The chain measures a total 28 cm long and the maximum tension exercised upon it once in place amounts to three kilos.
When the mainspring is associated with a fusée, the barrel drum turns in one direction when the spring winds down and in the opposite direction when it is wound up, thus causing the chain to wrap around the drum. A distinctive feature of Calibre FB-T.FC.R lies in the fact that its fusée mechanism has been equipped with an unusually designed differential gear.
Calibre FB-T.FC is equipped with a specific system displaying the movement’s power reserve.
A patent has been filed for the extremely sophisticated power-reserve indication mechanism. Visible through a cut-out in the half-bridge on the case-back side, a truncated cone moves up and down along an arbor connected to the barrel. This suspended cone is topped by a feeler spindle in the form of a mobile arm tipped with a watch jewel. The latter’s position on the cone reflects the barrel’s state of wind.
The feeler spindle in turn transmits the quantity of energy accumulated by the mainspring to a set of finely chamfered and rhodium-plated flat levers visible through a cut-out in the regulator plate. Its role is to amplify the displacement of the power-reserve hand. A spiral spring placed at the far end of its travel exercises a force on the base of the power-reserve hand. This spring serves to compensate for the play between the various components of this mechanism and to display the power reserve with peerless precision.
A number of complex mathematical calculations and various tests served to fine-tune the geometry of this spring, made from a nickel-phosphorous alloy in order to guarantee the concentric deployment of the coils in all states of winding and unwinding, and thereby to avoid any unattractive distortion that might also be detrimental to the smooth running of the mechanism. This ingenious device is imbued with the experimental spirit of Ferdinand Berthoud himself, who revelled in exploring solutions resolutely off the beaten track.
Tourbillon with central seconds.
Teamed with the fourth (seconds) wheel and pinion, the tourbillon of Calibre FB-T.FC-R comprises 67 components assembled within a titanium carriage measuring 16.55 mm in diameter, and fixed to a perfectly hand-polished and chamfered arrow-shaped steel arch whose tip points towards the space between the barrel and the fusee. To poise the escapement’s unbalance, two 18-carat gold inertia-blocks ensure the uniform spread of the weights of this large-size tourbillon. This tourbillon contributes to earning Calibre FB-T.FC.R its chronometer title awarded by the Swiss Official Chronometer Testing Institute (COSC). One particular characteristic makes the tourbillon extremely distinctive: although it performs one rotation per minute, it does not indicate the seconds, since the Chronomètre Ferdinand Berthoud FB 1R.6-1 is one of the rare tourbillons to have a central sweep-seconds hand. Extremely long, slim and made of gilded bronze, the latter moves with remarkable accuracy and in a remarkable stable manner.
- Mechanical hand-wound Calibre FB-T.FC.R
- 15 ¾ lignes (diameter 35.50 mm – thickness 9.89 mm)
- 49 jewels
- Indications of the hours, minutes, seconds and power reserve
- Suspended fusée and chain constant-force transmission regulation
- 3 Hz low-frequency tourbillon with direct-drive seconds
- 53-hour power reserve
- Movement precision and rate accuracy certified by the Swiss Official Chronometer Testing Institute
- Octagonal case fitted with two (2) lateral portholes in glareproofed sapphire crystal providing a chance to admire parts of the movement
- Domed, arched and glareproofed sapphire crystal
- Screw-in case-back with glareproofed sapphire crystal
- Crown in carburised stainless steel with ceramic inlay
- Case in carburised stainless steel
- Diameter 44.00 mm, thickness 13.95 mm
- Water-resistant to 30 metres
- 20 pieces limited and numbered edition
- Regulator plate (dial) in black rhodium-plated nickel silver, satin-brushed by hand
- Hours indication on a sapphire disc at 2 o’clock
- Minutes subdial at 12 o’clock, cut-out, bead-blasted, rhodium-plated and bearing black Arabic numerals
- Flat seconds inner bezel ring, in bead-blasted black rhodium-plated nickel silver
- Power-reserve indication at 10 o’clock engraved on the regulator plate “0-1” and coloured in grey
- Hand-sewn rolled-edge double-sided alligator leather
- Titanium length-adjustable safety folding clasp
- Also available with pin buckle