Transparent sapphire crystal is the material traditionally used for scratch-resistant watch glasses. This very hard and homogenous material also boasts amazing acoustical properties that Chopard has succeeded in leveraging: typical minute repeater gongs are made of steel or gold segments which vibrate when struck, producing their characteristic sound. The L.U.C Full Strike is unique in that it is equipped with sapphire gongs. Moreover, Chopard has opted to step things up a notch, since these gongs form part of a coherent set.
|The minute hammer|
|The minute hammer being set in the movement|
Finally, the L.U.C Full Strike astonishes by the intensity of its chime. This is not a goal in itself for Chopard, which would never seek to achieve it to the detriment of sound quality. Throughout the 16 seconds that the watch takes to strike 12:59, it chimes in a uniform manner, a result that is extremely hard to achieve and in itself represents an important horological accomplishment.
In music, silence is as important as the notes themselves. For a minute repeater, silence is equally important and Chopard has developed the L.U.C Full Strike with this in mind. The rotations of the strike governor – the component that gives the striking mechanism its rhythm – are visible at 8 o’clock. While this part may sometimes emit a humming sound, that of calibre L.U.C 08.01-L is entirely inaudible. While components used for the striking mechanism sometimes make a clicking sound at the end of the tune, the L.U.C Full Strike does no such thing. Finally, it resolves one of the most disturbing problems faced by a minute repeater: the silence between the last hours stroke and the first quarters stroke, which may vary according to the specific quarter-hour to be struck.
In simple terms, the minute repeater sequence comprises one time-window for the hours, another for the quarter-hours and a third for the minutes. A chime is thus generally punctuated by long silences, during which the watch owner must wait and may in fact wonder whether the watch is still working. The structure of calibre L.U.C 08.01-L enables it to skip these silences automatically. Its hours, quarters and minutes gear trains are superimposed and mutually drive each other. When one has completed its task, it automatically triggers the next, maintaining a constant cadence however many strokes are to be chimed subsequently.
On one side of the calibre, the barrel, going train and regulating organ form a timekeeping ensemble with a 60-hour power reserve certified by the Swiss Official Chronometer Testing Institute (COSC). In this respect, the L.U.C Full Strike meets the demands imposed by Karl-Friedrich Scheufele, co-president of Chopard, who wanted the L.U.C collection to comprise Haute Horlogerie watches with certified precision. Contrary to tradition, the minute repeater mechanism is placed on the dial side and is thus entirely visible.
The L.U.C Full Strike steel hammers feature an individually modifiable striking force, thus making it possible for the watchmaker to perform fine adjustment of the acoustic intensity.
The L.U.C Full Strike is equipped with two barrels. Both are equipped with a slipping spring, as used in self-winding movements, in order to ensure that winding operations are not impeded by an overwound spring, and thereby protecting them against any risk of snapping. One stores up the energy required for time measurement, and the other that needed for the minute repeater. The L.U.C Full Strike therefore does not draw the energy required for the chime from a winding lever such as is generally found on the caseband. The energy is instead stored in a dedicated barrel enabling the movement to chime “the longest time” (12:59) 12 times in a row. The barrels are recharged by means of a large-diameter rose gold crown coupled with a differential gear, which transmits the force imparted by the hand towards the appropriate barrel, according to the direction in which the crown is wound.
The L.U.C Full Strike is equipped with a special system for indicating the twin power reserves, composed of two coaxially fitted hands. The first gilded one indicates the movement power reserve, while the other blue one indicates the number of chimes that can be activated. The latter indication is not there for information purposes only, since it also serves as a basis for one of the many security systems protecting the watch.
A minute repeater mechanism is a system of interactions that is unparalleled in watchmaking. Numerous movement parts are in motion and this implies equally numerous risks of breakage. Chopard has therefore equipped Calibre 08.01-L with three security devices protecting it from any handling mistakes. The striking mechanism power reserve is coupled with a semi-toothed wheel. When the reserve drops too low, it deactivates the minute repeater chime, thus ensuring that the watch cannot sound fully, due to the lack of energy.
Moreover, in order to maximise the striking mechanism power reserve, an ingenious patented device has been incorporated into the coupling-clutch of Calibre 08.01-L. During coupling and uncoupling, the regulator does not rotate, and only when everything is in its appointed place does the striking mechanism actually consume energy.
During the chime itself, the crown is disconnected from the movement, thereby making it impossible to perform any time-setting that could damage the movement. The activating pusher built into the crown is also deactivated at this time, since a second attempt to trigger the mechanism might otherwise force the striking mechanism coupling-clutch.
Breakage is not the only kind of risk facing a minute repeater movement, which may also chime imperfectly. Chopard has therefore created additional security devices guaranteeing the regularity of each sound indication. Information is picked up from the snails via the beaks on each rack, but the information is not directly transmitted via these racks as is traditionally the case, but instead via ratchet-wheels that activate gathering-pallets. This principle results in a gear ratio serving to increase security and thus ensure a regular tempo. This arrangement generally used for the hours has been extended to the quarters and minutes in this calibre.
Chopard has also resolved the issue of irregular sound intensity. To avoid the last strikes being too weak, the ratchet-wheels are coaxially arranged so as to ensure the hammers are smoothly and consistently raised and thus maintain their constant striking force on the gongs. Moreover, a flexible link between the hours and quarters ratchet-wheels guarantees a constant tempo between the last hours stroke chimed and the first quarters stroke, however many quarters need to be sounded.
With a total of seven security devices, the L.U.C Full Strike achieves a high degree of sophistication. The watch is preserved from risks of breakage. This omnipresent concern for durability and quality is the unmistakable signature of Chopard Manufacture.
In keeping with the L.U.C watch design codes, the L.U.C Full Strike features a vertical satin-brushed caseband creating a striking contrast with the polished bezel and case-back. All the inscriptions on the latter are hand-engraved and the case is made from 18-carat Fairmined rose gold. This label guarantees that Chopard has sourced this gold from a cooperative whose operations are certified as ethical, fair and sustainable.
All the components of Calibre 08.01-L are meticulously finished, be it with circular graining, straight graining or a Côtes de Genève motif. They are all meticulously hand-chamfered. The mainplate and bridges are made from nickel silver, a noble metal that can tolerate no scratches or workmanship errors. This material is non-treated and appears in all its natural subtly golden grey beauty through the sapphire case-back of the L.U.C Full Strike.
Model: L.U.C Full Strike
20-piece limited edition, Ref. 161947-5001 – In 18-carat “Fairmined” rose gold
18-carat “Fairmined” rose gold
Total diameter: 42.5 mm
Thickness: 11.55 mm
18-carat rose gold crown with L.U.C logo: 8.50 mm
Vertical satin-brushed caseband
Polished bezel and case-back, hand-engraved case-back
Exhibition back fitted with glare-proofed sapphire crystal
Mechanical hand-wound:L.U.C 08.01-L
Number of components: 533
Total diameter: 37.20 mm
Thickness: 7.97 mm
Number of jewels 63 jewels
Frequency: 28,800 vph (4 Hz)
Power reserve: 60 hours
Mainplate and bridges in non-treated nickel silver
Bridges adorned with the Côtes de Genève motif
“Poinçon de Genève” quality hallmark
Dial and hands
Gold dial with opaline silver-toned base
Finely snailed small seconds
Blue and black transfers
Gilded Roman numerals
Gilded Dauphine-type hours and minutes hands
Gilded baton-type small seconds and watch movement power-reserve hands
Blue baton-type striking mechanism power-reserve hand
Railway-type minute track engraved under the sapphire crystal
Functions and displays
Minute repeater striking on the sapphire crystal and sapphire gongs (patented system)
Central display of the hours and minutes
Small seconds display at 6 o’clock
Concentric display of the watch movement and striking mechanism power reserves at 2 o’clock
Strap and buckle
Strap in hand-sewn double-sided CITES-certified alligator leather, dyed with plant pigments
18-carat rose gold pin buckle