If three watches constitute a trend, then measuring milliseconds, or 1/1,000s of a second, is a trend. Two watch brands, each with high-speed horological histories, have launched mechanical chronographs claimed to be capable of accurately measuring 1/1,000s of a second. Last year, TAG Heuer debuted its Mikrotimer Flying 1000 Concept Chronograph, followed this year by the even faster Mikrogirder. At SIHH this year, Montblanc launched its own millisecond-measuring marvel, the TimeWriter II Chronograph Bi-Fréquence 1000, which employs a unique approach to splitting seconds.
In a sense, development of Montblanc’s high-speed chronograph began in 1916. That’s when Minerva launched its first 1/100s-of-a-second stopwatch. Acquired by Richemont in 2006, Minerva was a true manufacture, known for chronographs and pilots’ watches. In 2007, Richemont decided that Minerva would produce movements for Montblanc, and the following year, Montblanc launched the “Fondation Minerva” to create the TimeWriter series, consisting of extraordinary timepieces developed with independent watchmakers. The first piece in the series – Metamorphosis – was launched in 2010. The newest piece, the Bi-Fréquence 1000, is the latest TimeWriter creation.
Because of Minerva’s long experience producing high-speed chronographs, Montblanc recognized that constructing a chronograph capable of measuring 1/1,000s of a second over a useful interval presented four challenges:
1. The movement must be precise, and simply increasing the frequency of the balance wheel would not work, because engaging the chronograph would cause a significant loss of amplitude, reducing precision.
2. A gear train that advanced 1,000 times per second would be subjected to wear and tear that would reduce the movement’s longevity.
3. The chronograph indications must be legible. Measuring to the nearest 1/1,000s of a second means nothing if the elapsed time to the third decimal cannot be easily read.
4. The chronograph must be useable in the real world, meaning it must be able to measure intervals longer than just a few minutes.
(Click on watch photos for larger images.)
To meet these challenges, Montblanc teamed up with independent watchmaker Bartomeu Gomila, who had an ingenious idea for measuring 1/1,000s of a second. Gomila’s concept was based on a childhood toy – a simple hoop kept rolling with regular taps from a stick. The result is a chronograph with a unique system for splitting seconds into ever-smaller units, and an unusual way of displaying those units.
Any discussion of the Bi-Fréquence must begin with an overview of the dial layout. At first glance, an observer might note that Montblanc has failed to satisfy its self-imposed legibility requirement. In an interview, Montblanc’s managing director of watches, Alexander Schmiedt, acknowledged that the Bi-Fréquence is “not an easy watch.” However, as we learned firsthand, a brief orientation yields an understanding of, and even an appreciation for, the dial’s clarity.
As shown in the photos, the time of day is displayed by the small, white, center-mounted hour and minute hands. The chronograph is a monopusher design, with the start, stop and reset functions controlled by the single pusher located between the lugs at 12 o’clock. The pusher’s location is a nod to the early Minerva 1/100s-of-a-second stopwatches.
The chronograph elapsed seconds and minutes are displayed co-axially at 6 o’clock. The longer, red-tipped hand displays 60 elapsed seconds on the white outer track, and the shorter solid red hand displays elapsed minutes on the red inner track. The 1/100s of a second are indicated by the center-mounted red hand with arrow tip. This hand makes one trip around the dial per second, displaying the 1/100s of a second increments clearly. The 1/1,000s-of-a-second display is located in a large, curved window at 12 o’clock. Inside the window, the letter “N” and the numerals 0 to 9 indicate the status of the display and denominate 1/1,000s of a second. When the chronograph is running, the small, red, triangle-shaped indicator at the bottom of the window remains motionless, pointing to the red “N.” At the moment the chronograph is stopped, the red arrow instantly jumps to indicate the elapsed 1/1,000s of a second. Putting all of these chronograph indications together, in the image below, the total elapsed time is 2 minutes and 19.139 seconds.
The chronograph has its own mainspring barrel, the power reserve of which is visible on the dial at 3 o’clock. The winding crown is bi-directional; turning it one way winds the timekeeping mainspring and the other winds the chronograph spring barrel. The chronograph’s autonomy is 45 minutes when fully charged, and the reserve can be increased by winding the crown while the chronograph is running. Montblanc says the chronograph’s long power reserve helps maintain the balance wheel’s amplitude, which increases timekeeping precision. Another interesting feature: the chronograph escapement has its own regulator, which is visible in the image of the movement through the caseback.
Now that we comprehend the dial, we can discuss what lies behind it. Or at least we can discuss what we know, because Montblanc has not yet fully revealed all of the technical details.
Like TAG’s Mikrotimer, Montblanc’s Bi-Fréquence employs two separate mainsprings, oscillators and escapements – one for keeping the time of day, and one for the chronograph. The timekeeping balance wheel oscillates at a leisurely 18,000 vph, or 2.5 Hz. The chronograph balance oscillates at 360,000 vph, or 50 Hz. Those of you keeping score at home may be wondering how a chronograph running at 50 Hz can measure 1/1,000 of a second, since 50 Hz is the frequency required to measure 1/100s of a second. How does Montblanc measure milliseconds with such a “slow” oscillator? That’s where Gomila’s childhood hoop comes in.
Typically, there is a direct relationship between the speed or frequency of a chronograph’s escapement and the fractions of seconds it can measure. The famous Zenith El Primero movement beats at 5 Hz, or 36,000 vph, and it can measure 1/10s of a second. That’s because the balance wheel makes 10 vibrations, or back-and-forth rotations, per second. Multiply that by the 60 seconds in a minute, then again by the 60 minutes in an hour, and you have the 36,000 vibrations per hour rate. If you multiply the El Primero’s rate by 10, that yields 50 Hz, or 360,000 vph, which can measure 1/100 of a second. Ten times faster still is 500 Hz, or 3.6 million vph, which can measure 1/1,000 of a second. That’s what TAG’s Mikrotimer does.
Montblanc takes a very different route to achieving millisecond resolution for its watch. Its chronograph escapement operates at 50 Hz, so it can measure 1/100s of a second. However, Montblanc adds a special wheel that it calls the “thousandths wheel,” or mobile de millième in French. This wheel is Gomila’s childhood hoop. The “hoop” receives an impulse from the chronograph gear train (the childhood stick) that causes the mobile de millième to rotate 10 times per second. Quoting Montblanc, the rotating mobile de millième “provides the resolution with which hundredths of a second can be further subdivided into sets of 10 increments.”
Montblanc has not yet revealed the exact nature of the interaction between the chronograph gear train, the mobile de millième, and the 1/1,000-of-a-second indicator. That may be because there are two primary and 24 subsidiary patents pending on the system that translates a lower frequency into timekeeping resolution that would normally require a higher frequency. Schmiedt noted that Montblanc’s translation principles will work with other frequencies.
We can report that the prototype watch we examined started, stopped and reset perfectly, and the 1/1,000s of a second display appeared to function as described. Of course, it is not possible to discern with only a pair of eyes whether 1/1,000s of a second are actually being measured. Montblanc says it has tested the watch with a stroboscope to ensure that it is in fact measuring the milliseconds correctly.
Schmiedt did confirm that the movement is fully integrated, and that it is an original, “clean sheet of paper” design – no existing plates or modules were used in the construction. The chronograph functions are controlled by a two-level column wheel: one level guides the start, stop and zero-return functions; the other level controls the 1/1,000s. The mobile de millième does not engage with the gear train in the traditional manner, so it does not increase wear and tear on the movement. Montblanc considers the movement to be a world first – not for measuring 1/1,000s of a second, but for the way in which the 1/1,000s are measured.
Though the chronograph is fast, the reset function is not. It appears to operate in slow motion. This design feature allows the owner to appreciate the complexity of the watch in a subtle and compelling way.
According to Schmiedt, development of the movement took a team working at Villeret two and a half years. Gomila spent 10 months in Villeret last year building the prototype himself. Montblanc’s constructors created the parts, and Gomila assembled everything himself.
The movement has 472 parts, including 45 bearing jewels, and measures 38.4 by 10.6 mm. It is housed in a white gold case that measures 47 by 15.1 mm.
Schmiedt says the Bi-Fréquence meets each of the four challenges recognized by Montblanc: it precisely measures 1/1,000s of a second, it does not suffer wear-and-tear-related issues, it is easy to read, and the chronograph’s power reserve makes it useable in real life.
A total of 36 pieces will be produced, priced at $305,900. Montblanc’s target is to deliver the first piece by the end of the year, and to deliver one or two pieces per month after that. The series is not yet completely sold out, but according to Schmiedt, “a large part” of the production is pre-ordered. Schmiedt expects that it will take about two years to deliver all of the pieces. Apparently, measuring milliseconds is not a fast process, after all.
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