Montblanc Heritage Chronométrie ExoTourbillon Rattrapante

Montblanc Heritage Chronométrie ExoTourbillon Rattrapante Limited Edition 8: A step forward in precision and performance
Montblanc enriches its Heritage Chronométrie Collection with a new ExoTourbillon Rattrapante limited edition of eight timepieces, combining the Maison’s patented ExoTourbillon with a monopusher split-second chronograph.

Heritage from the source

Since 1858, the Montblanc Manufacture in Villeret—established under the name “Minerva”— has been making ground-breaking calibres with regards to craftsmanship and performance. During the 1930s, the workshop’s fascination with recording elapsed time led to the production of split-second stopwatches, also known as “rattrapante” chronographs, from the French word “to catch up”. These precise stopwatches were able to measure intermediate times without interrupting the ongoing measurement of a longer elapsing interval.

Today, this same passion for fine watchmaking and measuring brief intervals of time with utmost precision continues to be the driving force behind collections such as the new Montblanc Heritage Chronométrie ExoTourbillon Rattrapante Limited Edition 8 that combines a monopusher split-second chronograph with the Maison’s renowned ExoTourbillon.

From the movement to the complications, the precision to the design, everything comes together to celebrate the heritage of Swiss fine watchmaking. The Montblanc Heritage Chronométrie ExoTourbillon Rattrapante Limited Edition 8 captures all the magic of watchmaking past, while never stopping to push the boundaries of innovation and performance with its handcrafted inhouse movement.

Distinguished design details

One of the major inspirations in the design of the Heritage Chronométrie Collection comes from the Minerva Pythagore timepiece. This wristwatch developed in 1948 featured a pure and elegant dial with applied Arabic numerals and indexes, as well as a precise minute scale. Housed in a slim polished gold case with curved horns and a stepped bezel, the Pythagore epitomized classic Swiss fine watchmaking. Today this historic piece provides the basis for the design of the new Heritage Chronométrie ExoTourbillon Rattrapante Limited Edition 8 with fine watchmaking details and finishings that respect the Pythagore design, while offering a new and contemporary rendition of a horological classic.

Delving into the dial

The solid gold dial of the Montblanc Heritage Chronométrie ExoTourbillon Rattrapante Limited Edition 8 features all the classic design codes associated with fine watchmaking, starting with a grey grené lower dial that enhances the different counters and subdials, and a vertical satinated finishing on the upper part of the dial that attracts the eye to the majestic ExoTourbillon. The ExoTourbillon itself is highlighted by a double infinity tourbillon bridge, which takes one week to be hand-bevelled and polished by Montblanc’s artisans. The three-dimensional dial is further enhanced by raised counters and subdials that include different finishings—the small seconds subdial and the 30-minute counter both feature an azuré motif in the centre and an opaline decoration on the external ring, while the second time zone and day/night subdials have been embellished with a sunray pattern. Completing this intricate dial are faceted sword-shaped hands for the hours, minutes, seconds, second time zone and chronograph minutes, and baton shaped hands for the day/night and chronograph seconds hands as well as applied red gold numerals and indexes. A final touch to this intricate dial is a refined grey satinated flange that is calibrated with a fifth-of-a second scale for the chronograph and that simultaneously shows the continually running minutes for utmost legibility.

An array of chronometric indications

In spite of the numerous details on the dial, legibility remains at the forefront of the design. The local time is indicated in the centre (hour and minute hands) with the small seconds in a subdial at 9 o’clock. Home time is shown (in hours) in the subdial at 6 o’clock, and is linked to the day/night indication displayed between 4 and 5 o’clock. A further subdial at 3 o’clock displays the 30-minute chronograph counter; while the chronograph’s seconds and split-second times are recorded via the chronograph hands in the centre.

When travelling, the new local time can easily be set by pressing on the corrector at 8 o’clock. Operating this corrector advances the central hour hand in hourly increments without affecting the minute hand or the home time at 6 o’clock.

Exemplary complications

Montblanc’s mastery of honouring traditional watchmaking is demonstrated perfectly in this new Montblanc Heritage Chronométrie ExoTourbillon Rattrapante Limited Edition 8 combining two of the most significant chronometric complications—the Maison’s patented ExoTourbillon and a monopusher split-second chronograph.

The ExoTourbillon complication, first introduced in 2010, was developed entirely in-house by the master watchmakers at the Montblanc Manufacture in Villeret. “Exo” is derived from the Greek for external or outside and refers to the screwed balance wheel, which is positioned outside of the tourbillon’s rotating cage. This innovated patented mechanical architecture allows the cage to be smaller in size and free of the weight of the balance wheel, saving 30 per cent more energy than a conventional tourbillon. The fact that the balance is positioned outside of the rotating cage also means that it isn’t affected by the inertia of the cage, therefore improving precision.

Another exclusive feature of the ExoTourbillon is the slower speed of its rotations. Conventional tourbillons typically complete one rotation per minute but the ExoTourbillon rotates once every four minutes. The slower rotational speed requires less energy from the barrel, yet produces the same compensating effect.

Thanks to the ExoTourbillon’s patented energy-saving construction, the tourbillon can be paired with a cleverly designed split-second chronograph function. Despite its mechanical complexity, this split-second function can work with the same barrel and the same power reserve as those of the basic chronograph movement—and can do so with greater precision than would be possible in a chronograph without the ExoTourbillon construction.

Split-second chronographs rank among the world’s grandes complications and are the pinnacle of the chronograph complication. Extraordinary mechanical complexity and nearly 70% more components than a conventional chronograph mechanism enable them to perform the useful function of momentarily halting the split-second hand to indicate intervals without interrupting the measurement of a longer elapsing interval by the chronograph’s elapsed seconds hand.

The Montblanc rattrapante complication works with two column wheels and a classic double clamp, which can be observed in motion through the transparent caseback. Once the chronograph complication is activated through the pusher integrated in the crown, both column wheels and the hand-bevelled levers, which are used to transfer the different commands, come into play. Thin steel springs that have been delicately curved then push the rattrapante clamps onto the split-second wheel, thus enabling the reading of the first measured interval when the wearer pushes the pusher located at the two o’clock position. Another push of the same pusher causes the clamps to spread apart so that the split-seconds hand catches up the chronograph’s elapsed seconds and keeps running with it. To stop and reset both chronograph and split second hands, the wearer pushes again on the pusher integrated in the crown.

Master watchmakers devote extreme care to the delicate components, which are extremely difficult to fabricate, finish and assemble. They are finely adjusted by only those with the highest level of expertise and experience.

The highest attention to detail

Particular attention has been paid to each and every detail in terms of precision, but also with regards to the aesthetic beauty of each component. The hairsprings are crafted entirely by Montblanc’s master watchmakers who measure the length of each spring by hand for utmost accuracy. The end of each hairspring is given an upward Phillips curvature and oscillates at the traditional pace of 18,000 semi-oscillations per hour (or 2.5 Hertz), thus enabling the chronograph to measure elapsed intervals to the nearest fifth of a second. A close look at the 2 o’clock position reveals the chronograph’s split-second column-wheel. In the centre of the calibre, aficionados will notice the artistically shaped rattrapante-lever, the split-second clamps’ mobile as well as their springs.

No detail on this manufacture manually-wound calibre MB M16.62 , with its 50-hour power reserve, has been overlooked—the edges of the components are bevelled, the surfaces are brushed, and the flanks bear fine, elongated embellishments. Their bright polishing contrasts beautifully with the Côtes de Genève on the bridges, glossy red jewels, and gold-plated wheels. All of these sophisticated and elaborate decorations have been executed entirely by hand—the only way to ensure the highest level of craftsmanship.

The Montblanc Heritage Chronométrie ExoTourbillon Rattrapante Limited Edition 8 comes in a 47 mm roundish case crafted in 18-karat red gold with a sapphire crystal caseback allowing a direct view on the beautifully hand finished calibre. Curved horns with characteristic facets, a stepped concave bezel, and a crown embedded with the Montblanc emblem, also contribute to the refinement of the timepiece.

Above and beyond

In order to ensure the highest performance and quality of its timepieces, Montblanc tests the whole Heritage Chronométrie Collection in its Montblanc Laboratory for over 500 hours. Called the Montblanc Laboratory Test 500, this quality control examination has been completely developed in-house and evaluates timepieces in numerous simulated real-life situations. Where many tests only control the movement, Montblanc tests the final watch, making this certification something truly unique in fine watchmaking.

The Montblanc Heritage Chronométrie ExoTourbillon Rattrapante Limited Edition 8 is also equipped with a high-quality alligator leather strap crafted by the Montblanc Pelletteria, the Maison’s own leather manufacture in Florence Italy, enabling Montblanc to offer the utmost quality. Montblanc is one of only a small handful of watch manufacturers that can equip their models with leather straps of their own fabrication.