Having pioneered the use of carbon-fibre reinforced polymer for watches cases with the Royal Oak Offshore Alinghi Team of 2007, Audemars Piguet (AP) is returning with a new generation of the material that debuts in the Royal Oak Concept Split-Seconds Chronograph GMT.

Based on the original model in old-school titanium, the new split-seconds chronograph has a carbon composite case made using Chroma Forged Technology (CFT) that allows for greater colour and patterning in the material. As a result, the CFT carbon case has the typical marbled appearance of carbon composite, but flecked with blue veins that glow in the dark.

Initial thoughts

The Royal Oak Concept Split-Seconds Chronograph GMT might seem like yet another variant of AP’s popular model, but it  is equipped with one of the brand’s latest movements, the cal. 4407. The movement boasts a modern, sophisticated construction, along with one of the most innovative implementations of the split-seconds mechanism in modern watchmaking.

The CFT carbon case dresses up the movement in more eye-catching attire, especially for those who found the first version in titanium too conventional. Although the new split-seconds only includes blue as an accent, the range of colours is essentially limitless since CFT carbon can be coloured in myriad hues. That means more colour variations are surely in the pipeline.

Though novel for AP, coloured or luminous carbon composite is not a new concept since the material been used for watch cases for several years now, even in affordable timepieces. So AP isn’t a pioneer with the material per se, but CFT carbon is no doubt higher quality than similar-looking materials in less expensive watches. AP has also patented the CFT manufacturing process.

More broadly, the material makes sense for the Royal Oak, since the line has historically been a proving ground for new materials. It also works well with the high-tech styling of the Royal Oak Concept, which is also large, making a lightweight case material ideal.

The first version launched last year had a titanium case

Coloured forged carbon

CFT carbon is fundamentally identical to conventional carbon composite, which AP terms forged carbon. It’s a mix of carbon fibre within polymer, creating a material that’s light and strong.

The specifics of the CFT process, however, are patented and unique to AP. The material starts with small pieces of carbon fibre that have been dyed, for this model in blue, but with any other colour possible as well. The pieces are then placed into a mould and arranged by hand, since their positions dictate the surface patterning of the finished material. Liquid resin is then poured into the mould.

The pieces of carbon fibre dyed blue in clear resin before baking

This process is done one layer at a time layer, slowing filling up the mould. Once full, the mould is then compress to squeeze out any air bubbles and then placed in an autoclave, essentially an industrial oven that bakes at high temperature and pressure. After ten hours in the oven, the result is a solid block of CFT carbon composite that can then be milled to form the case, which takes another six to eight hours.

CFT is AP’s first coloured forged carbon, a material that has superior resistance to humidity, heat, and shocks according to the brand.

Here it’s matched with a black ceramic for the bezel, crown, pushers, and case back, while the guards and inserts on the flanks of the case are titanium. The ceramic parts are finished in typical Royal Oak fashion, sporting a combination of satin and mirror-polished surfaces, while the titanium flanks are sandblasted.

While the material is new, the CFT carbon split-seconds retains the dimensions and designs of the earlier version, 43 mm in diameter and 17.4 mm in thickness, as well as a 50m water resistance rating.

Featuring a large date just below 12 o’clock, the open-worked dial has the chapter rings for the tachymeter scale and counters in blue to match the CFT carbon case. The blue chapter rings stand out against with the grey and black tones of the movement bridges, which partially reveal the chronograph and date mechanisms below the dial.

The counter at three o’clock is the GMT display with a pointer to indicate the hours of a second time zone, along with a round day and night indicator on the hub of the pointer. This can be adjusted with the coaxial pusher on the crown.

Rightly described by AP as “a feat of mechanical engineering” the cal. 4407 combines a flyback chronograph with split-seconds, GMT, and a large date. The movement offers 70 hours of power reserve and beats at 28,800 beats per hour (4 Hz).

The chronograph features a column wheel and vertical clutch, and also boasts a patented zero-reset mechanism that guarantees that the chronograph and the split seconds hand instantly and simultaneously reset to zero, thanks to a one-piece reset hammer.

But the most ingenious feature of the movement is the split-seconds mechanism that is mounted within the hub of the rotor. This not only makes the watch thinner, but allows the split-seconds to be mounted on the rear of the watch, instead of concealing it beneath the dial as is typically the case for self-winding split-seconds chronographs.

Key facts and price

Audemars Piguet Royal Oak Concept Split-Seconds Chronograph GMT Date
Ref. 26650FO.OO.D353CA.01

Diameter: 43 mm
Height: 17.4 mm
Material: Coloured forged carbon, black ceramic, and titanium
Crystal: Sapphire
Water resistance: 50 m

Movement: Cal. 4407
Functions: Hours, minutes, seconds, GMT, big date, and split seconds chronograph with flyback
Winding: Automatic
Frequency: 28,800 beats per hour (4 Hz)
Power reserve: 70 hours

Strap: Two rubber straps with titanium folding clasp

Limited edition: No
Availability: At AP boutiques and AP Houses
Price: Approximately CHF200,000

For more, visit Audemarspiguet.com.

Announced a month ago, IAMWATCH is a three-day event centred on independent watchmaking that encompasses lectures, classes, and panel discussions.

Taking place in Singapore from October 18 to 20 at the Edition hotel, Iamwatch has just revealed its programme for the event, which promises three full days – from breakfast to sundown drinks – of watches, watchmakers, and watch industry personalities. Entry is free but registration online is required.

Boldface names attending the event include independent watchmakers Felix Baumgartner, Konstantin Chaykin, Kari Voutilainen, and Rexhep Rexhepi; watch entrepreneurs Jean-Claude Biver, Manuel Emch, Maximilian Büsser, and Jean Arnault; and auctioneers Aurel Bacs and Sam Hines.

Konstantin Chaykin, Felix Baumgartner, and Rexhep Rexhepi

Each day begins with a breakfast hosted by industrial notables, including Maximilian Büsser on October 19. The breakfast is followed by a full schedule, including daily lectures about history and horology by historian David Rooney, author of About Time, a history of timekeeping.

Jean Arnault, Aurel Bacs, and Manuel Emch

Afternoons include classes on various topics, including Jean-Claude Biver on being a watchmaking entrepreneur – a pitch perfect match of speaker and subject if there ever was one.

Panel discussions take place daily as well, including one dedicated to independent watchmaking on the final day, October 20, moderated by myself with Felix Baumgartner, Kari Voutilainen, Rexhep Rexhepi as panellists.

Here’s a sample of daily highlights over the course of Iamwatch.

Day 1 – October 18

08:30 am: Breakfast with Felix Baumgartner of Urwerk and Rexhep Rexhepi of AkriviA

02:30 pm: Talk by illustrator Lee Yuen-Rapati on design and typography

03:30 pm: Class on watchmaking entrepreneurship by Maximilian Büsser

05:00 pm: Class on watchmaking entrepreneurship by Jean-Claude Biver

Jean-Claude Biver (centre), with James Marks and Pierre Biver

Day 2 – October 19

08:30 am: Breakfast with Maximilian Büsser of MB&F

10:00 am: Lecture by David Rooney on timekeeping throughout history

11:30 am: Panel discussion on collecting independent watchmaking with collector Firmin Li, Michael Tay of The Hour Glass, and Alexandre Ghotbi and Tiffany To of Phillips

02:00 pm: Panel discussion with young independent watchmakers comprising watchmakers Gaël Petermann, Rémy Cools and Theo Auffret, moderated by Jean Arnault of Louis Vuitton

Maximilian Büsser (left), with Serge Kriknoff of MB&F

Day 3 – October 20

08:30 am: Breakfast with Anton Suhanov, Florian Bédat, Gaël Petermann, Rémy Cools and Theo Auffret

10:00 am: Lecture by David Rooney on timekeepers’ “impact on our survival… long-term thinking and… future.”

02:00 pm: Panel discussion on authenticity in independent watchmaking with Felix Baumgartner, Kari Voutilainen, and Rexhep Rexhepi, moderated by SJX

05:00 pm: Closing party

Both the complete three-day programme and registration are available on Iamwatch.com.

Iamwatch is open daily October 18-20 from 11:00 am-08:00 pm and takes place at the Singapore Edition.

The Singapore Edition Hotel
38 Cuscaden Road
Singapore 249731

This was brought to you in partnership with The Hour Glass.

Having already explained the more traditional horizontal clutch (or lateral coupling), we now look forward to the more modern vertical clutch. This is found in some of the most famous chronographs in contemporary watchmaking, including the Rolex Daytona with the cal. 4131 (pictured above), Patek Philippe Nautilus with the CH 28-520, and Audemars Piguet Royal Oak Chronograph with the cal. 4401.

Arguably the most advanced type of chronograph coupling mechanism, the vertical clutch as it is known today was debuted in 1969 by Seiko in the 6139 chronograph. But the concept can be found in late 19th century pocket watches, and even the inexpensive Pierce Chronographe of the 1930s. Today it is practically the default choice for new chronograph constructions.

Equipped with the vertical clutch, the Patek Philippe CH 28-520 in the Nautilus Travel Time Chronograph ref. 5990/1A

Like its horizontal counterpart, the vertical clutch serves as the mechanical link between the chronograph mechanism and the going train of a movement, allowing power to flow from the going train to the chronograph, which then allows the chronograph to run. While it fulfils the same function, a vertical clutch works differently from the horizontal equivalent, a distinction that comes with its own set of advantages and disadvantages.

How it works

A chronograph vertical clutch is similar to the clutch found in the manual transmission of some automobiles. The clutch of an automobile enables the intermittent connection between the engine’s flywheel (which delivers torque and angular velocity) and gear box. This will be familiar to drivers of manual transmission cars: clutch in and the connection is broken, allowing for a gear change; clutch out after shifting gears, and the connection is resumed. 

The vertical clutch of a chronograph performs the same function, providing an on-demand connection but between the going train of the movement and the chronograph mechanism.

The vertical clutch assembly in the Rolex cal. 4130. Image – Rolex

Although the specifics vary across calibres, any vertical clutch is made up of the same basic components as shown in Figure 1: a flywheel (yellow) geared to (or even part of) the going train; a cone (grey) that is linked to the chronograph seconds mobile, and vertically tensioned by a spring (red); a pair of pincers (blue) that engage with the cone, lifting or lowering the cone.  All these components share the same axis. 

Figure 1. Simplified cross-section of a vertical clutch

The vertical clutch assembly of flywheel (yellow), tension spring (red), along with the pincers (blue), are illustrated from an overhead view in Figure 2, which is extracted from the Swiss patent associated to the Breitling B01, which also shows the broader architecture of a modern chronograph movement.

Figure 2. A section of the Breitling B01; note the structure of the pincers. Source – Swiss patent CH710205B1 filed by Breitling

Thanks to the tension spring underneath, the cone is sprung towards the flywheel, so its tendency is always to move upwards. When the chronograph is disengaged, the two pincer arms close in, lowering the cone (along with the chronograph seconds mobile and its associated hand), separating it from the flywheel. The cone then remains stationary while the flywheel rotates freely, driven by the going train.

When the chronograph is engaged (Figure 3), the chronograph control organ (typically a cam or column wheel) spreads the pincers away from the cone, allowing the cone to rise, thanks to the tension spring below, and make contact with the flywheel.

The cone is now connected to the flywheel and energy flows from the going train to the chronograph, causing the chronograph to run. The flywheel drives the cone at the rate of one revolution per minute, with the two components rotating together as one. The surfaces of the cone and flywheel can be coated in abrasive, which increases the security of the engagement and prevents slipping.

Figure 3. Vertical clutch engaged, with cone raised and engaged with flywheel

When the chronograph is stopped, the pincers close in against the cone, pushing it down and swiftly breaking its engagement with the flywheel. This disconnects the energy flow from going train to chronograph, while the mobile is kept stationary under tension by the pincers, causing the chronograph seconds hand to freeze instantaneously. For this reason, a vertical clutch chronograph doesn’t require the dedicated braking lever that is mandatory with a horizontal clutch.

The vertical clutch performs energy transmission, but also serves a role in the chronograph function. The chronograph seconds mobile (which is generally made up an axle, the clutch cone and its tension spring, a heart-shaped reset cam, and possibly an additional gear or finger) runs the elapsed minute counter as well, causing the elapsed minute hand to advance by one for every 60 seconds passed. This counting of minutes can be semi-instantaneous or jumping (with a finger), or “dragging” (if achieved with an additional gear).

Compared again the horizontal clutch

The vertical clutch is widely regarded as more efficient and a better performer than the classical horizontal clutch, explaining why majority of new chronograph calibres employ a vertical clutch. In fact, only new calibres that incorporate a horizontal clutch are either haute horlogerie constructions that do so for aesthetic and historical reasons, like the Vacheron Constantin cal. 3200, or movements that are essentially remakes of vintage calibres, like the Omega cal. 3861.

The truth of this simply reflects the fundamental physics of the vertical clutch. Because of the pincers and cone, it operates with very little friction, while also suffering little inertial loss of energy, since there are no intermediate gears that consume energy.

An example of a classical horizontal clutch in the Omega cal. 3861, which is descended from the Lemania cal. 1872/1873.

There is also no lateral meshing of wheels, a sometimes problematic process that can degrade the gears. A lateral clutch also usually requires manual adjustment of the depth of engagement between the meshing wheels, which is unnecessary in a vertical clutch.

With the up and down motion of the cone, all energy transfer happens seamlessly, with no imperfect engagement between the components.  For the same reason, a vertical clutch engagement is more secure and reliable, because the connection can’t come undone in the case of shock.

Patek Philippe introduced the CH 28-520 in 2006 inside the ref. 5960P and marketed it as one of the rare calibres that would still keep good time with the chronograph left running continuously, thanks to the vertical clutch

All of these mechanical advantages also translate into a practical upside for the wearer: a chronograph endowed with a vertical clutch can be left running indefinitely, with no undue wear on any of the components. In fact, a vertical clutch chronograph can be engaged continuously with negligible deterioration in timekeeping.

Even repeatedly starting and stopping a vertical clutch chronograph results in little amplitude loss in the balance, since the flow of torque from the gear train to the escapement is largely uninterrupted with the vertical clutch engagement.

Originally launched in 2019 as a fundraising exercise for the Musée International d’Horlogerie (MIH), the Gaïa wristwatch is returning for the museum’s 50th anniversary this year. The MIH is marking the occasion with a pair of watches, the Gaïa Series III and Gaïa 50th Anniversary, both limited editions that will help fund restoration work and promotional activities at the museum.

The two watches share the unique design of earlier Gaïa editions, but now the dials are engraved. Notably, the Gaïa 50th Anniversary (pictured above) has a guilloche dial that’s hand made by Georges Brodbeck, a veteran guillocheur whose workshop was acquired by Voutilainen two years ago.

The Gaïa Series III with a laser engraved dial

Initial thoughts

As with the earlier Gaïa watches, the new pair are a great way to support one of Switzerland’s leading watch and clock museums. But the Gaïa is not just a charity project, it is an appealing and well-priced watch.

The price has risen slightly, from CHF2,900 for the original to CHF3,400 for the Gaïa III, but the increase is modest relative to the watch industry as a whole, and the watch remains a value buy.

The Gaïa anniversary is twice the price at over CHF5,000, but still value considering the hand-made guilloche dial. It’s one of the handful of watches in this price range with a traditional engine-turned dial, plus it has an unusual time display and case. The closest comparison is the Louis Erard Excellence that is less expensive but makes do with a stock case, movement, and dial.

Georges Brodbeck

Geometric styling

The new Gaïa models are nearly identical to the earlier versions that were first in blue and then black. All of the watch is made in the region surrounding MIH, with each component made by a local specialist, ranging from Singer for the dials to Stila for the cases. The design is the work of Atelier XJC, which tweaked the design slightly for the latest pair.

Compact at 39 mm wide and under 10 mm high, the steel case features distinctive angular lugs reminiscent of vintage “wire” lugs. The details of the case are more elaborate than on most watches in this price range.

The original Gaïa watch, which shares the same case as the new pair

Inside is a Sellita SW400-1, a no-frills but reliable movement. The movement is conventional, but instead of hands, time is indicated by discs, giving the Gaïa an unusual face. Hours shown in a window across the top of the dial and minutes in the centre.

The case back is solid save for a window that echoes the hour display on the front, through which the rotor can be seen as it oscillates

The clean design of the watch is inspired by the MIH building, a Brutalist structure inaugurated in 1974 that also inspired the dial motifs on the new Gaïa watches.

Finished in a dark blue similar to that found on the first Gaïa, the dial of the Series III is laser engraved with a linear pattern inspired by the formwork marks on its concrete structure.

On the other hand, the circular pattern on the 50th Anniversary is more abstract. It is inspired by ensō, a hand-painted circle that represents clarity of mind and enlightenment in Zen Buddhism. Engine turned on a clean, silver dial, the pattern is meant to evoke the structure of the MIH premises.

The motifs on the Gaïa III (left) and 50th Anniversary

More intriguing is the 50th Anniversary edition, which shares the same case and movement, but boasts a solid-silver dial with traditional guilloche.

The concentric lines are engine turned by Mr Brodbeck, who does the guilloche freehand and without a template, meaning each engraved line starts and ends at a different level. As a result, each of the guilloche dials across the 50-piece edition are different.

Mr Brodbeck at work

Key facts and price

MIH Gaïa Series III and Gaïa 50th Anniversary

Diameter: 39 mm
Height: 9.74 mm
Material: Stainless steel
Crystal: Sapphire
Water resistance: 30 m

Dial: Brass coated blue and laser engraved for Gaïa III; solid silver with guilloche for 50th anniversary

Movement: Sellita SW400-1
Functions: Hours and minutes
Winding: Automatic
Frequency: 28,800 beats per hour (4 Hz)
Power reserve: 38 hours

Strap: Appel vegan leather with steel pin buckle

Limited edition: 100 pieces for Gaïa III, and 50 pieces for 50th anniversary
Availability: Direct from MIH online or at museum shop
Price: CHF3,400 for Gaïa III; CHF5,050 for the 50th anniversary (prices exclude tax)

For more, visit Montremih.ch.