Jaeger-LeCoultre

So here is finally coming the first and perhaps the most fascinating new watch from Jaeger-LeCoultre this year?

1833-2008, that's 175 years of history to celebrate so the task is huge

The launch of the Gyrotourbillon 1 a few years back in 2004 was a great time in Jaeger-LeCoultre's history. The Gyrotourbillon was indeed an instant revelation of the innovative potential of the "Grande maison". The following years saw the birth of several great watches like the Master Minute Repeater, the Grande Complication a Triptyque, the Amvox2, The Duometre a Chronographe, the Master Tourbillon, the Master Compressor Extreme Lab on the complication side, but also the Squadra range, the Diving range or the expansion of the Reverso 8 Days range.

Jaeger-LeCoultre Reverso Gyrotourbillon 2

It would be far from seeing the truth to consider this Gyrotourbillon 2 as a Reverso cased Gyrotourbillon 1!  In fact this watch nearly only keeps the Gyrotourbillon principle, here applied with several innovations in a new calibre.

A fifth Reverso Tourbillon

The first and main difference with the Gyrotourbillon 1, and also in my opinion the most appealing new characteristic of this calibre 174 is its cylindrical balance spring with end curves. This kind of balance spring is totally new in wrist watches even if John Arnold patented this kind of helical spiral in 1882 (some references also date this patent to 1776) and if it was even apparently invented much earlier by Robert Hooke.

Such cylindrical (or helical) spring supposedly improves chronometry as it is easier to make it isochronous.

A heat blued cylindrical balance spring

So far only marine chronometers and a few pocket watches have been equipped with such balance spring.  The reasons were that it is complex to manufacture and particularly to miniaturize. In fact its geometry goes well with the form of the Gyrotourbillon whose tourbillon cage has the necessary third dimension to house this voluminous balance spring.

Calibre 174 on dial side

The Gyrotourbillon combines two intertwined tourbillon cages, the first inner cage doing one rotation in 18.75 seconds and the second outer cage in 1 minute. This combination on 2 axes set at a 90° angle creates the ellipsoidal movement of the regulator that is said to isolate this very regulator from the gravitational effects on the rate in any position. While the Gyrotourbillon 1 needed 2 minutes to take all positions, this Gyrotourbillon 2 will need 5 minutes.

Calibre 174 on back side

Once again everything has been done to ensure the best timing to this calibre. The large size 14 carat gold balance wheel regulated to 4htz, or 28800 vph, has a 12.5 mgXcm² and is adjusted through gold inertia blocks arranged around its rim.

A horologically glamorous blue colour

The cylindrical balance spring has a rectangular section.

The heat blued cylindrical balance spring

The two final curves are chosen to allow a perfect breathing and a consequent isochronism. I have not been able to know the name of these curbs. Jaeger-LeCoultre has used existing curbs, but not Phillips curbs. The spring is pinned in a traditional triangular stud and the stud holder is secured with two screws for a safe fix.

The Gyrotourbillon 1 balance spring

The difference of geometry between the two Gyrotourbillon is particularly obvious if you compare these two drawings. It also shows that consequently the cage is not exactly the same.

The Gyrotourbillon 2 new geometry

Looking at these cages below it looks like a torture cage for the balance wheel but it is apparently a magical treat to forget gravity!

Horology is getting more and more complicated

The new balance Wheel has open-worked arms to decrease the overall moving weight inside the cage. The 100 or so parts of the Gyrotourbillon apparel weight 3.4 grams (while the full calibre is 371 parts). The full spherical diameter of the aluminium cage is 10.85 mm.

The balance wheel

The dial side shows the hours and minutes through two heat blued hands on a sapphire dial at 12, and a close wheel on the left upper part of the dial shows the 24 hours. This is not a second time zone.

The dial side of calibre 174

The back side shows the power reserve indicator of 50 hours.

The back side of calibre 174

The watch has simple functions but once again that's the basic functioning that is improved.

The torque limitation device

The mainspring is fitted on top with a torque limitation device that limits the power reserve to 50 hours and that ensures that the watch is stopped before becoming un-precise. In fact I'm tempted to consider also this torque limitation device, coupled with the power reserve indicator like a torque indicator. As long as you make sure that the power reserve is between the two extremes you have a torque considered as optimal, or at least sufficient. Or in more pragmatic terms, with this device as long as the watch is running it has the desired torque!

The power reserve blued hand

The torque imitation device is quite nice and simple in principle. The principle is about two wheels turning together. One is concentric with the barrel, the other one is below the little bridge. They don't have the same number of teeth.

One is driving when the barrel is giving power to the main train, the other one is driving when the barrel is being wound. The driving one drives the other, in one direction or the other. Both have each a unique upper tooth and these two teeth can't cross. When they touch the device is stopped, either stopping the winding or the main train.

There's a patent applied for this device.

The back of the Gyrotourbillon 2 in its full glory

The power reserve indicator also has a little refinement. There's an additional hairspring to compensate the play in the gear train, so that the power reserve indicated is always the real power reserve in the main spring.

The main spring

The main spring is covered on top and below with sapphire parts to reduce friction.

The main spring in the calibre

The winding system is equipped with conic wheels.

The cannon-pinion wheel

The cannon-pinion wheel has a new and surprising design.

The cannon-pinion wheel is used to engage the main train to the cannon-pinion, i.e. to the hands. When the watch is running the wheel is attached to the cannon-pinion through sufficient friction. When the hands are set through the crown the friction between the cannon-pinion wheel and the cannon-pinion is not enough to make the main train be driven by the cannon-pinion. In some way the cannon-pinion is by force disengaged from the main train when the hands are set.

The cannon-pinion wheel in place

In the case of the Gyrotourbillon 2 the cannon-pinion wheel is slightly flexible and is not round when it is not engaged. This wheel has 5 arms, one being detached from the others.

When the cannon-pinion is engaged in the wheel the wheel takes its round shape and the movable fifth arm applies a force to the cannon-pinion so that the necessary friction is distributed all around the cannon-pinion.

The cannon-pinion wheel below the dial

There's also a patent applied on this new wheel design.

The awesome Reverso Gyrotourbillon 2

Obviously this amazing watch is not just a chronometric machine. It is somewhat a simple watch with little additional complication

The chronometric necessity of the seconds hand

Still it is a very beautiful watch, with a pure horological design, and also a very high level of finish not seen before on  a Jaeger-LeCoultre wrist watch.

Defintely not a design gimmick

The launch of the Gyrotourbillon in 2004, and several following upscale models, have necessitated the creation of a new finish department at the manufacture.

The highest level of finish

The « haut de gamme » finish department is in some way the legacy of the work done for years by master watchmakers like Sylvain Golay and his colleagues.

A new dimension of finish

The evaluation of the finish on this watch will necessitate an open approach to the new dimension broad by the Gyrotourbillon. This calibre is not just a pile of assembled pieces like every classical calibre is. The tri-dimensional Gyrotourbillon adopts a more modern approach than the more classical dial area finish.

The aluminium outer cage

You will please not forget that the watch shown is an early prototype and doesn't necessarily show the final finish.

Finish tools

The finish works is hand made but the hand is sometimes helped by motorized tools.

Wood and leather polish wheels

The tools can be very traditional like the polish tools in box wood or leather. The materials offer a very soft polish on some very small and sometimes light pieces.

Leather at work

The intangible dial and the large opening of the tourbillon cage show a complete view on the calibre parts. These parts are the style of the watch through their finish. That's why I wrote pure horological design.

Layers on the dial area, lack of field on the Gyro side

Re-entrant angles are everywhere, for the pleasure of the high finish fans !

Sharp finish

The finish is sharp and not rounded like it is often the case with Jaeger-LeCoultre. This is really the work of this new finish department and they even admit that they keep improving. Some coming Master Tourbillon watches may hopefully get the next step of finish to be at the top!

Close to the top

Frederick Henry Royce the co-founder of Rolls-Royce stated that "the perfection is no small thing but is made of small things". This watch is definitely a new step towards perfection for Jaeger-LeCoultre.

There's no small detail

Some bridges on the dial side are nailed, a first time for Jaeger-LeCoultre and a very pleasant result.

Nailed

The nails reinforce the visual effect of the sharp angles.

Nailed closer

The nickel silver bridges are also very nicely angled. The angles are polished to bring a third dimension to the pieces.

Even closer

So the watch is technically superb, shows an un-seen level of finish from Jaeger-LeCoultre, but is it a usable watch?

But is it too large

Let me be clear ! This is a usable watch. It is made for use. It is simple, precise, waterproof (30m), comfortable to wear with its integrated leather strap.

Tri-dimensionally fascinating on the wrist

This watch becomes perfect only on the wrist where it is supposed to be the time organ of your body!

Somewhat thick

Of course the Reverso Gyrotourbillon 2 is not an ultra thin. It is a thick watch. But it is not over thick, neither over large.

Fitting even my smallish wrist

This watch was very cleverly designed as its Reverso case is much more wearable than the Grande Complication a Triptyque.

If you can wear a Grande Reverso or a Squadra

In fact the reversing case is 14.5mm thick. The case and sapphire glasses have a standard Reverso appearance.

Extreme inside, classical outside

Due to the weight of the platinum reversible case the watch is fitted with a locking device like the Grande Complication a Triptyque.

A fascinating view on the wrist

The series will be strictly limited to 75 pieces in platinum.

You can wear it on the back side too

This amazing watch is certainly a satisfying tribute to the long history of the Grande Maison, from the pioneering spirit of the founder Antoine LeCoultre who invented the tools that allowed the production of more precise watches to the following integration in a complete manufacture.

A watch with substance

This rare watch may not be essential for many of the more than 1200 people working at Jaeger-LeCoultre (around 20% of the total of the Vallee de Joux workers), it will be an essential watch dream for many of us watch admirers and specially for the chronometry amateurs.

Who can say no thanks

As this Gyrotourbillon 2 will be more affordable than the first Gyrotourbillon I have little doubt that it will encounter an even larger success.

I would put it on my desk and spend hours looking at it

Around 2 thirds of the 75 Gyrotourbillon 1 have been delivered so far, but the production of the Gyrotourbillon 2 has already begun.

Gyrotourbillon 2 cases already made

Now it's time to decide already if you want it!

Time to decide

This watch will make a hit at this year's SIHH.

Or it will turn its back to you

Congratulations to Jaeger-LeCoultre for this outstanding timepiece.

Here is my all time favourite JLC!

Dje

ps : my sincere thanks to the Jaeger-LeCoultre teams who gave me some of their precious time while preparing the soon to be SIHH 2008.