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Review of Zenith Academy Georges Favre-Jacot with specs and price

by Peter Chong on December 20, 2014
In 1864, Georges Favre-Jacot founded the manufacture Zenith in Le Loche at a tender age of only 22. To celebrate the 150 years of its founding, Zenith released the Academy Georges Favre-Jacot. A watch which is a amalgam of the skills within the manufacture.

 

The Zenith Academy Georges Favre-Jacot.

The Zenith Academy Georges Favre-Jacot.

 

At first look, the watch is visually impressive, with a very large cut out to show part of the movement. This large cutout in the dial makes the watch stand out. Typically dials feature a cut out to reveal a tourbillon, but in the case of the Academy, it reveals something far more rare: a  fusée and chain. Two magnificently polished bridges, hold the system in place, and stretching from one side to the other is the beautifully polished chain.

 

The layout and the aesthetic proportions of the relationship between the components of the dial is very pleasing. The dial itself has a very interesting texture which contrasts nicely to the polished bridges and applique markers.

 

The dial is a rather beautiful, white textured surface.  The cutouts prominently show the fusee and chain and the mainspring barrel.

The dial is a rather beautiful, white textured surface. The cutouts prominently show the fusee and chain and the mainspring barrel.

 

Two standout features set this watch aside as something special.The first necessitating the use of the second.

 

The High Beat movement

 

The first standout feature of this watch is the use of a 36,000 bph movement. This is quite common in Zenith watches, the most famous of which, their El Primero Chronograph movement utilizes this frequency. The high beat allows the movement to be more stable as the inertia in the balance to continue in its beat is higher. The negatives of using a high beat movement are that the lubrication tends to be less stable and secondly, the energy requirements are larger. Zenith have over the years mastered the savoir faire needed for the lubrication issue, and solved the second problem with a larger mainspring.

 

The movement side. The movement is in a traditional gilt finished, with the transmission wheels to the barrels polished and the bridges for the fifth wheel and balance also polished.  Finishing is quite good, with chamfering for the screws and jewel points. Note the sharp edges of the main plate and the nicely executed anglage on the plate's edge.

The movement side. The movement is in a traditional gilt finished. The transmission wheels to the base of the fusée and the bridges for the fifth wheel and balance appear to be made from maillechort. These provide a visual contrast and are polished.
Finishing is quite good, with chamfering for the screws and jewel points which are in gold chatons. Note the sharp edges of the main plate and the nicely executed anglage on the plate’s edge. Of note also is the opening for the click and the massive click spring.

 

A larger, more powerful mainspring brings issues of its own. The mainspring discharges its torque over time in accordance to Hooke’s Law. When the barrel is fully wound, the torque discharged into the movement train is high. As the barrel unwinds, the torque reduces, resulting in an uneven torque being delivered into the movement train. The larger the mainspring, the larger the difference from max torque when fully wound to min torque when fully unwound. As the torque changes, the rate in which the escapement beats may also change correspondingly. Further, when fully wound, a large mainspring may be so powerful, that the escapement banks, and does not keep a regular beat.

 

Hence, for very large mainsprings, a method of equalizing out the torque is needed. Here is where the second standout feature of this watch comes into play.

 

The fusee, fully wound. Note the chain is magnificently made, each link polished.

The fusee, fully wound. Note the chain is magnificently made, each link polished. Note also, at the center of the fusée’s apex, is the maintaining power mechanism. This mechanism allows torque from the mainspring to continue to be delivered to the movement train when the user is winding the watch. When the watch is being wound, the chain traverses from the bottom to the apex, and in an opposite direction to when it is discharging. Without the maintaining power mechanism, the movement will be forced into reverse.


The Fusée and chain system

 

Two methods have been favoured by watchmakers over the centuries to provide a constant force to the escapement. The first is the fusée and chain, and the second is to incorporate a remontoir d’égalité mechanism into the train.

 

The fusée fully unwound.

The fusée fully unwound.

 

Zenith decided to use the fusée and chain system in the Academy. This is more straightforward method, and rather common feature in pocket watches from circa 1850-1920.

 

The method is very effective, with the fusée acting like gearing: increasing the torque delivered to the train as the power from the spring wanes. As the mainspring torque wanes when the mainspring discharges, the chain traverses the fusée from its apex when the mainspring is fully wound, to the larger base. The shape of the fusee is calculated to precisely offset the torque changes. This allows the mainspring torque to be equalized as it is delivered to the movement train.

 

The chain itself is a challenge to manufacture:

 

Detail of the Zenith chain.

Detail of the Zenith chain.

 

Construction is much alike a bicycle chain. As shown in the photograph above, the links are rivetted to the each other. This presents a special problem as the chain needs to be flexible enough to coil itself around the fusée and barrel, but rigid enough so that the power is transferred efficiently, This problem is described by watchmakers as libre san jeux. And requires special techniques to solve the problem. These special techniques are beyond the scope of this article, but the author has written at length about it in his book: “A. Lange & Söhne: The Pour le Mérite Collection”.

 

Detail of the bridge holding the balance. We particularly love the curved design. The execution of the bridge is also top notch.

Detail of the bridge holding the balance. We particularly love the curved design. Note the parachute like device, held by a blued screw over the KIF equipped end stone. The execution of the plate opening to the bridge is top notch. Note the beautiful gleaming edges of the anglaged sides of the bridge below the engraving “HIGH FREQUENCY”. On the other hand, the bridge, though nicely executed, seem to be lacking anglage and it appears the edge finish of the bridges are left a bit natural. The escape wheel, blocked by the bridges in this photograph is in silicon.

 

A. Lange & Söhne first incorporated a fusée and chain system in a wristwatch with their Tourbillon Pour le Mérite, announced in 1994. Subsequently the fusée and chain is found in all Lange watches within the Pour le Mérite class. At time of writing, there are 4 such models. Other manufacturers who have used the same fusée and chain system are Breguet in their La Tradition Tourbillon and Cabestan in all their watches. The Romain Gauthier Logical 1’s chain system lacks a fusée and is just a transmission system.

 

The first use of the fusée and chain system in Zenith was in the Christophe Colomb Hurricane. And we see it here, executed very well in the Academy. Overall, this is a magnificent watch, showcasing the technical knowhow of Zenith in an aesthetically pleasing package.

 

The watch sits very nicely on the wrist. We find the visual impact of the open dial to show the fusée and chain and barrel to be captivating and a key attraction.

The watch sits very nicely on the wrist. We find the visual impact of the open dial to show the fusée and chain and barrel to be captivating and a key attraction.

 

Specifications from Press Release

 

ACADEMY GEORGES FAVRE-JACOT

Retail price in Singapore: S$105,500

  • Fusee and chain transmission linked to the barrel to ensure constant force

  • 797 parts
  • Cosc-certified movement

  • 150-piece limited edition

MOVEMENT

El Primero 4810, hand-wound

Calibre: 16½ ‘‘‘ (diameter: 37 mm)

Thickness: 5.90 mm

Parts: 222 (+ 575 for the fusée and chain system)

Jewels: 30

Frequency: 36,000 vph (5 Hz)

Power reserve: 50 hours minimum

FUNCTIONS

Hours and minutes

Fusée and chain transmission linked to the barrel

Small seconds between 7 and 8 o’clock

Power reserve between 4 and 5 o’clock

CASE, DIAL AND HANDS

Material: 18-carat rose gold

Diameter: 45 mm

Thickness: 14.35 mm

Glass: cambered sapphire crystal glareproofed

on both sides

Water resistance: 3 ATM

Dial: grained silver-toned

Hour-markers: gold-plated rhodium, facetted

Hands: blued

STRAP AND CLASP

Brown alligator leather with protective rubber lining

Triple-blade folding clasp in 18-carat rose gold

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