GREUBEL FORSEY – Double Balancier Convexe Carbon Edition

GREUBEL FORSEY – CONVEXE Double Balancier Convexe Carbon 42.5 mm Limited Edition 2023

Greubel Forsey provokes a sensation unveiling its very first carbon creation. For the occasion, the Double Balancier Convexe takes on new dimensions with a smaller diameter of 42.5mm. This totally unexpected timepiece shares the Atelier’s boldness combining structural complexity with the style of a highly technical material.

Click , to see the large size. ▶ BIG FOTO  

Greubel Forsey delivers a new generation of carbon timepieces. The material becomes part of the Atelier's collections, offering collectors enhanced lightness and resistance.

Click , to see the large size. ▶ BIG FOTO  

Recognised and appreciated by collectors, the Convexe case fully benefits from this design choice. On the case back, its form perfectly meets the curve of the wrist. On the dial, a three-dimensional, curved profile allows the movement to fully express itself. Since carbon fibres are never combined twice in the same way, the design of each piece will also be unique, reinforcing the exclusivity of the timepiece.

Pressing carbon to its limits

It was no mean feat to produce the convexe carbon case. The carbon case, as developed by Greubel Forsey, requires pressure 8 times greater than average (16 tonnes applied to a convexe case, compared to an industry standard 2 tonnes). 

Click , to see the large size. ▶ BIG FOTO  

This mechanical effort makes it possible to obtain a much denser carbon for an almost identical weight, to be enjoyed by the collector.

Style at the service of performance

For Greubel Forsey, this specific technique opens up the possibility of executing fine watchmaking finishing by hand that affirm the Atelier’s identity and status. This is how you'll come to find finishes, from satin to matt and relief engraving on the Double Balancier Convexe, all complementing the natural work of the carbon fibres that Greubel Forsey has taken care to match with the converging lines on the convexe case. 

Click , to see the large size. ▶ BIG FOTO 

This is carbon deployed at its best, both flexible and solid, with fibres between 1 and 5 microns thick, perfectly defined and mastered.

One case, two versions

The timepiece has a considerably more modern feel, perfectly in line with the direction of the signature brand. This is also the reasoning behind the reduced diameter of 42.5mm on the Double Balancier Convexe.

Click , to see the large size. ▶ BIG FOTO 

Greubel Forsey demonstrates the power of these new carbon timepieces from the outset by offering its collectors two versions with strong assertive character. The first features a dominant iridescent green finish, with numerous rich blue hues to the main bridge incorporating the power reserve display, as well as the mainplate and the hour ring. This is complemented by a rubber strap in the same tone, creating a fresh feel and reinforcing the signature brand’s contemporary commitment.

Click , to see the large size. ▶ BIG FOTO  

The second version brings black to the fore, asserting the timepiece's elegant simplicity. The carbon fibre weaves a homogeneous, decidedly contemporary configuration. By contrast, the salient feature that stands out most is the hand-finished movement, with its mirror polishing, sharp internal angles, straight and circular-grained surfaces, and curved hands with luminescent tips. In both the green and black versions, the Double Balancier’s calibre exudes technicality and precision.

The majestic Double Balancier

A truly unique expression of this sixth Fundamental Invention, while the invention itself has never stopped evolving. Its prototype mechanism was patented in 2007. It was first proposed as part of an EWT (Experimental Watch Technology) project, in which the two regulating organs were superimposed and inclined at 20°. A second calibre of just six timepieces followed close behind, with the two regulating organs positioned on three-dimensional planes and inclined, this time at 35°.

Click , to see the large size. ▶ BIG FOTO 

In 2016, Greubel Forsey presented the invention in its current form: the two balance wheels are arranged side by side, inclined at 30°, and linked by a constant spherical differential visible between 6 and 7 o'clock. In each 4-minute period, it halves the margin of error and meets the performance, precision and reliability requirements that Greubel Forsey sets for all its timepieces.

Click , to see the large size. ▶ BIG FOTO  

In this unprecedented compact version with a diameter of 42.5mm, only 22 pieces will be produced in each variation of the Double Balancier Convexe carbon, with the first available from August 2023.

==================
 TECHNICAL DETAILS

Double Balancier Convexe Carbon Limited edition

Hand-wound movement with 2 patents
Double Balancier • hours and minutes • small seconds •
4-minutes spherical constant differential rotation • power-reserve

 Click , to see the large size. ▶ BIG FOTO  

Movement
Movement dimensions
• Overall diameter: 37.70 mm
• Thickness: 9.46 mm
Number of parts
• Movement: 371 parts
• Escapement platform: 2 x 70 parts
• Spherical constant differential: 30 parts
Number of jewels
• 50
• Olived-domed jewels in gold chatons
Chronometric power reserve • 72 hours
Barrels
• Two coaxial series-coupled fast-rotating barrels (1 turn in 3.2 hours), one of which is equipped with a slipping spring to avoid excess tension
• Relief-engraved text, circular-grained, green or black treatment, polished chamfer
Balance wheel
• Variable-inertia with gold mean-time screws (10mm diameter)
Frequency • 21’600 vibrations/hour
Balance springs
• Phillips terminal curve
• Geneva-style stud
• Anti-shock system with gold pin
Bridges and main plates
• Titanium
• Frosted, polished bevelling and countersinks, green or black treatment according to the version
• Multi-level, openworked centre bridge, polished bevelling and countersinks
Movement side
• Flat black polished steel differential bridge
• Gold plate with engraved limitation number, circular-
grained, polished bevelling and countersinks, straight- grained flanks
Escapement platforms
• Inclined at a 30° angle
• Steel, straight graining, hand-polished bevelling and countersinks
• Polished steel pillars
• Openworked steel balance wheel bridges, hand-polished bevelling and countersinks, flat black polished
Gearing
• Involute circle profile
• Inclined gear with profiled teeth on fourth wheel
Displays
• Hours and minutes
• Small seconds
• 4-minutes spherical constant differential rotation
• Power reserve on a sector

Exterior

 Case
• Carbon and titanium with curved synthetic sapphire crystal
• Three-dimensional, variable geometry-shaped bezel, hand-finished
• Profiled lugs, screwed fixing
• Transparent back with curved synthetic sapphire crystal
• Titanium security screws
• Raised engraving “Double Balancier” and “Greubel Forsey”
Case dimensions
• Caseband diameter: 42.50 mm
• Bezel diameter: 44.40 mm
• Case height: 13.75mm
• Height on synthetic sapphire crystals: 14.35 mm
Water resistance of the case
• Water-resistant 5 atm - 50 m - 164 ft (standard NIHS 92-20/SN ISO 22810:2010)
Crown • Carbon, hand-finished with GF logo
Dial side
• Three-dimensional, variable geometry hour-ring with engraved and lacquered minute-circle
• Three-dimensional, variable geometry hour indexes, polished, with Super-Luminova
• Power-reserve indicator, engraved and lacquered
• Differential rotation and small seconds indicators in gold
Hands
• Hours and minutes, curved profile, polished steel with Super-Luminova
• Power-reserve, 4-minutes and small seconds in polished steel, blued according to the version, flat
black polished head
Strap and clasp
• Non-animal material, rubber with texture in relief, titanium and carbon folding clasp, engraved GF

🔰 Limitation 
Limited Edition of 22 pieces.

-----------------------------
Press Release - 2023
-----------------------------
-------------------------------------------------
GREUBEL FORSEY SA
For further information: 
Communication Department 
press@greubelforsey.com – +41 79 194 2884
Eplatures-Grise -16 P.O. Box 670 
2301 La Chaux-de-Fonds - Switzerland
+41 32 925-4545
+41 32 925-4502
----------------------------------------------------------------------
www.facebook.com - Greubel Forsey
---------------------------------------------------------------------------
www.GreubelForsey.com