release
The Double Tourbillon Technique is an entirely original and innovative interpretation of Greubel Forsey's first fundamental invention, the Double Tourbillon 30°. It is a timepiece with a boldly assertive character and a totally unique architecture.
The Double Tourbillon Technique is a case study in precision mechanical watchmaking with the sapphire crystal acting as a portal through which to observe the mesmerising workings of the intricately interlocking parts. The eye is naturally drawn from one gear to the next, enabling careful observation of each separate element.
A true work of technical art
With the Double Tourbillon Technique, Robert Greubel and Stephen Forsey have created a
truly stunning timepiece that is faithful to their philosophy of technical visibility. Each and every element of the mechanism is enhanced and displayed without overshadowing others.
At the heart of the timepiece is the Double Tourbillon 30° mechanism ; however, to perpetuate the art of horology and contribute to its 21st century development, several additional technical
elements have been added, including four fast-rotating co-axial barrels guaranteeing 120 hours of autonomy.
Admirers can even enjoy the sight of the barrels rotating while winding and unwinding. Coupled to these barrels is the visible spherical differential that drives the power reserve indicator. The hours are displayed on a transparent sapphire crystal ring fitted inside the inner circumference of the bezel to ensure full visual access to the astonishingly three-dimensional depth of the mechanism. Transparency is also reflected in the luminous open-worked signature Greubel Forsey hands and both the power reserve indicator at 3 o'clock and sub-seconds dial at 9 o'clock are strikingly enhanced by their red triangular pointers.
A powerful personal message
By virtue of its fully visible mechanism, the Double Tourbillon Technique is a showcase for Robert Greubel and Stephen Forsey's unique blend of technical mastery coupled with superb aesthetic finishing. The timepiece reinforces their commitment to absolute quality and fine craftsmanship, also expressed in the discreet message from the inventor watchmakers engraved around the case band.
These highly personal words convey Robert Greubel and Stephen Forsey's total dedication to their art and their contribution to horological advancement through fundamental research, the sophisticated architecture of their movements and their relentess pursuit of optimal timekeeping.
Double Tourbillon Technique
Mechanical hand-wound movement, Calibre GF 02s Double Tourbillon 30°, Hours and minutes display, Outer Tourbillon 4-minute rotation indicator, Inner Tourbillon 60 Second rotation indicator, power-reserve indicator.
Patented Movement Movement dimensions
-Diameter: 38.40 mm -Thickness: 12.15 mm
Number of parts
-Complete movement: 385 parts -2 Tourbillon cages: 128 parts -Weight of the two cages: 1.17 g
Number of jewels
-43 -Olive-domed jewels in gold chatons
Power reserve 120 hours
Barrels-Four coaxial series-coupled fast-rotating barrels (1 turn in 3.2 hours), equipped with a slipping spring to avoid excess tension
-Gold nickel-palladium finished cover with relief engraving
Balance wheel Variable-inertia with white gold mean-time screws (10.70 mm diameter)
Frequency 21,600 vibrations/hour
Balance spring-Phillips terminal curve -Geneva-style stud
Main Plates Frosted nickel silver, polished bevelling, black chromed finish
Bridges Frosted nickel silver, polished bevelling, nickel-palladium finish, gold nameplate bearing the watch number
Gearing-Involute circle profile -Conical gearing with corrected profile
Inner Tourbillon Inclined at a 30° angle, 1 rotation per minute
Outer Tourbillon-1 rotation in 4 minutes -Hand-bevelled and openworked cage pillars -Solid gold counterweight
Displays-Hours and minutes -Small seconds -4-minute Outer Tourbillon rotation indicator -120-hour power reserve on a sector
Exterior Case material and finishes
-In 5N red gold, white gold or platinum with convex sapphire crystal -Transparent back with convex sapphire crystal -Raised polished engraving of the name of the Invention on a hand-punched background -Gold security screws -Nameplates with text screwed to the sides -Three-dimensional lugs secured with screws -Hand-engraved individual number
Case dimensions
-Diameter: 47.50 mm -Thickness: 16.84 mm
Water resistance of the case 3 ATM - 30 M - 100 FT
Crown Gold with engraved and black lacquered GF logo
Dial-Sapphire hour markers -Small seconds and power-reserve indicators in gold
Hands
-Hours and minutes in gold -Small seconds, Power reserve (red triangles) -Sapphire 4-minute indicator
Strap Hand-sewn black, brown, dark blue, grey or burgundy alligator leather with gold folding clasp, engraved with the Greubel Forsey logo
