This new edition of the Greubel Forsey Double Tourbillon Technique timepiece boasts a blue dial lay out. This new version is available in limited edition of 33 pieces in titanium, platinum or white gold.
Equipped with a hand-wound movement with patented tourbillon, this timepiece incorporates an inner tourbillon inclined at a 30° angle and revolving 1 rotation per minute and an outer tourbillon that revolves 1 rotation in 4 minutes.
The combination of the 30° inclination with the different rotational speeds of the two tourbillion cages improves timekeeping by averaging out positional errors due to gravity in all usual wristwatch positions, and especially in static positions.
In its dial side, the watch features a blue coloured multi-level synthetic sapphire hour ring with hour indexes and golden hour and minute hands with Super-LumiNova. In addition to the dazzling display of the two tourbillons, the dial also hosts a small seconds counter and a power reserve indicator.
Technical details
Model: Greubel Forsey Double Tourbillon Technique Blue Limited Edition
Limited edition of 33 pieces in titanium, platinum or white gold
Movement
Hand-wound movement with patented tourbillon
Double Tourbillon 30° • hours and minutes • small seconds • outer tourbillon 4-minutes rotation • inner tourbillon 60-seconds • power-reserve
Movement dimensions
• Diameter: 38.40 mm
• Thickness: 12.15 mm
Number of parts
• Movement: 396 parts
• Two tourbillon cages: 132 parts
• Weight of the two cages: 1.17 g
Number of jewels
• 43
• Olived-domed jewels in gold chatons
Chronometric power reserve
• 120 hours
Barrels
• Four 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
• Black finished 22k gold 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
• Nickel silver, frosted with polished bevelling and countersinks, straight-grained flanks, blue finish
Bridges
• Nickel silver, frosted and spotted with polished bevelling and countersinks, straight-grained flanks, blue finish
• Gold plate engraved with the individual number
Inner tourbillon
• Inclined at a 30° angle, 1 rotation per minute
Outer tourbillon
• 1 rotation in 4 minutes
• Hand-bevelled and open-worked cage pillars
• Gold counterweight
Gearing
• Involute circle profile
• Conical gearing with profiled teeth
Displays
• Hours and minutes
• Small seconds
• 120-hours power reserve on a sector
• 4-minutes outer tourbillon rotation
• 60-seconds inner tourbillon rotation
Exterior
Case
In titanium with convex synthetic sapphire crystal
Diameter: 47.50 mm
Thickness: 16.84 mm
Transparent back with synthetic sapphire crystal
Three-dimensional, variable geometry-shaped lugs, screwed fixing
Raised polished engraving “Double Tourbillon 30°” and “Greubel Forsey” on a hand-punched background
Gold security screws
Polished bezel, caseband with hand-finished straight graining
Two titanium plates, engraved, hand-finished with texts, screwed to the caseband
Engraved individual number
Water resistance of the case: 3 atm – 30 m – 100 ft (standard NIHS 92-20/SN ISO 22810:2010)
Crown: In titanium with engraved GF logo
Dial side
Multi-level synthetic sapphire hour-ring, galvanic growth hour indexes, engraved and lacquered inner tourbillon rotation indicator
Small seconds and power-reserve indicators in gold
Hands
Hours and minutes in polished gold, with Super-LumiNova
Small seconds, power-reserve (red triangles)
Engraved synthetic sapphire 4-minutes indicator
Strap and clasp
Black rubber or hand-sewn alligator
Titanium folding clasp, engraved with the GF logo
