Greubel Forsey Tourbillon 24 Secondes Architecture

Featuring a new convex conical frustrum case shape, the Greubel Forsey Tourbillon 24 Secondes Architecture watch boasts an atypical construction.

Equipped with a hand-wound calibre, its components are suspended in space, revealing a harmonious composition of surfaces, shapes and movements. The case showcases the spectacle within firstly through the large opening on the dial side, encompassed by relief-engraved Greubel Forsey values that inspired this creation.

Greubel Forsey Tourbillon 24 Secondes Architecture

While the case looks perfectly round when observed from the dial side, it reveals its convex shape from other angles, along with its large synthetic sapphire crystal ring which envelopes the entire periphery of the caseband.

This novel case design enables a comprehensive look at even the smallest detail of the high-end mechanical movement. The 354 parts of this Greubel Forsey hand-wound calibre are sculpted and arranged asymmetrically yet harmoniously. The polished titanium bridges immediately stand out from the frosted finish of the mainplate.

Tourbillon 24 Secondes Architecture

Positioned at 6 o’clock, the Tourbillon 24 Secondes mechanism has a large spherical and open-worked bridge, whose base remains hidden by design. In its form, the inclined escapement defies gravity, while in its function, it compensates for it. To solve the problem of critical positions of the oscillator in relation to gravity, the Tourbillon 24 Secondes uses a fast rotation speed in addition to a 25° inclination. These two elements combined contribute to excellent chronometric performance, especially in stable positions.

Greubel Forsey Tourbillon 24 Secondes Architecture

The barrel bridge at 10 o’clock boasts polished spherical surfaces, along with polished beveling and countersinks. The barrel cover is engraved, lacquered and circular-grained and contains three coaxial series-coupled fast-rotating barrels, one of which is equipped with a slipping spring to avoid excess tension. The caliber’s energy source provides 90 hours chronometric power reserve, indicated by a moving red triangle over a conical disk at 3 o’clock. It too is held in place by a beautiful polished titanium bridge.

Greubel Forsey Tourbillon 24 Secondes Architecture

The two large curved, openworked and polished steel hands mounted on a signature Greubel Forsey tripod bridge indicate the hours and minutes. The time indication is completed at 8 o’clock by a small second on a cylinder with polished flanks.

Greubel Forsey Tourbillon 24 Secondes Architecture

Made of titanium, the Greubel Forsey Tourbillon 24 Secondes Architecture will be limited to only 11 pieces in 2022, then to 18 pieces a year between 2023 and 2025 for a total of 65 exclusive timepieces overall.

Technical details

Model: Greubel Forsey Tourbillon 24 Secondes Architecture in Titanium

Case
Titanium and synthetic sapphire crystal
Three-dimensional, variable geometry bezel with raised engraved text
Synthetic sapphire crystal over the entire periphery of the caseband
Three-dimensional, variable geometry lugs, hand-polished with hand-finished straight graining
Transparent back with synthetic sapphire crystal
Titanium security screws
Raised engraving “Architecture 1” and “Greubel Forsey”
Caseband diameter: 47.05mm
Bezel diameter: 45.50mm
Height: 16.80mm
Water resistance: 5atm – 50 m – 164ft (standard NIHS 92-20/SN ISO 22810:2010)
Crown: Titanium, polished and frosted, with GF logo

Dial
Three-dimensional, variable geometry hour-ring, indexes with Super-LumiNova
Power-reserve indicator, circular-grained, engraved and lacquered
Gold small second indicator, circular-grained, polished flank
24-seconds tourbillon rotation indicator

Hands
Hours and minutes, curved profile, polished steel with Super-Luminova
Small seconds, red triangle
Power-reserve rack, circular-grained, polished bevelling, straight-grained flanks
24-seconds double-tipped, black anodised aluminium

Movement

Hand-wound movement with 2 patents
Overall diameter: 38.70mm
Thickness: 12.35mm
Number of jewels: 42
Olived-domed jewels in gold chatons
Frequency: 21’600 vibrations/hour
Power reserve: 90 hours

Number of parts
• Movement: 354 parts
• Tourbillon cage: 86 parts
• Weight of the cage: 0.38g

Barrels
• Three 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
• Engraved pattern with Greubel Forsey, lacquered, circular-grained

Balance wheel
• Variable-inertia with gold mean-time screws (10mm diameter)

Balance springs
• Phillips terminal curve
• Geneva-style stud

Bridges and main plate
• Titanium
• Frosted, polished bevelling and countersinks
• Polished spherical bridges, polished beveling and countersinks
• Three-dimensional centre bridge, frosted, polished bevelling and countersinks

Movement side
• Three-dimensional power-reserve bridge, frosted, polished bevelling and countersinks
• Tourbillon bridge, polished bevelling and countersinks, circular-grained
• Engraved pattern with individual number, circular-grained, straightgrained flanks

Tourbillon
• Inclined at a 25° angle, 24-seconds rotation
• Light alloy cage pillars
• Titanium cage bridges
• Gold counterweight

Gearing
• Involute circle profile
• Tangential inclined gear on fixed wheel and profiled teeth on escape wheel pinion

Displays
Hours and minutes
Small seconds
Power reserve on a sector
Tourbillon rotation

Strap and clasp
Non-animal material, rubber with text in relief, titanium folding clasp, engraved GF logo