Invention Piece 3 is a tribute to the third Greubel Forsey invention, the Tourbillon 24 Secondes, which consists of a single tourbillon cage inclined at a 25° angle and performing a rapid rotation in 24 seconds.
This stunning timepiece is powered by a mechanical hand-wound movement, Calibre GF 01N. Equipped with rapid rotating twin barrels, this calibre offers an autonomy of 72 hours.
Main features of this timepiece include Tourbillon 24 Secondes Incliné mechanism, hours and minutes display, seconds display and power-reserve indicator. The four gold plates are engraved with a portion of a personal message from Robert Greubel and Stephen Forsey.
The Tourbillon 24 Secondes uses a fast rotation speed and inclined angle to solve the problem of critical positions of the oscillator in relation to gravity. The 25° angle and the rapid rotation of the tourbillon cage significantly improve the chronometric performance of a system containing only one tourbillon, especially in stable positions.
The 43.50 mm diameter case in 18K gold or platinum is fitted with asymmetrical convex sapphire crystals on the front and rear sides.
The watch also features a lateral sapphire crystal window on the left side of the case, offering the glimpses of the movement.
The GREUBEL FORSEY Invention Piece 3 is available in a unique series of 33 timepieces: 11 each in 5N red gold, white gold or platinum.
Technical details
Model: Greubel Forsey Invention Piece 3
Movement
Mechanical hand-wound movement, Calibre GF 01n
Diameter: 36.40 mm; Thickness: 11.51 mm
Power reserve: 72 hours
Barrels: Rapid rotating twin barrels (1 turn in 3.2 hours) equipped with a slipping spring to avoid excessive tension
Balance wheel: Variable-inertia with gold mean-time screws (10 mm diameter)
Frequency: 21,600 vibrations/hour
Balance spring: Phillips terminal curve, Geneva-style stud
Main Plates: Nickel silver
Bridges: Nickel silver; “Message from the Inventor Watchmakers” relief engraved on gold plates
Gearing: Involute circle profile; Tangential inclined gear with profiled teeth, on fixed wheel and escape wheel pinion
Number of parts
– Complete movement: 370 parts
– Tourbillon cage: 87 parts
Weight of the cage: 0.39 g
Number of jewels: 42; Olive-domed jewels in gold chatons
Tourbillon cage
• Inclined at a 25° angle, 24-second rotation
• Cage pillars in Avional
• Titanium cage bridges
• Gold counterweight
Displays
24 hours
Minutes
Small seconds
72-hour power reserve on a sector
Case
In 5N red gold, white gold or platinum with asymmetrical convex sapphire crystal, 11 watches each
Diameter: 43.50 mm
Thickness: 16.06 mm
Transparent back with asymmetrical convex sapphire crystal
Lateral window with shaped sapphire crystal
Raised polished engraving of the name of the Invention on a hand-punched background
Gold security screws
Polished bezel and centre band with hand-finished straight graining
Hand-engraved individual number
Water resistance of the case: 3 ATM – 30 M – 100 FT
Crown: Gold with engraved and black lacquered GF logo
Hands
Hours (red triangle) and minutes (blue triangle)
Small seconds in flame-blued polished steel
Power reserve (red triangle)
Strap
Hand-sewn black and brown alligator leather with gold folding clasp, engraved with the Greubel Forsey logo
