Girard-Perregaux Calibre GP 4800 Review
The Girard-Perregaux Calibre GP 4800 is the latest movement from the esteemed Manufacture and represents the distillation of know-how amassed over 234 years. Within the horological landscape, the Swiss marque’s vast array of talents is rare. Widely known as a movement specialist, Girard-Perregaux’s expertise encompasses design, development, manufacturing and assembly. Indeed, the Maison is considered a master of each discipline; talents it has skilfully employed with the creation of its latest movement, the Girard-Perregaux Calibre GP 4800.
Introduction
A movement must harness energy to repeatedly perform a choreographed series of manoeuvres. Despite its compact dimensions, due consideration must be given to torsional strength. To be of use, a movement should be precise and its rate should remain relatively linear, whether the mainspring is fully wound or partly tensioned. Ideally, the wearer should be able to remove the watch from the wrist and return several hours later to find it still ticking, obviating the need for setting the time again. It’s essential that a movement is reliable and simple to service. All the above criteria must be considered to the nth degree. The creation of a wholly new movement is not an everyday event and both the time required and the necessary investment are not inconsequential.
Girard-Perregaux Calibre GP 4800 – the importance of aesthetics
Measuring 11 ½ lignes (25.60 mm) with a thickness of 4.28 mm, the Calibre GP 4800 is sufficiently compact to fit within a modestly sized housing, meeting the growing demand for smaller case dimensions.
A clean-sheet design, the Girard-Perregaux Calibre GP 4800 not only fulfils the many practical considerations outlined above but is also beautiful. Indeed, since creating the legendary Tourbillon with Three Bridges of 1867, the Manufacture has repeatedly designed and made movements that proffer an abundance of eye-appeal and this latest calibre proves no exception.
Upholding GP tradition, the Calibre GP 4800 features three prominent bridges spanning its silver-toned form: a balance bridge, a gear train bridge and a barrel bridge. The architecture of the movement has been designed with due consideration to symmetry. When viewed with the balance at 12 o’clock, both the left and right sides of the movement mirror one another. The skeletonised balance bridge is supported with two screws, conferring stability as well as imbuing the movement with a sense of visual harmony.
A skeletonised rose gold oscillating mass sits above the bridges, harvesting energy from the natural motion of the wearer’s wrist to energise the mainspring. The design of the skeletonised oscillating mass (aka rotor) affords superior views of the finely decorated movement components below (see later).
Girard-Perregaux Calibre GP 4800 – silicium escapement
While Girard-Perregaux has a long history of making watches featuring its own in-house movements and clearly respects many of watchmaking’s traditions, it does not dwell in the past. Indeed, throughout the last 234 years, the brand has repeatedly shown an extraordinary ability to innovate. The Calibre GP 4800 features up-to-the-minute know-how with its silicium escapement. The escape wheel, pallet lever and roller are made from the lightweight material. Silicium is light, resistant to wear and unaffected by magnetism, all useful characteristics for watchmaking. Silicium can also be optimally shaped to maximise efficiency and chronometric performance. For example, the pallet lever is skeletonised, reducing mass and therefore mitigating energy consumption. Furthermore, it is one part, obviating the need for pallet jewels to be secured in position with shellac (or similar). This delivers production efficiencies and, most importantly, product consistency.
Image above – pallet lever
Image above – escape wheel
Image above – roller (mounted on the balance)
Girard-Perregaux Calibre GP 4800 – a variable inertia balance
A balance spring is affixed to the balance staff at one end using a collet, while the other end is attached to the stud. With most watch movements, the balance spring passes through two curb pins mounted on a curb adjuster. The action of moving the curb adjuster either towards or away from the stud alters the ‘effective length’ of the balance spring, making the watch run faster or slower.
The Calibre 4800 features a variable inertia balance. Again, employing a collet and a stud; however, the effective length of the balance spring remains fixed. The rate is adjusted by tightening / loosening four white gold screws recessed within the rim of the balance wheel. Despite being more time-consuming to regulate, this approach allows the rate to be set more precisely, provides greater stability and improved resistance to shocks.
A reinforced barrel accommodates a powerful mainspring that delivers significant torque to the gear train and ultimately the escapement and regulating organ. Indeed, the balance wheel has an inertia of 8mg per cm², which, together with the variable-inertia balance, mitigates the adverse influence of shocks. Furthermore, the increased torque delivers enhanced stability, thereby aiding precision. From the barrel to the regulating organ, all parts have been optimised to deliver performance.
Girard-Perregaux Calibre GP 4800 – whisper-quiet winding system
Featuring a new, upgraded winding system, the oscillating mass is mounted on a ball bearing set with ceramic balls. This is combined with a shock absorber system that reduces noise, ensures smooth operation and counters shocks, improving long-term durability. The motion of the oscillating mass is transmitted through a ball-bearing clutch system, energising the mainspring when rotating in one direction and disengaging in the opposite direction.
Girard-Perregaux Calibre GP 4800 – ten types of finishing
There are several reasons for finishing (‘finissage’). For example, when parts are made using CNC (Computer Numerical Control), bar turning or EDM (Electrical Discharge Machines), small burrs or signs of machining can be left behind. This extraneous material must be removed to ensure the movement runs smoothly without any impediment. Furthermore, in the rarefied heights of Haute Horlogerie, there is an expectation that all signs of machining will be removed.
The Calibre GP 4800 is endowed with ten types of finishing. The three bridges are adorned with Côtes de Genève, feature diamond bevelled edges and include engraved text in rose gold (5N). Contrasting the traditional appearance of the bridges, the mainplate, contemporary in appearance, is sandblasted and engraved with the words ‘Silicium Escapement’. The heaviest and bulkiest part of the oscillating mass runs in a channel (‘trottoir’) encircling the bridges and, on this occasion, is endued with snailing.
‘Girard-Perregaux’ and the brand’s logo adorn the oscillating mass. Presented in relief and executed in polished form, they contrast with the sandblasted surfaces positioned adjacent. High-gleam polishing extends to other movement components, sitting in concert with additional forms of decoration such as chamfered wheels and sunray finishes. Each aspect of the movement is the product of protracted consideration and draws on the immense talents of the brand’s craftspeople.
Closing remarks
Girard-Perregaux has designed, developed and made the Calibre GP 4800, employing expertise it has amassed over 234 years. The movement represents the culmination of years of work and represents a significant financial investment on the part of the brand. The creation of the Calibre GP 4800 has involved due consideration being given to precision, reliability and beauty. Moreover, the Maison has also given thought to future requirements, hence the Calibre GP 4800 has been designed so that it can be used as a base calibre and combined with additional complications if needed.
In an arena where many companies talk about making ‘in-house’ movements and sometimes use the term ‘Manufacture’ loosely, Girard-Perregaux clearly has the legitimacy to use both expressions. Indeed, when examining the specification of the Calibre GP 4800, it merely serves to reinforce what many watch aficionados already know: this Manufacture crafts movements brimming with virtue.