AESTHETIC APPEAL WITH A LONGER SERVICE LIFE

In haute horlogerie, various components in the watch movement such as bridges, cocks, plates and cogs are painstakingly hand decorated or given special surface treatments that add a touch more luxury. While decorative polishing serves a purely aesthetic purpose, gold plating can increase a product’s service life and functionality.

 

An IWC is not only a precision instrument for showing the time but also the ideal piece of jewellery to adorn the wrist of a man of the world. The dial, of course, takes centre stage in any mechanical luxury watch. 

But the true connoisseur also finds consummate beauty in places not immediately visible. “Various components in the movement, such as the plates, bridges and cocks, are ornately decorated or finished. Together with complications like the perpetual calendar or tourbillon, these decorations are an important part of haute horlogerie,” explains Christian Satzke, Project Manager Movements at IWC. In many timepieces from Schaffhausen, some of these decorative elements can be seen through the glass back of the case.

DECORATION IS A TRADITION IN SCHAFFHAUSEN

The French term “finissage” embraces a wide range of finishing techniques, some of them several hundred years old. They include various types of grinding, polishing or embossing but also traditional engraving techniques such as chasing or engine turning. Galvanic coatings are also widespread. “While decorative polishing serves a purely aesthetic purpose, we use gold-plating to improve the service life and functionality of the component in question,” adds Satzke.

IWC looks back on a long tradition of decorating its movements. Even the earliest Jones calibres were ground, polished and engraved, despite the fact that the decorations were not even visible in the finished pocket watches. Ornamentation experienced a renaissance at the height of the quartz crisis, when the Schaffhausen company turned its sights to haute horlogerie. From then on, alongside the technical innovations being made, optical beautification of the high-quality movements became a much greater priority.

—IWC Calibre Jones Pattern E, Lépine. It is the only known example of this Lépine pattern E movement. The attractively decorated movement is typical for the high quality Jones movements. (Property of Hannes A. Pantli / Heinz Hasler Photographer)”
—Detail of the calibre 98295 with the Geneva stripes also known as “Côtes de Genève”

DECORATIVE POLISHING AND ENGRAVING IS A FEAST FOR THE EYES

The most common forms of decoration are various types of grinding. “We use grinding or polishing techniques to apply patterns to the bridges, cocks or plates,” explains Satzke. A frequently occurring decoration is Geneva stripes, as they are known, or “Côtes de Genève”, which as a rule are series of parallel lines. Other popular forms include “circular graining”, comprising of densely packed circles, or sun pattern guilloche work, in which circular lines radiate from the centre. Often, a combination of different types of grinding is applied to a single watch movement. Take the 52610 calibre in the Portugieser Perpetual Calendar, for instance. Here, the calendar platform and the movement plate are finished with circular graining while the barrel bridge is decorated with circular-ground Geneva stripes.

Artistic engravings are another important decorative element. Apart from the “International Watch Co.” wordmark, other details such as the calibre and movement numbers, the number of jewels and the maximum power reserve are also engraved on the company’s in-house movements. The craft of elaborate hand engraving in Schaffhausen is inseparably linked with the name of Wolfgang Siegwart, who was head engraver at IWC in the 1990s. Using his burin and engraving stylus he left his personal signature on every Grande Complication and ensured that every single example was unique in its own right. Equally unforgettable was the Da Vinci Tourbillon Four Seasons, limited to 20 timepieces, on whose dial Siegwart engraved four exquisitely executed figures.

A THIN COATING IMPROVES FUNCTIONALITY

While the appeal of decorative polishing and engraving is primarily visual, galvanic coatings also improve the functional qualities of the part in question. Components made of steel or brass are placed in an electrolytic bath and covered with an extremely thin coating of precious metal. “Gold-plating a cog, for instance,” says Satzke, “reduces friction and increases the mechanism’s overall efficiency.” But this type of finishing also provides effective protection against wear and tear and oxidation. Gold- and nickel-plating are frequent features of IWC-manufactured movements. Some parts are also rhodium-plated. A galvanic coating of rhodium – a member of the platinum group of metals – not only makes parts extremely hard and corrosion-resistant but also gives them an attractive colour.

Various components in IWC's in-house movements are lovingly hand decorated
—Blued screws are used to secure both the bridges and the solid gold rotor in position.

Other finishing techniques have both an aesthetic and a functional component. Chamfering, for instance, is used to take off the rough edges on bridges and plates. “Parts that have been chamfered simply look like they are much better quality. But the process also gets rid of minute metal slivers that can break off and form resin with the oil,” says Satzke, describes the advantages of the process. The same applies to burnishing: pressure-polishing pivots improves their appearance and at the same time reduces the friction between the pivots and their bearings.

With the launch of the new Portugieser family, IWC has reintroduced the “blueing” process to its range of finishing techniques. The technique involves heating steel screws to a temperature of 290 degrees Celsius for a prescribed time and then allowing them to cool. The annealing process not only makes the steel harder and more rugged but also gives the screws a gorgeous, deep cornflower blue appearance. In the 52610 calibre, for example, blued screws are used to secure both the bridges and the solid gold rotor in position.

SKELETONIZATION LAYS BARE THE HEART OF A WATCH

Finally, a very rarely practised form of decoration is known as “skeletonization”. Here, any unnecessary material in the plates, bridges and cocks is simply cut away. The results can be fascinating. The interplay of the various parts of the movement can seldom be seen so clearly. Making a skeletonized watch, however, is extremely complicated. This is possibly the reason so many apprentice watchmakers choose to make one as the practical project – their “masterpiece” – for their final examinations. Skeletonized watches from Schaffhausen are a rare phenomenon: Only the IWC Portugieser Minute Repeater Skeleton Ref. 5241 and the Portugieser Tourbillon Mystère Skeleton Ref. 5043 have been produced in this transparent version.

The various decorations and types of finishing, some of which are unbelievably intricate, take the already high standards of haute horlogerie to another level. It is manifested in the fact that even components the owner will never actually see, such as the calendar platform for the perpetual calendar found in the 52 calibres, are lovingly decorated. “For me, techniques like these are a clear indication of the heights to which IWC aspires in the art of quality watchmaking,” is how Satzke sums it up.

—Portugieser Tourbillon Mystère Skeleton Ref. 5043

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