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Devoted to Fine Watches


In recent Issues, QP has devoted plenty of space to the resurgence of ambition on British watchmaking and QP58 is no exception as we recount the debut of M [...]


QP Magazine Current Issue #58
Stars in their Eyes: IWC

Stars in their Eyes: IWC

By Tracey Llewellyn

If you're looking for a mega-complicated timepiece, IWC may not be the first brand you think of. But if a constant force tourbillon, a perpetual calendar, sidereal time display and a heavenly astronomical module is what you're after - and you are prepared to wait a year for it - then the new Portuguese Sidérale Scafusia is the watch for you.


While those of us who haven't yet 'been there, done that' still act like a child at Christmas when faced with the unveiling of a brand new watch, the more jaded journalists out there tend to treat launches with a general air of nonchalance. But when 80 members of the international press were herded en masse into a Schaffhausen lecture theatre in September this year, the buzz in the room suggested that what we were about to see was something pretty special. Step forward the new Portuguese Sidérale Scafusia - the most exclusive and complicated watch ever created by IWC Schaffhausen.


moodIWC's most complicated watch to date, the Portuguese Sidérale Scafusia.


Summed up by Georges Kern, CEO of IWC: "The Portuguese Sidérale Scafusia is a universal work of art and the result of ten years' research by a team of engineers, watchmakers and scientists. They have succeeded in combining solar time and sidereal time on a single dial. From the front, this fascinating masterpiece is a classical Portuguese watch, from the reverse side an astronomical instrument and, on the inside, a milestone in the art of haute horlogerie."


It was a decade ago, that IWC decided to create something unique, with the culmination of those discussions being the decision to combine watchmaking and cosmology in a way never seen before. On earth, time is measured by the length of the average solar day, i.e. the average time between the sun's passage over a given meridian, which is almost exactly 24 hours. But for astronomers, the factor that counts is the sidereal day, the reference for which is a distant star perpendicular to an observation point at the beginning and end of a set period, i.e. the time taken for the earth to complete a rotation around its own axis, which, taking into account its arc around the sun, takes approximately 23 hours 56 minutes and 4 seconds.


mainThe patented constant force tourbillon is the beating heart of the piece, its sophisticated mechanism ensures that the amplitude of the balance, and thus the watch's accuracy, remain exceptionally constant.


There is nothing new with watchmakers incorporating sidereal time into their watches, indeed the concept itself is as old as civilization, but what marks this watch out from others that show sidereal time is the number of complications in the piece - a perpetual calendar, twilight/sunrise/sunset indicator, astronomical module and, the pièce de résistance, a constant force tourbillon.


Evolving brief

The original brief back at the start of the millennium was to develop the tourbillon, a task that involved a whole team of engineers and according to IWC Board member, Hannes Pantli, an achievement that could never be attributed to one person. But, as often happens, the brief evolved over the decade that followed, with sidereal time being introduced five years ago, bringing in even more collaborators.


The watch consists of over 500 components and takes over three weeks just to assemble. Only one watchmaker is currently able to put the pieces together - small wonder then that only eight watches can be made per year. The front of the piece features the solar time, the sidereal time (both can be set independently), power reserve and a very large tourbillon as seconds display - the tourbillon being the most difficult module to perfect due to the tiny tolerances involved,.Situated at 9 o'clock, it is positioned over almost a quarter of the dial and features a constant power mechanism, which ensures a steady trickle of energy to the balance, increasing the efficiency of the new in-house 94900 calibre hand-wound movement.


celestialEach astronomical module is different meaning that the customer is not only the owner of an extraordinary watch but also has his own personalised constellation showing the night sky at the geographical position of his choosing.


But, despite the technical achievement of the tourbillon, it is the reverse of the watch that adds real fascination, accommodating a celestial chart, horizon (engraved in yellow and indicating the night sky at a location of choice), geographical coordinates, solar time, sidereal time, sunrise and sunset display as well as a display showing daytime, night-time and twilight (indicated via a polarisation filter that makes the background appear grey by day and blue by night). Additionally, there is a completely integrated perpetual calendar behind the display.


Each astronomical chart is totally unique and the amount of stars printed on to the sapphire obviously differs depending on whether the owner lives in the northern or southern hemisphere. The man responsible for mapping the charts, Professor Ben Moore, Director of the Institute for Theoretical Physics at the University of Zurich (a position once held by Einstein), became involved in the project just over a year ago and says: "I initially came to Schaffhausen wearing my Swatch watch. I knew very little about watches at that point but I'm now very proud to be a part of IWC and this project."


movementThe new in-house Calibre 94900.


Describing his part in the process, Moore says: "The people at IWC give me the co-ordinates and, after running them through a computer programme that I have written, I return a vector diagram of dots and lines that indicated the position of about 2,000 of the billions of stars in the universe. Although the watch wouldn't be any real use for a practical astronomer - we need to be precise to within a millionth of a second in order to point the telescope accurately - it does give a very good idea of sidereal time. It's interesting and it's fun and to have a gadget this sophisticated inside a watchcase is unbelievably impressive. The Sidérale Scafusia is accurate to 11.5 seconds per year and this is a huge achievement."


Ten years in the making

By any stretch of the imagination, a 10-year project is a massive undertaking. Contributors to the Sidérale Scafusia have come and gone (including the genius designer and developer Jean-François Mojon) but despite all the headaches - especially with the constant force tourbillon - the project was never questioned. The product would not be taken to market if there was a chance that something could go wrong, and huge investments were made to prevent the plug being pulled.


The obvious question about the length of, and investment in, the project is why IWC felt the need to build anything so complicated. The answer according to Pantli, is simple. "IWC has made great efforts in recent years to globalise the brand and people were commenting that it was becoming a marketing brand rather than a horological one. We had to prove everyone wrong, but every manufacturer has a tourbillon these days so we had to make our's special. We did this by adding another complication."




When asked whether the advancements may trickle down to other IWC products, Pantli smiles. "We don't exclude that as an option. Maybe not in the next five years but it is a distinct possibility we will use these skills to create another project." "It would be wrong to try and do it at this time," adds Karoline Huber, Director of Marketing, "but all of the engineers that worked on the Sidérale Scafusia are highly skilled and we have to keep giving them interesting projects or they will start looking elsewhere. So maybe down the line…"


The piece costs a flat SFr.750,000 and takes a full year to create, during which time a customer is kept up-to-date with the progress of the watch and has a 24-hour hotline to Pantli himself.  The watch couldn't be further from a series production piece, with customers basically getting to put together their own watch consisting of individual astronomical chart - including personalised star chart and horizon as well as sunrise and sunset times requiring mechanical parts to be custom-manufactured - as well as over 200 possible combinations of base metal, dial colour and strap design.


"This is extremely important," says Pantli. "When someone is prepared to spend that much money on a watch they should have a personal involvement. He is not buying an IWC watch but a watch created for him by IWC. If he wanted the case in titanium or steel instead of a precious metal or to have the tourbillon hidden, we would do this because it is in line with IWC. There are limits though - absolutely no diamonds!" 


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