TimepieceReview

Eterna's Revolutionary Innovations

Floating atop an ocean of horological hyperbole are a handful of brands who can lay claim to having made genuine advancements to the art of watchmaking. Eterna is most certainly among them and has emphatically reasserted its position at this year’s Baselworld, as TimepieceReview had the good fortune to discover.

Eterna began producing movement blanks in 1856 and in 1876 produced its first watch. An early indication of the brand’s aptitude for innovation came in 1914, when it unveiled the world’s first alarm wristwatch at the Swiss National Exhibition. But it is 1948, a year marked by the release of the Eterna-matic, that remains the most important date in the brand’s history. The Eterna-matic, developed with the assistance of MPS (Micro Precision Systems), featured a low-friction ball bearing mounted rotor system to assist in the automatic winding; and the system has remained almost indispensable to self-winding timepieces ever since. The five balls that cushioned the rotor have subsequently been stylized to form the brand’s current logo, now proudly displayed on the dial and crown of all the pieces in the men’s collection.

Another great legacy of the brand is the story of the subsidiary company it founded in the 1930’s to produce its movements. This was of course ETA. Today, Swatch-owned ETA is the indisputable industry powerhouse and its movements are so ubiquitous that the company recently found itself embroiled in a two-year inquiry into monopoly allegations.

Eterna Today

Eterna is now owned by Ferdinand Alexander Porsche and has as such been assigned the licence for the Porsche Design collection. The marque remains based in Grenchen (alongside Fortis and heavyweights Breitling and ETA) and remains firmly dedicated to pursuing innovation, as evidenced by the presentation of its Spherodrive technology at Baselworld 2008.

Over 60 years after the original collaboration with MPS to develop the Eterna-matic, Eterna reprised the partnership to develop a new type of ceramic ball bearing on which they could mount the mainspring barrel, its arbor, and the winding wheels; in order to minimise internal pressures within the watch, reduce friction and eliminate the need for lubrication. The fruit of the collaboration is the Eterna Calibre 3800 (a test calibre that is not found in any of the current collection models) from which descend the Calibre 3505, found in the Madison Three Hands Spherodrive (this calibre is in fact architecturally identical to the Calibre 3800, save that it is rectangular and not circular) and this year’s

offering, the double-barreled Calibre 3510 housed within the Madison 8 days. Of Spherodrive, Eterna’s technical director, Patrick Kury has said: “(it) represents a revolutionary improvement to the mechanical efficiency as well as to the longevity and reliability of the watch movement”. We met with Eterna's prototype specialist watchmaker during Baselworld to examine Spherodrive technology in detail.

The structure of Eterna Calibre 3501, found within the Madison Three Hands represents the industry-wide standard design.

The arbour is conventionally required to fulfill two functions in wristwatches: 1) rotate upon its own axis to turn the mainspring 2) act as the bearing of the mainspring barrel which rotates around it to power the gear train. Usually lubrication is applied to the ruby bearings to reduce the friction but notwithstanding this, over time, the parts begin to show wear and the stability of the mainspring barrel is lessened.

Eterna lists the drawbacks of the conventional design as being:

- Labour-intensive adjustments and settings.

- Need for lubricant.

- Mechanical wear and tear of spring barrel and arbour.

- Instability of the barrel assembly.

- Loss of power and torque.

- Cost: the barrel assembly and arbour often need replacing during servicing.

- Once the barrel bridge has been assembled and the bearing oiled, it can no longer be removed without dismantling the entire watch mechanism and cleaning it again.

Eterna’s solution to these problems is to mount the most important rotating parts (the mainspring, arbour and winding wheels) on self-lubricating and almost entirely maintenance free zirconium oxide ball bearings. The illustration below shows the Calibre 3505 found within the Madison 3 hands Spherodrive.

As the watchmaker explained to us, the principle advantages of Spherodrive technology are that no lubricating oil is required and the stability of the mainspring barrel is improved. Consequently, the mainspring barrel’s engagement with the gear train is more reliable and energy transfer is more efficient. Furthermore, the rolling motion of the ball bearings alleviates some of the internal pressures within the movement and minimises any friction or wear. Two welcome benefits from this are that servicing the watch becomes a far easier and less regular process. In fact, MPS systems have conducted simulated aging tests on the ball bearings, concluding that after 20 years of service, there was almost no indication of any wear.

The company literature does not do a very good job of explaining the exact positioning of the ball bearings within the three Spherodrive calibres. We will now attempt to elaborate on the information provided by Eterna and in doing so will use the term “ball bearing” to refer to the zirconium oxide balls and the term “ball race” to refer to the track/bearing in which the balls run.

Within the original Calibre 3800, the mainspring barrel drum is mounted unsupported on 7 ball bearings in one ball race on a collar screwed onto the bottom plate. The barrel arbour is dual mounted independently of the mainspring barrel, with 7 ball bearings in one ball race below and 7 ball bearings in one ball race above. The two crown wheels are each mounted on 10 ball bearings in a single ball race (the justification for this being that less force will be required to wind up the movement and friction will be lessened). Therefore within the Calibre 3800 there are a total of 41 zirconium oxide ball bearings and 5 ball races. The configuration within the Calibre 3505 is of course identical.

Within the Calibre 3510 of the Madison 8 days however, we have two mainspring barrels and arbours mounted using the same system, but a single ball bearing mounted crown wheel to wind them, thereby giving us a total of 52 zirconium oxide ball bearings and 7 ball races (7+7+7,7+7+7, +10).

The Madison 8 Days

Finally we looked at the highly anticipated 2010 novelty, the Madison 8 days. Its impressive 192 hour power reserve is achieved thanks to its series coupled mainspring barrels, and is the perfect accompaniment to the Spherodrive technology. The development of a high-end power reserve complication certainly seems the logical progression for a brand so committed to improving the efficiency and longevity of its components. Furthermore it’s a complication which doesn’t disrupt the elegant aesthetic of the Madison’s dial, with the power reserve indicator nestling nicely between 7 and 8. And as a counterpart to the power reserve indicator, Eterna have added a large date mechanism; it appears opposite, at 2, infringing slightly onto the cobbled central patterning that of the dial.

The aperture into the workings of the watch that featured at 6 in the Madison Three Hands with Eterna Spherodrive has now been occluded. It’s a shame the technology is no longer “on show”, but with two new complications enlivening the dial, its absence is hardly felt (NB - if the Spherodrive technology were to be made visible through the dial, there would need to be apertures at 6 and 12 respectively to display both barrels). It is a wonderful watch and the most complicated that Eterna has ever produced; but there is one glaring incongruity in an otherwise excellent design. The power reserve indicator, a curved red and white slide, visible in the picture, is incredibly burdensome to read and provides very little degree of accuracy. We hope the manufacture will address this, since a slight adjustment could make a great improvement.

An outline of the current collection:

As of April 2010, the men’s collection falls into four lines; climbing from the entry level Soleure, which has been bolstered in 2010 and now employs both ETA 7751 and Selita SW200 movements, to the KonTiki, the Vaughan and finally the flagship Madison range. The lady’s collection is limited to the elegant, but relatively unremarkable Eterna Contessa.

The complications that feature within the current collection include: chronographs, power reserves, big dates, 24 hour time and a moon phase indicator. This considered, the brand’s ethos is innovation and they are sure to focus on developing their own Spherodrive system before attempting to replicate any of the higher complications. Indeed, the versatility of the ball bearing technology has already been demonstrated in the Vaughan Collection. The collection is named in honour of Philip Vaughan - inventor of the ball bearing - and is home to the excellent Calibre 3030. The lens-shaped movement sits beneath an exquisite convex dial and is the flattest movement ever to power a big date mechanism. But more interestingly, its date discs are mounted on ball bearings - facilitating an instantaneous change of date at midnight.

As a last word, we look to the Eterna KonTiki. The classic line has sadly taken somewhat of a back seat since the development of the Vaughan and Madison manufacture calibres, but it remains the most attractive of all Eterna’s creations. Its three current incarnations are the KonTiki Date, KonTiki Four-Hands, and KonTiki Chronograph; all featuring classic “arrow” hour indices and pennants at 12, 3, 6 and 9. Its worth stretching beyond the entry level Soleure Automatic for any of the three, particularly the Four-Hands, which is truly superb.

An attractive limited edition Super KonTiki also arrives this year and is not unreasonably priced. But for KonTiki enthusiasts, who have seen the Eterna KonTiki Diver discontinued, only to re-emerge in the raiments of Porsche Design (with just a flavour of Bvlgarian

imperialism), its release may not be enough to allay fears that the collection is slowly being subsumed and rebranded. We can only hope the Super KonTiki is not intended as a swan song for this fine, fine collection.

Shae Spreafico (Mar 2010)

For more information visit www.eterna.ch

Images: Eterna, TimepieceReview

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