The waterproofness of watches

"The tightness of the cases was undoubtedly the most revolutionary discovery"  

When you ask watchmakers what horological invention revolutionized the 20th century, they often react with bewilderment and end up saying: quartz. Nevertheless, the tightness of the boxes was undoubtedly the most revolutionary discovery that allowed houses and master watchmakers to free themselves from certain constraints and to invent, incidentally, some of the most famous watches in the history of wristwatches. In addition to allowing them to be used in all circumstances, sealing has clearly contributed to improving their resistance and lifespan. This primordial innovation has contributed to changing the course of time...

The history of watch water resistance:


We know that until the beginning of the 20th century, the idea of ​​protecting a watch from the attacks of water in liquid form or suspended in the air in gaseous form was not the priority of watchmakers, if not manufacturers of marine chronometers deploring that their instruments on board ocean-going vessels are exposed to salt erosion.

Historically, water resistance became essential when timepieces moved from the pocket to the wrist during the First World War. Unsuitable for all-terrain use, they suffered the outrage of water and dust that seeped into the heart of the mechanisms. However, a British watchmaker named John Harwood, a soldier in the Great War during the Battle of the Somme, measured how much, under the deluge of iron and steel, owning a watch that was reliable in all situations and waterproof could be prove decisive.

Demobilized, this skilful designer, convinced of the vital nature of his mission, filed a patent in 1923 for a self-winding watch capable, thanks to a construction dispensing with a winding stem passing through the case, of resisting the intrusion of dust and, by incidence, to splashing water. A mechanism allowing winding through the movements of the wearer should contribute to limiting manipulations liable to cause the infiltration of water or harmful particles into the confined enclosure of the movement.

Around the same time, Hans Wilsdorf, founder of the Rolex Manufacture, was thinking about technical solutions to increase the resistance of watches used by soldiers or often British expatriates - based in colonies located in humid tropical regions, subequatorial or countries experiencing the devastating monsoon rains – at humidity levels of 95-98%. In 1926, after extensive research to find the simplest and most effective solution, he filed a patent protecting the invention of a winding crown screwed onto a tube attached to the case, the parts of which are independent of each other. others formed, after screwing on a seal installed at the bottom of the crown, a strictly watertight whole. Thanks to this astonishingly simple patented system, which bears a strong resemblance to the collars screwed on a cap nut that plumbers fit to seal a pipe, Rolex was thirty years ahead of the competition in the field of authenticity.

As the manufacture already had at that time a singular tale for communication, it validated its invention and imposed it on the world by putting it on the wrist of Mercedes Gleitze, a young Englishwoman who in 1927 accomplished an individual feat by crossing the Channel at the swimming. A visionary, Hans Wilsdorf sensed that the invention of water resistance opened the way to sports watches, intended for the "stronger sex" as well as the "fair sex"...


In the 1930s, it remained to generalize its use. The Second World War and the return to peace, with the desire of young people to live enriching human adventures, was to provide the framework for this expansion through a new activity made accessible to all thanks to the invention by Cousteau and Gagnan the regulator – this one allowing a diver to do without heavy diving suits to discover the seabed.


At the same time, the competing brands, angry at having had their hair cut at the post, reacted by presenting their vision of the diver's watch. In 1932, Omega produced the "Marine", whose double rectangular case was tested in 1937 at 135 meters and returned to center stage 80 years later under reference No. 7 in the "Museum" Collection.

Then, in the 1950s, it launched the "Seamaster" collection with the success that we know due in particular to a very attractive price-quality ratio at the time. Also in the 1930s, the Mido house offered its waterproof version using a cork seal, while Cartier dared for the Pasha of Marrakech a watch with a cabochon screwed onto the crown, so that the local potentate could bathe. in the pool without having to remove it.

This type of construction (crown encapsulated under a screwed stopper) was retained by various manufactures including Zenith, Movado, Longines for military or associated uses. All the houses got into it, aware of the strategic nature of the water resistance of watches during the conduct of modern warfare. And at the end of the 1930s, they knew that they would receive orders... The armies needed for their elite troops time instruments working on all the fields of operations.

Because it was about the coordination of operations, the effect of surprise and, in many cases, victory. At the height of the Second World War, the American brand Hamilton offered moisture-resistant watches for US troops. At the same time, the Italian army, rather than relying on export watches, ordered special, waterproof watches from the Florentine company Officine Panerai to equip its combat swimmers. Classified as "Secret Defense", these time-measuring instruments discovered by the general public after the 1990s evolved to receive, in 1942, a so-called "click" system making it possible to guarantee parts up to 200 meters thanks to the compression of the crown on its joint using a lever integrated into the protective bridge.


Health through sport:


Once peace returned in the late 1940s, splash-proof and dust-proof watches became essential, as they represented the first step in a global reflection aimed at improving the functionality of horological instruments.

To meet the expectations of a generation that had to be made to forget the horrors of devastating conflicts, more and more brands produced waterproof watches that adventurers chose for their raw qualities. Thus, the Eterna model, carried on the Kon Tiki raft in 1947 by the adventurer Thor Heyerdahl when he discovered the settlement of the islands of the Pacific Ocean by Amerindian populations, inaugurated a new era in terms of resistance to the environment. outside.

Very quickly, waterproof watches won their quarters of nobility by being worn by heroes of the modern world. These instruments, hailed by young people, allowed the brands to show the extent of their technical know-how and their ability to produce extremely reliable timepieces. Naturally, watertightness and sturdiness were powerful selling points.

Manufactures such as Blancpain with the 'Fifty Fathoms', or Rolex with the 'Oyster Perpetual Submariner' have benefited since 1953 from the image of resistance and sportiness that these specimens gave off and which remain more relevant than ever, since the "Fifty Fathoms" is one of the most popular references and that Rolex presented this year at Baselworld the brand new "Oyster Perpetual Submariner Date" with a Cerachrom® bezel.

Even today, these achievements redesigned and adapted to the modern world, but overtaken by dive computers in the purely professional sector, remain essential references in the same way as the Omega "Seamaster" worn by James Bond or the iconic "Seamaster Ploprof 1,200", the specialized versions of the "Diver's 1000 meters" collection offered by Seiko, or the series of the latest extraordinary watches from Oris dedicated to the Italian soldiers of the Col Moschin commando.


Regulatory issue:

When Rolex lost its monopoly due to the fact that its patented invention fell into the public domain, all the brands obtained, de facto, the authorization to equip their creations with this screw-down crown system considered to be the safest in terms of water resistance. .

For a broader spectrum of use such as water skiing, sailing and a fortiori diving, the amateur will turn to models with crowns and screwed pushers for the chronos, whose water resistance will be at least guaranteed up to 100 meters. .

In this register, the list of possibilities is immense because almost all the brands, from the smallest to the most famous, have in their collection at least one diving watch worthy of the name. It is therefore difficult to choose between a TAG Heuer "Aquaracer 500 Chrono" with its Caliber 16, the very latest "Chrono 500" from Victorinox Swiss Army equipped with a quartz caliber, or other models, each more attractive. than the others. In this register, some will appreciate the option chosen by Jaeger-LeCoultre for the "Master Compressor" collection, to approach a gesture as natural as opening or closing a tap, in order to secure the manipulation of the crown and the pushers. . In this regard, the "Master Compressor Navy SEALs" have integrated this detail since it is part of the functionality sought.

As far as scuba diving is concerned, in addition to judicious choices such as the new "Tudor Hydronaut II" chrono, enthusiasts will equip themselves with playful timepieces such as the new TechnoMarine "Cruise Sport" 45 mm in diameter, or opt for trendier versions such as the "Tambour Louis Vuitton Diving" in the catalog of the famous leather goods manufacturer, the "Dior Numéro Rouge D02" or the superb "Chrono Clipper Automatic" from Hermès.

There are also very technically advanced pieces, such as the RM 028 by Richard Mille. Unless, for total safety in action, they favor a dedicated computer like Tissot's "Sea-Touch" or the new "Yema Sous Marine Snorkeling", these two pieces offering incredible functionalities more or less equivalent to what offer dedicated computers. More affluent amateurs will be able to rely on captivating pieces rediscovered at GTE (Geneva Time Exhibition) last January in Geneva. Various young designers rubbed shoulders there, including the founder of the Linde Werdelin brand, a company that uses a mechanical watch to which a high-performance dive computer can be attached by clipping. Okay, it will never be worth having the IWC Aquatimer Deep Two" on your wrist, which we know has a mechanical depth gauge. This reference, presented last year and recently in stores, will certainly be the ultimate weapon for anyone looking for a timepiece that only a lucky few can hope to wear.


In any case and whatever the choice, it will be good to check that your diver's watch meets the ISO 6425 standard of 1996 (NIHS 92-11 standard). Indeed, to comply with their designation of diver's watch, they must meet several conditions: water resistance equal to or greater than 100 meters, a dive time control system graduated in minutes (an internal or external rotating bezel) protected against any handling error.

On the other hand, the case, which is necessarily anti-magnetic and corrosion-resistant, must imperatively feature a dial that can be read in the dark and an operating indicator such as a second hand or a system for indicating the end of battery life (for quartz models). The best being the enemy of the worst, purists will always rely on models proven by very great depths, whose quality, again meeting a specific ISO standard, will have been validated by professionals.

In this field, the Rolex "Oyster Perpetual Sea-Dweller Deepsea", water-resistant to 3900 meters and developed with the collaboration of COMEX (a body specializing in deep-sea diving) will always delight a public that demands the best tool in its product category. If Ralf Tech watches, still known only to insiders, of course meet the famous ISO standard, purists will particularly remember watches that are water resistant up to 500 meters like the Bell & Ross BRO2, or even 1000 meters like the Porsche Design " P'6780 Diver" which, like the Eterna "Kontiki Diver", has a specific case with a waterproof casing integrated into a protective case.


Conclusion :

Let's say that water resistance represents the best security for a watch, but that foresight and attention remain essential to its preservation. In this respect, before the application of the future ISO 22810 standard which will require the manufacturer to ensure the tightness of the part sold during the warranty period, we encourage amateurs wishing to test theirs in real conditions of use. , to have it systematically checked by a licensed watchmaker, as summer approaches.