In 1953, the first dive watches featuring a rotating bezel appeared. They started with a depth rating of about 100 meters. It took another 10 years for makers of serially produced dive watches to reach the symbolic 1,000-meters mark. And, as we at Diveintowatches.com have discovered, achieving this milestone might have been considerably less difficult than proving it.
Around 1963, a new dive watch from Sandoz with a cushion case (sometimes referred to as the “baby Panerai” by collectors) debuted, along with the Caribbean watch from Jenny, most likely the first 700-meter-water-resistant watch, which featured a monobloc case. Both of these types would become available later, under many different brands, in the years to come, and these therefore can also be considered two very early examples of private-label production for this type of watch. More importantly, during the 1964 Basel watch fair, both watch models were already described by the press as a new generation of dive watches, capable of withstanding up to 100 atmospheres (1,000 meters of water resistance). This one-year gap in communicating the actual depth ratings could very well be an indicator that building such watches might have been difficult, but finding the right testing equipment to prove it was even more difficult.
This was a problem that actually did not change much over the next 50 years: the Rolex Sea-Dweller Deepsea (introduced in 2008), for example, offers a water resistance of 3,900 meters and the pressure-testing equipment required the expertise of the deep-sea diving technology experts at Comex. On the other hand, Hublot, which launched the Hublot Oceanographic 4000 in 2011, has a dedicated Roxer tank to test water-resistance at its manufacture in Nyon, Switzerland. Charmex chose a different solution for its CX Swiss Military “20,000 Feet” dive watch introduced in 2009. The company cooperated with the Oceanographic Institute of Southampton to test its record-breaking chronograph up to 7,500 meters. Meanwhile, the German brand Sinn decided to invest in its own equipment capable of generating a pressure equivalent to 12,000 meters.
Probably the most practical approach to test a watch’s water-resistance was chosen by Rolex, beginning in 1953, for its legendary Rolex “Deepsea Special.” That watch’s prototype reached a depth of 3,150 meters that year and, in 1960, the watch was successfully submerged to a depth of nearly 11,000 meters during Piccard’s and Walsh’s famous “Deepsea Challenge” dive. In other words: Rolex used the whole ocean was used as its testing environment.