Back in the 60’s some of the more serious timepiece manufacturers could often be seen on small boats on the lakes of Switzerland (and even bobbing on the oceans!) with a watch firmly attached to a long piece of stout string, graduated in meters. The ‘tester’ payed out the rope to the set depth and then cautiously pulled it back in to see if the watch was still intact. It sounds bizarre, but since few humans dived to any real depths at the time many manufacturers simply didn’t bother testing their depth claims, and in fact most watches of the era didn’t state a depth rating. Rolex were one of the few exceptions to this, and back then the Submariner was a 200m watch.
Watercolour by TanyaH
By the end of the 1960’s not only were these brave souls going deeper under water, but also staying under for longer due to improvements in technology. Those who spent their professional lives under the waves began to demand a better tested product as their life depended on keeping the nasty elements of their work environment on the outside of their timepiece. To accommodate this requirement, watch companies invented laboratory testing rigs to pressurise watches to check their sealing at depth. Omega led the way with the first pressurised testing machines and other assorted equipment. Serious brands also engaged the services of real divers to test their watches in the oceans, and the first professional dive watches were born like the Omega PloProf, developed with Jacques Cousteau, and the Rolex Seadweller which was developed with COMEX.
Modern high end watches are built using CNC machinery. They have high quality materials and good engineering. This means that using the test equipment in the lab brands can prove that their models will withstand serious pressure without failing. However, these days very few brands actually get their product wet during testing, after all its not really going to be much fun sending a diver to anything over a few hundred meters due to the dangers involved and the time it would take to come back to the surface to avoid the bends.
Back in 2006, this didn’t stop Pol Palacios, the Sea-Dweller owner - who also happened to be an oil company employee - to test the depth rating of his watch with his ROV (Remotely Operated Vehicle). Pol first checked with Rolex who assured him that each Seadweller is pressurised at the factory to 130bar which equates to 1300m, so theoretically he should be safe. We all know the sayings about famous last words though...
Confident in the product, he carefully strapped his pride and joy to his work vehicle and slowly sent the pair off into the briny deep. After a very gentle descent (so as not to ‘rock the boat’ and lose the watch) the ROV reached an indicated 1200 meters. This equaled a pressure on the Rolex of 122 kilograms per square centimetre. Of course this was only half of the story. The watch had reached 1200m without issue, but now it needed to make it back to the surface in one piece...
After another gentle (but no less nail-biting) cruise the ROV breached the surface and was hauled aboard. Pol rushed over to check his watch and found that it was still ticking away on time, having kept the elements firmly at bay. Fantastic!
Testing and confirming Rolex’s claim that the Sea-Dweller was good to 1200m was a superb exercise but of course this is probably the only Seadweller that will ever visit that depth; unless one falls off the wrist of a sailor over somewhere like the Mariana trench, and even then no one will witness if there is any implosion!
The simple truth is that these days we really don’t see many Rolex Sea-Dwellers. While they were a current model they were reasonably plentiful, but since they were replaced by the new DeepSea model we have increasingly struggled to find them in the condition we want, as (as usual) collectors have been grabbing and holding onto them.