In 1960, the bathyscaphe Trieste descended 10,916 meters (35,814 feet) to the bottom of the Mariana Trench, the deepest point in the ocean. Attached to the outside of the Trieste was the Rolex Deep Sea Special, a huge prototype of a watch with a massive bubble crystal, specially designed to make the trip to the bottom of the ocean. It worked: After the dive, the Rolex Deep Sea Special was found to be in perfect working order (now, Deep Sea Special No. 3, the one that took this trip, sits in the Smithsonian’s collection).
Today, Rolex is continuing its legacy of deep-sea derring-do with the launch of the new Deepsea Challenge. It’s crafted out of what Rolex calls RLX titanium – which makes it the brand’s first all-titanium watch – and is rated to an unfathomable 11,000 meters (36,090 feet) of water resistance. There are two stories here: the water resistance and the titanium. Let’s start by getting wet.
From the Submariner (1953) to the Sea-Dweller (1967) to the Deepsea (2008) to the Deepsea Challenge (today), we’ve always known that Rolex takes water resistance pretty seriously. And really, this isn’t the first time we’ve seen the “Deepsea Challenge” name – that was back in 2012, when Rolex produced a prototype for Avatar filmmaker James Cameron for his solo dive down into the Mariana Trench. That watch was produced in just eight weeks, but it did what Cameron and Rolex wanted it to do: It survived the dive, proving Rolex had the water-resistance chops to make a watch that could handle the pressure at the literal bottom of the ocean. However, that watch was still experimental, not yet ready for mass production. Today’s Deepsea Challenge is the commercial representation of that original experiment from a decade ago.
The new Rolex Deepsea Challenge measures 50mm in diameter and 23mm thick (of that, 9.5mm is the sapphire crystal). Rolex tests the Deepsea Challenge to 125 percent of the actual water resistance it’s rated for (i.e., 13,750 meters) and developed an enhanced high-pressure tank with long-time partner Comex to test this waterproofness (James is going to dive a bit deeper into the brand’s testing processes in a follow-up article). It’ll cost you $26,000.
For perspective, the current Rolex Deepsea is rated to 3,900 meters, so the Deepsea Challenge is rated to roughly triple that (and, for comparison, the Omega Ultra Deep introduced earlier this year is rated to 6,000 meters).
A few core pieces of tech allow the Deepsea Challenge to achieve a rating of 11,000 meters of water resistance. First, there’s Crown’s patented Ringlock system. As a former lawyer who once tried to apply for a patent in law school (and was promptly denied) for a friend/client who thought he’d developed a totally unique and novel process of beer fermentation (turns out we were very wrong, but the beer still tasted good), I couldn’t be satisfied until I found the Rolex Ringlock patent filing, so here it is: a 2007 Rolex filing for a “Sealed wrist watch case” – not new technology, but still worth highlighting.
Basically, the Ringlock is a stainless steel inner ring within the case on which the crystal is mounted on one side, and a titanium caseback on the other. This is designed to reduce stress on the case by diverting the pressure on the watch’s crystal to this strong inner ring (since the crystal has such a large surface area, a lot of force is exerted on it as a watch goes deeper underwater). Since the Ringlock takes the brunt of the pressure instead, the case itself can be thinner than it otherwise would be. In fact, in the patent, Rolex says that this is the exact problem they were trying to solve, writing in the patent application, “the problem which occurs when making a sealed wrist watch case which is resistant down to very great depths, typically of between 3,000 and 5,000 meters, is, in particular, its thickness.” Yeah, the Deepsea Challenge is a thick hunk of titanium, but without the Ringlock, it’d be an even thicker hunk of titanium. With the Ringlock, the Deepsea Challenge is a watch that can be feasibly worn by divers more serious than me (or, at least someone who’s got more serious wrists).
Like its ancestors – the Sea-Dweller and the Deepsea – the Deepsea Challenge also uses a helium escape valve that allows helium molecules to safely escape instead of blowing out through the watch’s weakest point (like shattering the crystal). Rolex patented the mechanism back in 1967 and it’s still serving dutifully in its more serious professional diver’s watches.
One interesting difference to note on the Rolex Deepsea Challenge: Unlike the Sea-Dweller or Deepsea, it doesn’t have a date. Unlike the Sea-Dweller, which was originally designed for divers who’d hang at the bottom of the ocean for days at a time at a SEALAB, the Deepsea Challenge is designed for short-term deep diving like Cameron’s adventure to the bottom of the Mariana Trench – no need to know the date when you’re merely testing the limits of humankind (and watchmaking) for a few hours at a time.
Okay, on to the other big news: The Deepsea Challenge is made of titanium, the Crown’s first all-titanium watch. It uses Grade 5 Titanium, an alloy that also includes aluminum and vanadium. I’m going to talk a bit more about titanium in our upcoming Weekend Edition, but perhaps the main reason for using titanium here was practical: When you’re making a watch this big, using a metal that’s lighter than steel makes it that much more wearable. Titanium is about 40 percent lighter than steel: The Deepsea Challenge weighs 251 grams; in steel it would’ve weighed more like 350 grams.
As you might already know, titanium is more difficult to machine than steel, most notably because it has something called a low modulus of elasticity, engineer-speak for the fact that it flexes and deforms somewhat easily (more easily than steel, for example). Rolex said that, while it took three years to specifically develop the Deepsea Challenge, it has been working and experimenting with titanium for much longer. Indeed, that 2007 Ringlock patent specifically mentions using titanium a number of times; the implementation of the Ringlock on the original Deepsea has long used a titanium caseback because of its flexible properties that allow it to withstand pressure at extreme depths – a classic illustration of “bend, but don’t break.”