Ressence is a company whose entire design vision is based fundamentally on a single idea. Ordinarily that’s not a good thing for a company that wants to be in the game for the long term, but in the case of Ressence, at least so far, that single idea has proven to be a very fruitful one. Part of the reason for this is that it’s a very good idea. Another reason is that in order to make the idea work, quite a lot of original research and development had to be done, and the results are watches that are not only aesthetically unlike anything else any other company makes, but also very mechanically ingenious as well. Yes, they’re expensive, but there are reasons: the unique design, and just how much it took to get there.
The first time you pick up a Ressence watch can be a very disorienting experience. A reaction I’ve seen from several people who weren’t already familiar with the company was that this must be some sort of electronic device with an extremely high pixel density display, which of course is not the case. It’s an understandable reaction, though. In the Type 3-3, the indicators for the minutes (the largest central hand) hours, day of the week, date, function indicator (which turns once every 6 minutes/360 seconds) and “oil temperature gauge” (which we will get to in a minute) seem to somehow be a part of the surface of the sapphire crystal. Despite the illusion, however, Ressence watches are mechanical – in fact, the base caliber is an ETA 2824. The display consists, not of hands, but of a series of smaller disks set into, and on the same plane as the surface of, a single larger disk. That larger disk rotates once per hour (driven off the cannon pinion of the base caliber) and as it does, additional satellite gearing makes the smaller disks turn at varying speeds as well, to show with hours.
In the case of the 3-3 (which is the latest variation on the Ressence model 3 that originally launched at Baselworld 2013) the date is shown, as well as the day of the week. The interior of the watch is divided into two completely physically separated chambers. The lower contains the actual movement, and the upper contains the gearing for the display disks. The upper disk is also filled with oil (about 35 milliliters), which is what creates the illusion that the hands are on the surface of the crystal.
So how does the visual illusion actually work? The oil used has a refractive index essentially identical to that of transparent sapphire. Refractive index sounds pretty technical but it’s really pretty simple; it’s a number that says how much faster light travels in a vacuum than in a given material (for instance, the refractive index of pure water is 1.33, which means light travels 1.33 times faster in a vacuum than in water).
There’s a well known science party trick often used to illustrate what refractive index means, and it involves dipping a glass rod into a beaker full of vegetable oil. As it happens, the oil and the glass have a nearly identical refractive index and the result is that the glass seems, rather weirdly, to simply disappear.
And that’s really all there is to it. Now, the basic physics and optics are pretty simple (those of you who’ve done life sciences lab work might be reminded of oil immersion lenses in microscopy, which exploits the same principle) but making a working watch based on this principle is definitely not so simple. You need the chamber housing the main disk and its satellites to be completely filled with oil, and this presents two problems. The first is that a watch movement won’t run if it’s immersed in oil – it’s not so much the gears and pinions that are the problem, but rather, the escapement and balance. Oil is pretty viscous stuff and the lever wouldn’t be able to lock or unlock, the escape wheel wouldn’t be able to jump forward with each tick of the balance – and of course, none of that would matter because the balance wouldn’t be able to turn. This is why the upper chamber has to be sealed off from the lower – but if the upper chamber is totally sealed, how does the movement in the lower drive it, and how do you set the time?
The other problem is that for the effect to really work, the oil chamber needs to be completely full – no bubbles – and the volume the oil displaces changes with temperature. That means some way has to be found to allow the volume of the upper chamber to vary so you don’t spring any leaks. Both problems had to be solved in order for the great idea to actually work.
Each of the two chambers is mostly made up of a curved sapphire crystal. The lugs of the watch are continuous with the case middle, which separates the two thanks to a thin titanium membrane, like a drumhead (the case band and lugs are titanium as well). The only possible means of interaction with the movement is through turning the sapphire crystal that forms the back of the watch. This can rotate, and in doing so it can turn the main disk (and thus the satellites as well), allowing you to set the time and date, and wind the movement. The whole design is called the ROCS (Ressence Orbital Convex System).
The upper and lower chambers are completely physically isolated from each other, so how can turning the case back change the position of the satellites in the upper chamber? The answer is a tiny disk in the center of the lower chamber, and on the central axis of the movement, that has minute, very powerful magnets mounted to it. These exert an attractive force on a corresponding plate, located in the upper chamber. The lack of a direct mechanical link means you shouldn’t turn the lower caseback sapphire too abruptly as you might decouple the upper and lower magnetic disks, but in my experience with the system (over a week plus of on and off wear), that never happened once, so it seems very secure and reliable, all things considered. When the watch is running, the lower magnetic disk turns once per hour, and this of course turns the upper main disk once per hour as well.
The magnets are very powerful, which could upset the rate of the movement. However, they’re enclosed inside a ring of material that has a very high magnetic permeability – this is the same principle you find in watches that use soft iron dials and cases; the material provides a preferred pathway for magnetic field lines.
The only other downside to this system is that there is no quickset for the date, and if the date is significantly off, setting it can be, as one says in the vernacular, a royal pain in the ass. Our 3-3 was 15 days off, which meant turning the case back a lot. It takes several turns of the case back crystal to advance the time by one hour, and if you have 15 days times 24 hours to go through, you’re going to be there a while. I actually had to twist the case back over 1,000 times to set the date, day of the week, and correct time. It’s far from a deal-breaker as the watch overall is visually spectacular, but if you’re considering buying one, I strongly recommend either a winder or a domestic servant with no other duties and very strong fingers. (Actually one solution I discovered is the use of one of those soft rubber balls watchmakers use to remove screw-off case backs; we have several in the office and they make rotating the sapphire back much easier. Update: Ressence also provides a complimentary Kubik watch winder with each Type 3.)
The other problem is the change in oil volume with temperature. The solution here is as ingenious as the magnet system. The titanium membrane between the two chambers sits on a semicircular disk that holds an arrangement of minute bellows. A valve system allows oil from the upper chamber to alternately fill or empty the chamber in which each bellows sits, as the volume of oil rises and falls with temperature changes.
It’s a simple and ingenious solution to the problem; and, there is a small thermometer built into the main satellite disk, which you can see below – it shows you the safe operating range in white, and the danger zones for high and low temperature in red and blue. The thermometer works off a bimetallic metal spring that lengthens or shortens with temp changes. An interesting note on assembly is that the watches are assembled at the minimum operating temperature – five below zero, Celsius – so that the oil in the upper chamber has plenty of room to expand as things get warmer; the total temperature range is -5 to +55 Celsius (23 to 131 Fahrenheit).
The day of the week indicator is the seven-segmented dial at 6:00 in the image, and the function indicator is just about at 12:00.
That’s the basic setup, but the effect is very much more than the sum of the parts (and they’re pretty impressive parts). One of the nicest payoffs to the design of the Ressence 3 is that the indicator satellite disks are very generously treated with SuperLuminova and the result is one of the finest after-dark light shows I think I’ve ever seen.
As we implied in the title (and we admit, we were being a bit deliberately provocative), on paper, this might seem a very weird value proposition indeed. At a price of $42,200 dollars, there are a tremendous number of options that offer much-easier-to-understand upside than you get from Ressence. But I think that to focus just on numbers is missing the boat a bit. The Ressence 3-3 is like nothing else out there, and moreover it’s like nothing else out there by a considerable margin. “Is it worth it?” isn’t really as apropos a question as, “Do I love this design?” The visual impact of the 3-3, and how it goes about creating that visual impact, put it in some pretty rarefied company – for sheer ingenuity at the service of mesmerizing design, I don’t think it has a whole lot of competition (it puts me in mind of some of the more sophisticated Cartier mystery clocks, for instance, which are some of the few fool-the-eye horological complications I can think of that are in the same league as the 3-3).
Christopher Walken once said, famously, “I’ve been very lucky in my career, in that, in Hollywood, if you want a Christopher Walken type, you pretty much have to hire Christopher Walken.” The Ressence Type 3-3 is like that. Its appeal is very specific, but if it really hits the sweet spot for you in terms of design intelligence and aesthetic impact – well, it’s pretty much the only game in town.
The Ressence Type 3-3: Hours, minutes, runner/function indicator (360 seconds) day of the week, date, and oil temperature indication. Movement, ROCS 3, bellows system to compensate for temperature changes in the oil reservoir, magnetic coupling and shielding system. Base caliber ETA 2824/2, self-winding, 36-hour power reserve, 28,800 vph. Grade-5 titanium dial with four satellites, engraved indications filled with (a lot) of Superluminova. Case also Grade-5 titanium, with two sealed chambers, domed sapphire crystals top and bottom. 3 atmospheres/30 meters water resistance, 44 mm x 15 mm; very light on the wrist thanks to the titanium case middle and general construction. More at ressencewatches.com.
Check out Ben Clymer’s take on the Ressence Type 5 dive watch right here – yes, a Ressence dive watch.
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