On Monday and Tuesday of this week, Cartier invited around 100 of the world’s top watch writers and journalists to their La Chaux de Fonds factory, where they unveiled their second concept watch, the ID Two. Due to an oversight at Cartier, I was also invited. Here is my report.
What is a “Concept Watch”? In simple terms it is a watch which explores new technologies but is not intended ever to be manufactured for sale. This, of course, raises the question of why a publicly traded firm, would spend copious amounts of time and money (I guess somewhere between 1 and 5 million Swiss France) on a watch that will never be sold.
In reality there are a couple of good reasons to do this; firstly, if you have a highly qualified research team, you not only want to keep them occupied, you want them to feel free to explore ideas ‘outside the box’ (as the saying goes). Secondly, until you build the concept watch, you don’t really know which of these new technologies MIGHT work in the real world. The automobile industry has made concept cars for decades; and, whilst the vast majority of concept cars are seen only at Motor Shows, a few do make it to the production line and many more of the ideas seen in these cars are in everyday use now.
I have used the word ‘Idea’ a lot in the previous paragraph, it is not a co-incidence that the name ‘ID’ is pronounced in French as ‘idée’, which happens to be the word ‘Idea’ in French.
The ID One, introduced three years ago proposed the idea of a watch which needed neither lubrication nor adjustment over the life of the watch; the ID Two examined the idea of a watch which would be much more efficient than any current watch. I was unaware that current mechanical watches are only 25% efficient; in other words, they waste 75% of the energy that is given to them. OK, now let’s be honest, in all my (almost 30) years in the watch business, I have never heard anyone complain that they wished that their watch was easier to wind and that they didn’t have to strain themselves winding their watch.
But there are major advantages in timekeeping and in watchmaking if the energy losses can be reduced, so the folks at Cartier set themselves three challenges:
• Challenge 1: Store the maximum energy
• Challenge 2: Maximize the energy transmitted from the barrels to the oscillator.
• Challenge 3: Minimize consumption of the oscillator.
Instead of the normal steel mainspring found in almost all other watches, the ID Two uses springs made of fibreglass; which, if you have ever seen a pole vaulter in action, you know can store energy very well. But it isn’t just any fibreglass, they make sure that the fibers are all aligned in one direction, these fibers are only 17 microns thick and bound together with epoxy resin, and then polymer coated for decreased friction between the leaves of the spring, this coating is applied at low temperature so as not to damage the flexibility. What is unusual about these springs is how thick they are compared to a steel spring, this is intentional, as the torque of a spring increases by the cube of the thickness. So a slight increase in thickness can give a large increase in torque, thick steel springs are not feasible because there would be much more stickiness between the leaves of the spring, which would tend to cancel out the gain in torque.
There are actually four barrels, in two vertical pairs, each in series and the inside of each barrel is coated in ADLC (Amorphous Diamond Like Carbon) which has an extremely low co-efficient of friction, meaning that there is almost no slippage of the mainsprings catching on the inside of the barrels. These new barrels and springs provide an increase of 30% in useable energy over conventional metal springs and barrels. The added benefit is that due to the almost total lack of friction these new springs produce an almost constant force output, which means that when they reach production there will be no problem adding complications such as perpetual calendars which are notoriously power hungry.
Conventional watches use a series of wheels & gears to transmit the power from the mainspring(s) to the escapement. These are normally large wheels turning small geared shafts which in turn drive other wheels and shafts, increasing the rotation speed by 2,000 to 1. But all the way down the train, energy is lost due to friction between the teeth of the gears but also by the dragging of the pivot points on their bearings. If some of these intermediate gears could be reduced, considerable energy savings could be made, and this is what has been done by Cartier. The linear reduction gearing has been replaced by a planetary system as used in such different items as automatic gear boxes, jet engines and pencil sharpeners; the Wikipedia entry states, “The planetary gearbox arrangement is an engineering design that offers many advantages over traditional gearbox arrangements. One advantage is its unique combination of both compactness and outstanding power transmission efficiencies. A typical efficiency loss in a planetary gearbox arrangement is only 3% per stage. This type of efficiency ensures that a high proportion of the energy being input is transmitted through the gearbox, rather than being wasted on mechanical losses inside the gearbox.”
But there are even more energy savings to be made in the gearing, the conventional profiles on the teeth have been replaced by specially designed contours. Extraordinarily smooth ADLC-coated pivots at the tips of the gears’ staffs reduce friction in the ruby bearings by one-fourth, and they accomplish this reduction without lubrication.
Another innovation lies in the novel materials used for the wheels. Traditional brass and steel have been replaced by carbon crystal-coated silicon. 60% harder and 70% lighter in weight than steel, it’s also non-magnetic and resistant to corrosion, as well as having extremely smooth surfaces.
These parts reduce friction to one-fifth of the friction generated by the confrontation between steel and brass. Less friction goes hand in hand with minimized energy consumption and nearly no signs of wear. All in all, there is an energy saving of 10% over conventional gear trains.
The next part to be examined was the balance and escapement; the balance wheel is one of the main users of energy in a watch, along with driving the hands, so it is one of the places where the most savings can be made.
The escapement is one of the most fundamental parts of the mechanical movement; its role being time measurement. With no exceptions, all escapements perform two almost contrary tasks. On the one hand, they prevent the gear train from wildly escaping, i.e. racing ahead unrestrainedly and quickly exhausting its available energy reserves. On the other hand, they keep the balance and its balance-spring in oscillation by providing them with impetuses at regular intervals. The three phases in the swinging of the balance are important for proper functioning of an escapement. They are:
• the impulse
• the forward turn, and
• the backward turn.
During the first phase, the balance receives an impulse from the gear train via the escapement. The balance consumes this tiny quantum of energy throughout the remainder of the arc until it reaches the point where its motion reverses. The backward turn commences and continues until a new impulse propels the balance into its next forward turn.
To achieve this, the escapement consumes quite a large amount of energy. The escapement mechanism alone devours two-thirds of the conveyable power, leaving only a modest one-third of the total energy allowance for the impulses that keep the balance oscillating.
One of the reasons for such high energy consumption is the limited manufacturing precision of traditional materials. This limit in precision causes gear play between the anchor and the anchor wheel.
Using the deep-reactive ion etching (DRIE) methodology, the Cartier ID Two concept watch anchor and anchor wheel are manufactured in carbon crystal for a perfect fit. Essentially, the carbon crystal is grown and then plasma etched, with perfect edges reducing friction to almost zero, by having this perfect finish on the edges it meant that there was no need for lubrication.
All pivots & jewels are coated with ADLC to massively reduce friction and to operate without the ‘benefits’ of lubrication.
If you remove the balance complete from a watch & start it rotating by hand, it slows down and stops quite soon, and the question they asked at Cartier was ‘Why?’ On detailed examination it was found that 20% of the energy loss in a balance is caused by friction at the pivot points but 80% was lost to aerodynamic forces. As the balance wheel rotates, it has to push the air out of its way; so the decision was made to try to reduce the air resistance. Initially they smoothed the edges of the balance wheel and hairspring, but this had little effect; so a decision was made to do something radical; to run the watch in a vacuum.
Interestingly, there had been knowledge of these aerodynamic losses for over 70 years, as Rolex introduced the Superbalance in the 1930s where the timing weights were recessed into the surface of the wheel, thereby reducing the aerodynamic turbulence. In the 1950s, Patek Philippe did a similar thing with their Gyromax balance wheel.
By removing the air inside the watch, some problems arise; at extremely low pressure liquids boils instantaneously, so all oils and lubricants had to be removed. However Cartier was in the fortunate position of having developed the ID One, three years previously which was lubrication free. So, the technologies used in that watch were now applied to the new one. The benefits are no dust or pollution can enter and the movement is unaffected by humidity, also with no air to impede the balance wheel, it now has an amplitude gain of around 25%
By sealing the movement in an airtight case, it meant that there was no way to adjust the timing of the balance, so an adjustment free balance and hairspring had to be developed. The wheel is also made from Carbon Crystal, which means it can be made to tolerances of less than one micron, so it is perfectly in balance right from the start. It is then coupled with a Zerodur balance spring, Zerodur is a lithium alumina-silicate glass-ceramic material used in deep space telescope lenses, as zero expansion is critical in retaining focus. Paired together, they provide an adjustment free balance with minimal mass, lower mass means lower energy requirements. The skeletonised plates are made from titanium which is then coated in ADLC. As Sir Colin Chapman once said, “Simplify, then add lightness” and that is what they have done here throughout the watch.
But the big question was “How do you make a case completely airtight, capable of holding a vacuum for a decade?” If you think of all the problems of making a watch case watertight, how do you go about making one impervious to molecules much smaller than those of water? The first thing to think about is reducing the number of joins, as anywhere where case parts come together there is likely to be a gap, or the potential for one. The norm is for a case to be made from four parts; case centre, case back, bezel and glass; all of these interface with each other with a gasket between them. In effect, all of these contact surfaces are doubled; there is a contact between the case back & the gasket and between the case centre and the gasket, meaning that there could be as many as six points of contact, to say nothing of the winding crown, which poses its own problems.
To solve this problem, Cartier and its suppliers did something no one has ever tried; they made a true monobloc case; where the centre, lugs, bezel and glass are all one item, meaning that there needs to be one other part, the case back. Obviously, if the case is to be made in one piece, then it needs to be transparent, but glass is too fragile and sapphire can only be made in certain shapes, so a wholly new idea was sought.
The case is made from a new material called Ceramyst, which is a ceramic but yet completely transparent, and (unlike sapphire or acrylic) it is UV resistant, meaning that it can protect the dial from fading.
The case was made by the ceramics division of St. Gobain, a French company and one of the world’s largest glass makers. The ceramic composite division was recently taken over by the US company CoorsTek, one of the most advanced composite firms in the world. Based in Golden, Colorado a glance at their name will tell you where their money came from.
The case is moulded from powder & liquid, placed in a mould and then placed under high pressure and temperature. The ‘raw’ case comes out opaque and then polished in vibrating drums of different materials, starting with metal chips and going down in abrasive qualities to chips from coconut shells. The mating surfaces of the case & case back are machined flat to very high tolerances, which enables the very precise fit needed to hold the vacuum.
However, the watch still needs gaskets to seal the gaps between the case back & the case centre and also on the winding stem. These are very special gaskets, as they are sealed by being ‘doped’ with nanoparticles, which seal all the microscopic gaps, both on the surface and internally, meaning that there is no way for air to enter the case. Because there is a vacuum inside the case and normal atmospheric pressure outside the case, the case back is essentially ‘sucked’ onto the case. There are no screw threads or anything actually holding the two parts together other than air pressure. The watch is reckoned to remain impermeable for a decade, even with the winding crown being pulled and rotated in normal use.
The net result of all these efforts is that the watch produces 30% more power and consumes half as much energy as a traditional watch and in a conventionally sized case the movement has a 32 day power reserve.
With the ID Two, Cartier opens the way for fundamental changes for watchmaking: higher efficiency means many improvements, such as miniaturisation, increased autonomy without increasing the volume, durability, more complications and of course improved chronometry.
In my opinion, Cartier has opened a new chapter in the history of mechanical watchmaking.
St. Gobain/CoorsTek were not the only outside supplier used; companies from the dental, glass and micro-electronics industries also were involved. But, to me, the most interesting fact revealed was that NO watchmaking research or manufacturing firms were involved. This was an attempt to develop a watch from a completely blank sheet of paper with no existing assumptions. In my opening, I asked what is the point of a concept watch; well the answer is that much of the technology in the ID One watch will be available in the new the Rotonde de Cartier Astrotourbillon carbon crystal, due to be launched next year. So, I predict that much of the technology seen in the ID Two will be at an SIHH salon before long.
In closing, I would like to thank Thierry Lamouroux, Edouard Mignon & Astrid de Montlivault of Cartier for their courtesy and their endless patience under my relentless questioning.