Arnold & Son Constant Force Tourbillon: The Force Is Strong With This One

A not so long time ago in the minds of some very interesting people, The Force was born. It began in a galaxy far, far away . . . in Canada, with a filmmaker named Roman Kroitor. He was having a discussion with neurophysiologist and cybernetician Warren S. McCulloch when they disagreed on the true nature of life.

McCulloch had stated that, “Living beings are nothing but highly complicated machines.” To which Kroitor replied, “Many people feel that in the contemplation of nature and in communication with other living things, they become aware of some kind of force, or something, behind this apparent mask, which we see in front of us . . . .”

star-wars-the-force-unleashed

Unleashing the Force in ‘Star Wars’

From that moment on, the idea was alive. But it would not be nudged into popular culture until another filmmaker named George Lucas saw a film featuring a clip of that discussion. He grabbed the idea and developed it into a genre-defining element. It was the most powerful thing in the universe: the Force.

It saved Jedis from Wampa attacks on Hoth; it confused Stormtroopers on the lookout for a couple of suspicious droids; and it also allowed for long-distance coercion of an admiral showing a disturbing lack of faith in the Force. But the Force is not exclusive to Mr. Lucas or to Luke, Yoda, and Obi-Wan. It can be found throughout the universe and on every watch lover’s wrist with the potential energy stored in a mainspring and doled out via the escapement.

Arnold & Son Constant Force Tourbillon

Arnold & Son Constant Force Tourbillon

The Force isn’t just a Jedi mind trick

Or if you are lucky, it could be the carefully delivered force of the Arnold & Son Constant Force Tourbillon. New from Baselworld 2015, this watch features technical marvels even the engineers behind the Death Star would take notice of.

What makes the Constant Force Tourbillon so special? Well, for one just read the name again and it might give you a clue: the watch features a constant force mechanism that feeds a tourbillon with energy. What’s not made clear by the name is the fact that it does this all plus dead beat seconds powered by twin serially operating mainsprings. With a couple patents and loads of style, the Constant Force Tourbillon makes for an impressive addition to the Arnold & Son collections.

Arnold & Son Constant Force Tourbillon

Arnold & Son Constant Force Tourbillon

But why the introduction focusing on the Force? It’s because “the Force” is one of the most critical components belonging to a watch and its timekeeping ability. And it practically gets the least amount of attention. Now that has begun to change, but this watch makes it quickly clear that it is what you should be paying attention to now.

It all began with understanding what the best way to have accurate timekeeping in a watch is. The most important factor for timekeeping accuracy is consistent and repeatable amplitude and beat rate of the balance. That is achieved by ensuring that the balance is impulsed every oscillation with precisely the same amount of force. And there are many ways to do this, but many of these solutions fall short on their own. Super-long power reserves, fusée-and-chain mainsprings, as well as tourbillons and gimbaled mounts to minimalize positional and gravitational errors; but none of these on their own provide a perfect solution. The only thing that gets close is a constant force mechanism.

Arnold & Son Constant Force Tourbillon

Arnold & Son Constant Force Tourbillon

You see where this is headed

Which, of course, means the Constant Force Tourbillon has a constant force mechanism! Specifically a remontoir d’égalité (Arnold & Son has received a patent for this particular design), which comprises a small spring wound by the gear train and, by extension, the mainspring barrels. That small spring is the only physical connection between the mainsprings and the escapement as the gear train (on the escapement side) only gets its force from that spring.

This spring is rewound once every six oscillations, or once per second (do the math: the escapement runs at 3 Hz or 21,600 vph). The only change in force that could be possible would occur during those half dozen oscillations before the spring is reset. Compared to a slowly changing amount of force over many hours or days from a typical mainspring, the change in force could only happen over one second. And since the (relative) base measurement for timekeeping is the second, the change in force is negligible and can be accounted for during adjustment.

View through the display back of the Arnold & Son Constant Force Tourbillon

View through the display back of the Arnold & Son Constant Force Tourbillon

But what is more interesting than that is the constant force mechanism powers a tourbillon, which historically was a mechanism used to average out the effects of gravity on an escapement. Not necessarily needed in a wristwatch (which does not hang like the pocket watch for which the tourbillon was invented), it still is an impressive feat to have a one-second constant force mechanism directly preceding a tourbillon. And wristwatch tourbillons generally tend to be the best performers at the biennial International Chronometry Competition.

Oh, and did I mention that this Arnold & Son tourbillon features a decidedly different balance wheel compared to all of the brand’s other models? The balance is symmetrical with two wing-shaped balance sections (which could be called a balance “felly” as we learned in The Bovet Amadeo Fleurier BraveHeart: Two Brave Hearts Are Better Than One) that do not make up a fully rounded balance wheel but instead form a very non-classic balance. The fact seems to have gone unmentioned anywhere in the press release yet stood out to me as an additional artistic (and possibly engineering) departure for this watch.

Arnold & Son Constant Force Tourbillon

Arnold & Son Constant Force Tourbillon

That one-second constant force mechanism also happens to provide double duty in offering dead beat seconds, which follows in sync with the one-minute tourbillon beside it, making for a lot of engineering going on in a very small space. Dead beat, or true beat, seconds has the constant force mechanism to thank for its placement as it piggybacks right on top of it. In reality, a one-second remontoir d’égalité and a true beat seconds mechanism are very similar in operation, though very different in intended purpose.

Where does the force originate?

Before all of these mechanisms can come into play and attempt to make a very consistent timepiece, there still needs to be a large store of energy somewhere. For this Arnold & Son went with an old favorite, twin mainsprings connected in series with one mainspring running the gear train and the second mainspring continuously keeping the first mainspring wound for twice as long. This way, there is not a very large spike of power at the beginning thanks to parallel mainsprings, but instead a very long consistent level of power that allows for a smooth and even distribution of power over the course of its 90-hour power reserve.

Close up and personal with the constant force mechanism (left) and tourbillon (right) of the Arnold & Son Constant Force Tourbillon

Close up and personal with the constant force mechanism (left) and tourbillon (right) of the Arnold & Son Constant Force Tourbillon

And like a very few select others, this watch also is able to keep the escapement from running poorly and the watch from changing its rate. Thanks to the remontoir d’égalité, the mainsprings will unwind until they do not have enough power to recharge the constant force spring, at which point the escapement will not receive any more force from the remontoir d’égalité spring. Thus, the watch stops completely instead of running inconsistently. A few other watches have mechanisms called “stop works” that stop the watch when the mainspring(s) unwind to a certain pre-determined point to reduce the possibility for rate error.

Girard-Perregaux Constant Escapement

Girard-Perregaux Constant Escapement

And, of course, there is the Girard-Perregaux Constant Escapement, which threw out the playbook and made its own rules for escapement force (see 7 Reasons The Girard-Perregaux Constant Escapement Is Fit For Starfleet). So the Arnold & Son Constant Force Tourbillon is definitely in good company.

And what the Constant Force Tourbillon also has going for it is the incredible symmetrical (and modern) design matched very carefully with old-world class. This is probably what has made Arnold & Son so popular in the brand’s short rebooted life so far. Arnold & Son makes watches that can speak to almost anybody so everybody can find something they like about a model or two . . . or twenty.

But speaking for myself: I dig it. I’ve liked pretty much everything I’ve seen from this brand and am always excited to see what new combinations it comes up with.

Arnold & Son Constant Force Tourbillon

Arnold & Son Constant Force Tourbillon

If the Constant Force Tourbillon and the TBTE True Beat Tourbillon are any indication, Arnold & Son isn’t going to slow down any time soon. So while I drool over this new watch and the others, I’ll keep my eyes open and make sure I have some place to sit down when the next release comes because it might make me dizzy from its increditasticness!

So let’s break it down!

• Wowza Factor * 9.1 Like almost every Arnold & Son piece, it is impossible for the Wowza to be less than a 9, they are all so awesomazing!

• Late Night Lust Appeal * 82.22 g’s » 806.302m/s2 Heavy lust appeal to keep you up all night. More than enough to make your wife or partner ask why you never came to bed! Oops.

• M.G.R. * 67.39 With a constant force mechanism, true beat seconds, tourbillon, and architecture to inspire, this movement stands up against some great movements out there!

• Added-Functionitis * Mild . . . sort of. This is a tough one since the only added function is still not technically an added function, just a more complicated way to display seconds. Technicality aside, this movement is packed with added functions, but you would still technically only need children’s strength Gotta-HAVE-That cream for the deceptively subtle swelling.

• Ouch Outline * 10.65 – Hands full of blisters from a day of yard work! It’s a side effect all homeowners probably know, and all teenagers learn the hard way. And yet I would work my hands raw to get this watch on my wrist!

• Mermaid Moment * Oh, snap. . . literally! When you realize not only that the second hand is a true beat but attached to a remontoir d’égalité you will be on the phone with the caterer before you can say constant force!

• Awesome Total * 930 Multiply the number of pieces in the limited edition (28) with the water resistance (30 m) and add to that the power reserve (90 hours) and you land on one seriously epic total!

For more information, please visit www.arnoldandson.com.

Quick Facts
Case: 46 mm red gold
Movement: manually wound Caliber A&S5119
Functions: hours, minutes, true beat (dead beat) seconds
Limitation: 28 pieces
Price: $197,500

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Trackbacks & Pingbacks

  1. […] Arnold & Son presented its own take on the wandering hours display at Baselworld 2015 with quite a twist. Yet, with all the other impressive releases the brand came out with at the same time, like the Constant Force Tourbillon, the Golden Wheel went relatively unnoticed (see Arnold & Son Constant Force Tourbillon: The Force Is Strong With This One). […]

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