What’s the equation for improving on perfection? If you’ve joined us before on Pioneer Chronicles, you’ll know that we don’t just produce our own movements – unlike most watch brands, we also make our own escapements and hairsprings. (It’s been said we’re ‘very rare’.)
Because these creations are so vital, we’d hate to leave the calculations to just anyone… after all, as Heinrich himself once said, ‘to make the best watches in the world, you’ve got to have the best suppliers.’
Ok, it’s not quite Nietzsche’s theory of universal expansion and contraction – but it’s close! The hairspring (that spirally thing coiling and uncoiling in the balance wheel) is quite literally at the heart of a mechanical watch movement. Finer than a human hair, the hairspring attaches to the balance wheel and controls its motion by expanding and contracting – limiting its rotation, before returning it to the start. And repeating the process in the opposite direction again and again… around 200 million times a year, in fact.
While size, shape, and mounting position make up the balance’s frequency, it’s the qualities of the hairspring’s composition that determine its performance and – along with a few other factors – the long term accuracy of a watch. And even though there have been recent developments in spring construction – composite materials and non-metal hairsprings (think silicon) – over the last few years, at H. Moser & Cie. we don’t think they cut the mustard. For instance, they don’t allow watchmakers to make adjustments, and can’t be produced by traditional watchmaking methods. Which really is the name of the game when it comes to a Moser.
Rule number one? Your material must be impervious to damage from the elements. That’s Ground Zero. And it may seem like a given, considering the various types of metal, alloy and composite used today in watchmaking – but it shouldn’t be taken for granted. Whatever material is used for the hairspring has to be resistant to oxidation and corrosion, because any change in the chemical properties of a hairspring would have a negative (unacceptable!) impact on precision.
No wobbles allowed. We’re looking for ‘invariable elasticity’ in our materials. That means no changes in response to its environment. With any metal component that has to contract and expand several times per second, elasticity and malleability are essential – to prevent what’s known as ‘metal fatigue’ over time. But when it comes to hairsprings, we have to take that basic elasticity up a notch. It can’t be affected by any changes in temperature, ambient pressure, or any sort of shock – as this would distort the material and make its performance inconsistent. Translation? Inaccurate watch!
It’s not just those geniuses beetling away at CERN’s Large Hadron Collider that have to be concerned about the effects of (epic-scale) magnetism on their watches… not to mention wormholes and rips in space-time. And it’s not only Magneto who has invisible superpowers! Magnets are all around us, often undetectable to the naked eye. From hi-fi speakers, to your tablet’s fancy folding leather cover, or even airport metal detectors – magnets are everywhere. And while smaller, weaker ones may not affect a hairspring, the larger ones most certainly do! Luckily, there are new metal alloys which have ‘paramagnetic’ properties – meaning that they are protected from magnetic fields. At H. Moser & Cie., we (along with sister-company Precision Engineering AG) have developed our very own paramagnetic hairspring with a unique combination of metals.
The Philosopher’s Stone (A.K.A. Isochronism)
Alright, this isn’t some precious jewel that can turn back time or magic water into wine. But it is a Holy Grail of sorts – the watch-word of every great watch-maker. Without dwelling too much on the physics, let’s try and explain the ins n’ outs of Isochronism (which literally translates as ‘equal-in-time’). As a watch’s mainspring barrel winds down, the torque and the amplitude of the escapement decrease. In other words? Everything slows down a bit. And while true Isochronism is more to do with the way the energy is transmitted between the ‘organs’ than their actual form, a modern hairspring still needs to have the right shape and properties to provide an isochronous performance – no matter where you’re at in the movement’s power reserve. Simply put, it must keep things balanced, coordinated, and ‘on-time’ no matter what.