There ain’t no words for the beauty, the splendor, the marvel of my
Hair(spring), hair(spring), hair(spring), hair(spring).
Stream it, show it, long as the Swiss can develop it, my hair(spring)!
The Cowsills didn’t know back in 1969 that they weren’t simply singing about the hair on their heads in their aptly named tune “Hair,” however to my ear were also singing about the miracle of material science that is the watch’s hairspring!
The minuscule, delicate, nearly impossible-to-create hairspring/balance spring is the probably the greatest advance for current logical innovation there is, as the accurate measurement of time intervals greatly expanded research approach in nearly every order of science to date.
The hairspring had been integral to one of two leading techniques for measuring time (the other is the pendulum) for nearly 300 years until electric timekeepers had safely displaced balance springs and pendulums as the most accurate planning mechanism.
Over that time, a great variety of advances were made in hairspring innovation. In any case, those advances have never really halted, and there is as yet a vibrant exertion to create perpetually accurate and predictable hairsprings from a variety of materials. The research behind hairspring innovation is probably still the most advanced research being done in the watch industry.
The delicate hairspring has a particularly important role in keeping a watch predictable and accurate that a few companies put millions in research and advancement, leading to a slew of improvements in the last not many decades.
Today I want to break down exactly what hairsprings have been historically and what they have become.
What is a hairspring?
Let’s kick this off with the basics: what is the hairspring?
The hairspring is conventionally a flat spiral of steel that is better than a human hair. It attaches to the balance wheel and, after the balance wheel gets a drive from the escape lever, it expands (or contracts), along these lines restricting the balance wheel rotation’s prior to returning it to the start. The cycle at that point repeats the other way, regularly happening somewhere in the range of five and multiple times a second.
Its exact size, shape, and mounting position leads straightforwardly to the balance wheel’s recurrence , which, when combined with the appropriate gearing, decides a watch’s rate and accuracy.
When the hairspring was first designed, it comprised of a somewhat rough semi-spiral of steel wire that was attached to a balance wheel. The early hairspring didn’t have many spirals, making it conflicting as it expanded and contracted during rotation because of lopsided “breathing.”
These early hairsprings weren’t hardened or tempered, either, so the spring power varied greatly and would in general weaken over the long haul, also that erosion was also an issue with the unstable steel. This is the place where the first foray into fascinating materials began.
Some watchmakers, including John Arnold (1736-1799), tried different things with gold-alloy hairsprings as it was a greatly improved perceived metal during that time and could be all the more easily shaped; on top of that it was completely consumption free.
But like most metals, it also experienced fatigue over the long run, gradually weakening and presenting conflicting rates. I also have seen a couple of examples of developments featuring palladium hairsprings, likely attempted for reasons similar to gold.
Eventually the art of hardening and treating steel was presented by John Harrison (1693-1776) , greatly decreasing the impacts of metal fatigue as well as erosion over the long haul and making significantly more pliable and dependable hairsprings. This led to the advancement of significantly more predictable hairsprings as experimentation with the structure factor was added to simply attempting to get a material that even worked as a spring.
This is when technicians began adding spirals and calculating the optimal terminal bends to allow for increased isochronism and steady rates. Yet, as these became better, different issues became the dominant focal point like the impacts magnetism and temperature fluctuations would have on the now more accurate hairsprings. These impacts had already been found and a few attempts at curing them had been undertaken, however none were successful.
This led to more research and improvement. Many watchmakers, most notably Abraham-Louis Breguet (1747-1823) and the firm Arnold & Dent, explored different avenues regarding glass hairsprings as the material gave a great deal of positives over the aforementioned tempered steel.
In the in addition to segment, it was non-magnetic, consumption free, significantly less susceptible to temperature changes, had increased immaculateness (as the creation interaction of glass was a lot of cleaner than that of metal alloys), and it even had lower weakness to inertial issues (knocks and stuns) because of a lower thickness. The glass hairsprings were actually rather vigorous and appeared to be a viable alternative.
Alas, it was not meant to be as other negative issues also became apparent. First, glass is rarely really a strong, which means it can move and change over the long haul, basically leading to disintegration as a hairspring. It also was precarious to attach the closures to metal components, and it was practically impossible to adjust or alter the spring once formed.
But the nail in the casket was the rate change over the long haul. Like metals, glass can fatigue and weaken, leading to a change in rate. While steel hairsprings will have a rate that accelerates over the long run from these impacts, that of glass is even worse.
This meant that especially for use during nautical navigation the calculations would change after some time and sailors could wind up way, way off base. Steel hairsprings demonstrated less susceptible to this rate change and when combined with structures, for example, a helix spiral brought about substantially more accurate watches over any longer times of time.
Moving hairsprings toward the advanced era: Invar, Elinvar, Nivarox
For many years, no dramatic changes created because of the hairspring’s already great abilities aside from refinements in structure and some improvement in material quality.
The balance spring had come far from the original by the turn of the 20th century, and thanks to Swiss physicist Charles Édouard Guillaume (1861-1938) it was about to improve in a significant way.
Guillaume built up a nickel-iron alloy named Elinvar that was erosion resistant, almost non-magnetic, yet most importantly was nearly unaffected by temperature changes making it ideal for hairsprings as it was more stable than anything that had come before.
Elinvar – a contraction of the French words elasticité invariable (“invariable elasticity”) – was Guillaume’s development to his 1896 innovation of Invar, a similar alloy that had fairly comparable properties (and aided Guillaume win the 1920 Nobel Prize in Physics for his discoveries).
Elinvar was immediately put to use for various logical apparatuses and watch and chronometer hairsprings. By the early 1930s a surprisingly better nickel-iron alloy was created, this time by Dr. Reinhard Straumann in Waldenburg, Switzerland. The name of that alloy was Nivarox .
Nivarox–a contraction of the German words nicht variable oxydfest (“invariable non-oxidizing”) – is a fracture-resistant, self-compensating, consumption free, and antimagnetic alloy comprising of seven alloying elements.
Nivarox became the most generally utilized alloy for watch hairsprings from that point on, utilized in approximately 90% of all mechanical watches continuously 2009. The company that Straumann established proceeded to build up another alloy named Nivaflex, however this didn’t surpass the broad popularity of the original Nivarox.
But something happened between the 1930s and now that altered the fate of watchmaking and hairspring research for the second half of the 20th century: the quartz emergency .
This has nothing to do with electricity and the development of the electric clock. Electronic checks were first designed in 1840 and had gradually been created over the resulting century, while the first electric watches made their introductions in 1952, with the first commercially available watches sold in 1957.
These improvements didn’t appear to change the advancement of advanced mechanical watchmaking (probably because electric clocks and watches were still largely mechanical in nature), however when quartz watches appeared in 1969 with the introduction of the Seiko Astron the whole world shifted.
The quartz development was a significant degree more accurate and steady than any mechanical or electro-mechanical development that had gone before it.
What’s more, these became cheap as time continued, making them appealing to the average consumer.
The mechanical watch industry was shattered. It required nearly 20 years for it to resemble even a shadow of its previous self. In any case, when the rise came, a zeal for research and advancement returned, if at less companies, and mechanical advancement began to march again.
Advanced hairsprings of the advanced era: it gets really fascinating here
At first during what is known as the mechanical renaissance, brands zeroed in on complications and changing to an extravagance plan of action, which is what the 1990s was all about.
But constantly 2000 the “traditional” complications were becoming significantly more common (as common as high complications in a once nearly-terminated industry can be), and brands started to actively take a gander at making new things.
This required taking a gander at each component of a watch development and seeing where innovations had been lacking for some time. Attention went to the hairspring by and by, and here’s the place where it began to get really interesting.
Rolex made the first huge introduction in the year 2000 with its now-famous Parachrom hairspring, which is an alloy of niobium, zirconium, and oxygen (for more see The Golden Age Of Rolex Movements Part II ).
Formed in a similar way to Nivarox hairsprings, the Parachrom hairspring has surprisingly better anti-magnetic properties and a dramatic improvement in resistance to shocks.
According to Rolex, the Parachrom hairspring is multiple times more accurate when encountering stuns (I’m assuming this relates to deformation or rate consistency) over traditional hairsprings.
Also, because of its high-temperature thermal vacuum treatment after framing, the Parachrom hairspring is a striking blue tone, a shading that became popular with the following enormous hairspring improvement: silicon.
Rolex, Patek Philippe, Ulysse Nardin, and the Swatch Group all shaped a research consortium by partnering with CSEM (Swiss Center for Electronics and Microtechnology) along with its IMT (Institute of Microengineering) in Neuchâtel and the EPFL (Swiss Federal Institute of Technology) in Lausanne for the improvement of the silicon hairsprings, allowing advancement expenses to be shared.
Ulysse Nardin was the first on the scene with silicon components in watches, releasing a silicon hairspring in 2001 in the Freak. Over the course of the following decade or something like that, a large portion of the major players took action accordingly, with Patek Philippe presenting the Spiromax in 2005 (Reference 5250 Advanced Research), the Swatch Group via Breguet in 2006 , the Rolex Syloxi appeared in 2014, and Richemont’s brands finally joined the party in 2017 with the Twinspir, which made its introduction in the Baume & Mercier Clifton Manual 1830.
But for what reason is silicon useful for hairsprings? Like all the other things, it comes down to how it acts inside nature and that it is so hard to manufacture.
Silicon hairsprings are better in nearly every category over Nivarox hairsprings as they have better temperature stability, are completely non-magnetic, have low inertia, are entirely homogeneous, and have better stun resistance. Silicon is more fragile, and it may shatter or break with hard enough stuns, yet these hairsprings have already performed beautifully for quite a long time (and outrageous stuns are as yet a problem for almost every watch).
Some attempts to tackle this have seen coatings added to the silicon structure, including diamond and silicon dioxide, which lead to more durable components.
Silicon components are made utilizing a photolithographic Deep Reactive Ion Etching (DRIE) measure that forms the silicon atom by atom (after utilizing photolithography to create the shape for it to adhere to), meaning the material is fundamentally great and also can be shaped in any capacity desired.
That ability has allowed for a blast of research into structures by and by as each aspect of the spring can be tailored for conditions pertaining to development, recurrence, and proposed use. Any ideal feature can be implicit, also diminishing the requirement for additional components and creating hairsprings that are lightyears ahead of the absolute first steel hairsprings.
And presently: yet considerably more hairspring advances
Given the quality and capabilities of silicon, one may imagine that brands may take it easy. Be that as it may, when they have ideas, creative people don’t have the ability to sit still.
In 2009, Cartier presented the ID One idea watch that was jam-packed with innovation. One of its elements was another new hairspring material called Zerodur, a glass ceramic material of carbon crystal that is, similar to silicon, manufactured utilizing the DRIE process.
This material, similar to silicon, is non-magnetic, homogeneous, stun resistant, and displays almost no thermal expansion. I have not seen an immediate comparison of any figures, however I imagine they are very close as far as capabilities.
Going an alternate course, in 2016 H. Moser & Cie & Precision Engineering AG acquainted a metal hairspring akin with the Rolex Parachrom utilizing a brand-new alloy, PE500. The material is an alloy of niobium, titanium, and oxygen that shows similar characteristics of being anti-magnetic, stun and temperature resistant, and formable – something still largely impossible with non-metallic hairsprings.
In 2017, Hong-Kong based Master Dynamic released its first patented hairspring made of silicon, yet with a fascinating new contort. I realize I recently referenced that shaping a non-metallic hairspring is largely impossible after it is created, yet Master Dynamic has found at least one way, and it comes down to angles (and some heat).
If you didn’t have the foggiest idea (I didn’t), silicon is anisotropic , meaning that based on the type of the cubic design and the atoms that make up said structure, the physical properties contrast contingent upon the orientation. And this can be utilized to advantage.
The distinction leads to the ability to cut the silicon wafers (the base material used to create the silicon components) at angles away from square, which Master Dynamic does at 45 degrees.
This produces a couple of advantages. The first is that slants in the material can actually be framed utilizing a subsequent scratching measure, something impractical with the regular DRIE measure. This coordinates stresses all through the part and avoid sharp edges that become fracture points.
But considerably more curiously, it allows the material to be manipulated, with the application of constant heat, to curve and wrinkle the finish of the silicon hairspring into a Breguet overcoil, making the Master Dynamic hairspring a combination of the most awesome aspects of both silicon and metallic hairsprings.
The end is collapsed over like a book to shape the overcoil, a vital part of the patent for the hairspring. A genuinely great advance in creating silicon fabrication techniques.
In 2018, the Swatch Group (proprietor of Nivarox ) released another new metallic hairspring in collaboration with Audemars Piguet called Nivachron , which made its presentation in the Swatch Flymagic early in 2019.
The reasoning behind going somewhat more outdated as far as material is an attempt to guarantee that future watchmakers will actually want to repair watches with these hairsprings without access to original parts or cutting edge DRIE equipment.
The Nivachron hairspring is titanium-based and amazingly paramagnetic , which leads to substantially less defenselessness to be affected by magnetic fields (probably a decrease by at least a factor of ten). Something else, the properties are likely similar to the Parachrom and PE500 materials.
Pushing the envelope hard: the TAG Heuer Isograph
But the innovation that has pushed the innovation forward the most has to be the latest improvement from TAG Heuer, a carbon-composite hairspring called Isograph that is based on carbon nanotubes and their incredible structural stability and lightness.
This carbon composite material was one of the features of the 2019 fair season for me.
So how could it be made and for what reason is it good?
First, the shape of the hairspring spiral is created out of carbon nanotubes utilizing a custom CVD measure. However the nanotubes are unfilled and should be combined with another material that underpins and ensures their construction, making it a composite.
Amorphous carbon is utilized to occupy in the space inside and between the carbon nanotubes, and thanks to truly stable covalent bonds it creates a functional material that behaves like a polymer composite (which is entirely flexible and versatile) however has physical properties of a crystalline construction (which is very strong).
Basically, the carbon composite hairsprings are better in many ways over the silicon, which was already better in many ways over the metallic choices: decreased thickness and affectability to stuns, non-magnetic, ultimately unadulterated with complete command over the shape and in this way the dynamic properties. It is all the more thermally variable compared to silicon, however it comes combined with an aluminum balance wheel to counterbalance that issue.
The carbon composite spring is incredible, demonstrating a level of research into new materials that has as of late become the standard for very good quality watchmaking. In the event that you don’t trust me, look at what Zenith is also doing with its Inventor technology.
Every new hairspring that has come out in the last two decades as the advanced era of watchmaking, research, and improvement has get going is rather incredible while thinking about where the humble hairspring began.
Each research path is an alternate way to approach the same problem, and each one comes with positives and negatives, allowing for decisions to be made for a variety of factors or constraints.
More importantly, the quartz emergency eventually led to a continuation of technical watchmaking as people eventually proceeded to grow new procedures, materials, and cycles trying to achieve the best mechanical watch possible.
Nobody really hopes to beat quartz (or atomic) watches for accuracy, yet that isn’t the point. The hairspring is a fundamental part of the logical strategy from the beginning of time and, with additional turns of events and innovation, we remain part of that lineage.
Hairsprings are still totally fundamental to mechanical watchmaking, and the additions throughout the last two decades are strongly impressive.
This overview of history and improvements scratches the surface of all that goes into – and has gone into – the delicate hairspring.
With the latest research and the improvements into other totally various kinds of oscillators – I’m taking a gander at you again, Zenith – there will be a great deal to watch out for over the course of the following two decades.
Technology drives innovation, and as devices, materials, and plans improve the sky really turns into the limit!
This story was first posted on July 28, 2019 at Hairsprings: Origins, Progress, And (Dare I Say) Exciting Future .
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