Feature: What does ‘automatic’ mean in a watch?
Automatic wristwatches revolutionised the industry when they emerged in the 1930s and are now the most common type of mechanical timepiece. But why are they so popular? Do they ever need batteries? And will they go on ticking for all eternity? We put these questions and more to our trusted experts.
A brief history of automatic watches
Rolex certainly perfected and championed the automatic wristwatch, but the person credited with inventing the first self-winding movement powered by an oscillating weight—more of which later—is the pioneering Swiss watchmaker Abraham-Louis Perrelet in the 1770s.
Abraham-Louis Perrelet, inventor of the self-winding watch
The watchmakers Hubert Sarton and the great Abraham-Louis Breguet were two of several watchmakers who further developed the technology over the following century before a Parisian watchmaker called Leon Leroy came up with the idea of a self-winding wristwatch in 1922, making a small batch for a private client.
A year later, an English watch repairer by the name of John Harwood developed his own version of an automatic wristwatch that could be mass-produced. His design used a centrally mounted oscillating weight—or rotor—much like today’s automatic watches.
Yet instead of being able to move propellor-like through 360 degrees, the weight swung through 180 degrees, bumping back and forth off a pair of spring-loaded buffers. Interestingly, it had no crown, meaning the time had to be set via the bezel.
This Harwood model proved instrumental in the development of the self-winding wristwatch. Image courtesy of Bonhams
Harwood secured funding and applied for patents for his design in several countries. The watch was well received on both sides of the Atlantic, with even Blancpain putting in an order for Harwood movements.
Yet despite industry acclaim and respectable sales (the first and only series of watches sold 34,000 pieces), production costs were high and the disastrous Wall Street Crash of 1929 led to Harwood’s company filing for bankruptcy before being wound up in 1932.
The innovative 'perpetual' movement that laid the bedrock for Rolex's success
It was left to Rolex to pick up where Harwood left off, and together with its movement maker Aegler it invented the self-winding ‘perpetual’ movement in 1931, initially mounting a free-spinning rotor on to an existing manual-wind movement (see above).
The resulting Oyster Perpetual—the world’s first water-resistant automatic watch—is now considered the foundation for Rolex’s unparalleled success.
What are the disadvantages of automatic watches?
Case sizes tend to be bulkier with automatic watches as the movement also has to accommodate the aforementioned winding rotor, or oscillating weight.
The rotor of a modern Oyster Perpetual
If it’s an automatic chronograph movement then the the case becomes thicker still due to the extra components needed for the chronograph. For many people, a thick watch case rising tower-like off the wrist is not an attractive proposition—which is why brands are forever working on producing slimmer movements. Literally credit card thin, in some instances.
Richard Mille's record-breaking wafer-thin manual-wind movement
Watchmakers can get around this problem by using a micro-rotor instead of a regular-sized rotor, which takes up less space. Naturally the slimmest watches tend to be manual-wind models with no complications.
A micro-rotor, seen here in gold, helps to slim down a watch's movement
Does the sound of a watch bother you? If so, try out an automatic watch before you buy it. On some watches, the sound of an oscillating rotor swinging around in the case can be quite prominent—on old or cheaper watches you might even call it “clunky”.
While it’s not exactly comparable to your next-door neighbour playing drums and drilling holes in the wall, the noise could prove irritating.
One major disadvantage of any mechanical watch, at least compared to a quartz watch, is accuracy. Remember, no mechanical watch—automatic or manual-wind—can ever be as accurate as a quality quartz-powered one.
How does an automatic watch work?
An automatic watch relies entirely on the natural motion of its wearer to work. The wearer’s kinetic energy is transferred to the mainspring via a centrally mounted, semi-circular weight called a rotor—or oscillating weight—which pivots freely through 360-degrees.
The winding rotor of a TAG Heuer watch seen through the exhibition case back
Even the slightest movement, from scratching your nose to typing on a keyboard, is enough to nudge the rotor, thus winding the mainspring and automatically charging the watch while it’s worn.
As with a hand-wound watch, the mainspring then releases its stored energy via the gear train before the escapement steps in to perform its timekeeping job of releasing the gear train to move forward in precise increments, advancing the watch’s hands.
The winding rotor on high-end automatic watch movements is often made from precious metal and intricately decorated
These days, many watches have what’s called an exhibition case back, allowing the movement to be viewed when you remove the watch from your wrist. The winding rotors on these watches are sometimes made from gold and decorated with hand-engraved guilloche work, cote de Geneve striping, the brand’s logo, or all three.
What is the point of an automatic watch?
The automatic wristwatch emerged as a more convenient alternative to manual-wind watches, which required the wearer to “charge” the mainspring by winding it up (i.e., gripping the crown between two fingers and rotating it) every day or so—that’s if they remembered to do so in the first place.
That’s the trouble with a manual-wind watch. If you forget to wind it, it simply stops once the mainspring is fully unwound, requiring the wearer to check and set the correct time before going through the process of winding it up again by hand.
An automatic watch, however, will keep on going, as long as the wearer keeps moving, only requiring the occasional time adjustment.
Though manual-wind watches are an inconvenience for some, others see it as a great opportunity to engage with their watch. They love the pleasing sound of that winding stem being cranked, with every timepiece sounding and feeling ever so slightly different.
Does an automatic watch need a battery?
Automatic watches are fully mechanical and require no battery. Even the hybrid Spring Drive movements produced by the Japanese brand Grand Seiko, which combine mechanical and quartz technology, don’t require an actual battery to power the watch.
Yes, it has a rotor, but automatic Spring Drive movements are not fully mechanical
By the way, an easy way to tell if a watch is mechanical or quartz-powered is by the seconds hand. With a mechanical watch it appears to “sweep”, while on a quartz watch it “ticks” once per second. That said, there are very rare exceptions to this rule, such as the long-discontinued Rolex Tru-Beat, or Jaeger-LeCoultre's Geophysic True Second.
Both of these are unusual in that they are mechanical, self-winding watches with a ticking (or "deadbeat") seconds hand, as opposed to a sweeping one.
Are automatic watches more expensive than battery watches?
Generally, mechanical watches of any kind—whether manual-wind or automatic—cost more than their battery-powered counterparts. This might be considered strange given that a quartz watch is more technologically advanced than a mechanical one.
But since the 1990s mechanical watches have been seen as a more luxurious product and less "mass market" than quartz. They’re often made of precious metals and feature components that have been meticulously engraved, polished or finished by human hand, rather than a series of machines in an identikit factory that churns out millions of products a day.
F.P. Journe's Elegante watch. Battery-powered but definitely not mass market
There are exceptions, of course. This quartz-powered Elegante watch by the Swiss brand F.P. Journe is a great example of a high-end luxury quartz watch, selling for around £40k.
Can you sleep with an automatic watch?
Wearing your automatic watch while you sleep is fine, as is leaving it on the bedside cabinet overnight. After an automatic watch has been worn for a few hours or days, it will have built up a power reserve so that it will keep on ticking even if you remove it from your wrist for a day or two. A fully-wound watch's power reserve can be anything from 38 hours to a few weeks, depending on the model.
Do automatic watches last long?
Given how easy it is to find vintage automatic watches from the 1950s in good working condition, it’s fair to say that most modern examples should still function properly after half a century and beyond. You’ll even find examples from as far back as the 1930s that still keep good time, especially by reputable brands like Rolex.
A 1970s stalwart from Rolex, this automatic GMT-Master is still going strong
With regular servicing and a little luck, an automatic watch from a reputable luxury brand should outlive its wearer, and maybe even its wearer’s grandchildren and great-grandchildren.
Most modern luxury watches are built even more robustly than those from the past, with superior metals, anti-magnetic qualities, better lubricants and higher water resistance.
Your automatic watch will take a beating and is built to last. And that's more than you can say for all those plastic smart watches heading for landfill sites after five years.
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Shop pre-owned F.P. Journe watches
