Anatomy of a wristwatch: A master watchmaker explains what goes on under the hood

 
Alex Doak

Mechanical timepieces have the complexity and allure of tiny, self-contained universes. We asked a master watchmaker to explain what goes on under the hood.

It was Jaguar’s founding father, William Lyons, who famously said “the car is the closest thing we will ever create to something that is alive.” But the late, great virtuoso English watchmaker George Daniels – a vintage Bentley collector himself – elevated the humble mechanical timepiece to a status outreaching even life itself. At just five years old, he prised off the back of a pocket watch with a bread knife, and “what I saw inside the case was the centre of the universe,” he recalls. “It had a curious completeness. The contents started at one end with the mainspring and proceeded in a circle to the inside of the case to the vibrating balance wheel. And it was a complete composite world; it didn’t seem to need any assistance from the outside; it was perfectly happy to work quietly away in its closed case.”
Herein lies the deep satisfaction of mechanical watches. Many will spend their thousands on a watch because it articulates their status or fashion sense. But other – perhaps more perceptive – collectors are buying into the technique required to form and finely hone the many hundreds of components by hand (indeed, Daniels had mastered all 34 crafts necessary to do this). The appeal of a mechanical watch over a battery-powered quartz one is the fact you can have a living, breathing entity on your wrist, with a heartbeat tick-tick-ticking inside.
Just take a moment to look at the diagram of TAG Heuer’s Calibre 1887 chronograph movement (pictured opposite): complex, delicately assembled wheels, springs, levers and cogs – still based on a 200-year-old technological principle. In fact, every mechanical watch to this day is based on this same premise – a mainspring powering a precisely ratioed geartrain to which the hands are attached, whose running speed is regulated by a ticking “escapement”, which ekes out the mainspring’s torque tooth by tooth. We asked the watchmakers of Bond Street’s Wempe emporium to talk us through the inner workings of the watch universe, piece by piece.


A blown-up Tag Calibre 1887

1. WINDING ROTOR
A weighted arm that spins with the movement of the visible arms, winding the mainspring via a ratchet. Watches with rotors are “automatic”; watches without are “manual”, because you have to wind them yourself.
2. COLUMN WHEEL
The hub of the chronograph mechanism, governing start, stop and reset functions with a super-soft click of the button at two o’clock.
3. OSCILLATING PINION
A coupling system patented by Edouard Heuer in 1887 (thus the origin of this new calibre’s name) that enables the chronograph mechanism to engage with the main movement’s energy train with precision and lightning speed: an incredible 2/1,000th of a second.
4. BARREL
The watch’s source of power, kept fully charged by the rotor. A spring is tightly coiled inside, forcing the toothed barrel to drive the geartrain.
5. BALANCE WHEEL
Oscillating four times a seconds, this is the watch’s equivalent of a pendulum, suspended on a tiny hairspring, regulating the escapement’s rate of “tick”.
6. ESCAPEMENT
A locking/unlocking lever mechanism that releases the geartrain tooth by tooth at a rate governed by the oscillation of the balance wheel.
7. JEWEL BEARINGS
The 39 pink “dots” are actually synthetic, oiled rubies, providing durable yet virtually frictionless pivot points.
8. GEARTRAIN
What the hours, minutes and seconds hands are attached to. Powered by the mainspring at one end of the train, these three brass wheels turn at rate governed by the escapement at the other end.


A watchmaker working on a Tag Heuer

The surging interest in mechanical watches (worth over £11bn a year to the Swiss industry) is creating a problem: there aren’t enough watchmakers to keep up with the demand for repairing and servicing them all. This can have dire consequences: without the recommended full service every three to five years, lubricating oils can harden to a varnish at critical pivot points, causing friction to delicate parts; these can then come loose, wreaking havoc with your watch’s innards.
The notion of your local watchmaker is a dying one, but in-house watchmakers at the finer watch emporia are now replacing them. Germany’s Wempe group were the first to bring their watchmakers out of the attic and onto the shopfloor. At its Bond Street store, three watchmakers tinker incessantly at the rear of the ground floor, qualified to repair and service Rolex, Patek Philippe, Officine Panerai and TAG Heuer among others.
It may cost around £400 for a service, but put it this way: the engine of a mechanical watch is under far more duress, in relative terms, than your average car, which is rarely required to run at a constant full pelt. A service every five years suddenly seems quite sensible. “The public are under the impression,” says Wempe watchmaker Graham Forster, “that you just take out the movement and give the case a quick clean. But it’s a very complicated procedure.
“Everything is stripped down to its bare bones, piece by piece, with each component of the movement individually checked for wear and replaced if necessary. Then the parts are placed in an automatic cleaning machine – four tanks of ultrasonically charged cleaning and rinse fluids.” While the machine does its thing, Forster cleans and polishes the case, buffing out any scratches, before beginning the painstaking process of tweezering back together, re-oiling as he goes, the hundreds of components. All of which takes the best part of a day for a single watch.
“After we’ve regulated the watch twice for precise timekeeping,” Forster says, “every serviced watch goes onto a winder and we check it’s keeping good time every morning for a whole week. Only after that week’s quality control do we hand it back to the customer.”
Foster has a few more tips for owners of fine watches: have your timepiece checked for water resistance every couple of years, and have any seals replaced if necessary. Don’t wear your watch loosely – as well as looking gauche, it can cause premature ageing in the bracelet links. And don’t use soap to clean it – just a damp cloth, or, ideally, alcohol wipes.
Remember, that mechanical watch you own is a ticking miniature universe. Take care of it and it will still be spinning long after you’ve left this mortal coil.