We all have our eyes on clocks every day but perhaps not everyone knows exactly how they work. For example: why do the second hands move jerkily in some watches while in others they move much more smoothly? And what is the mechanical component responsible for the classic “tic tac”? In this video we clarify these and many other aspects, dismantling a mechanical watch and also explaining what differences there are compared to a quartz one.
Mechanical watches: comparison of types and functioning
There are two variations of mechanical watches: those with manual winding and those with automatic winding. In those a load manualenergy is supplied by turning the crown – the small side knob, the same one used to set the hours and minutes. This rotation progressively winds the main spring: a very thin sheet of metal almost a meter long, enclosed inside a component called barrel. It can be compared to the petrol tank of the watch: the more the mainspring is wound, the more energy has stored. Once wound, it gradually releases it, setting in motion the gear train and, consequently, the hands. In watches automatic the basic principle is the same – winding the spring – but you don’t have to do it by hand. Inside the mechanism there is an element called rotor (or oscillating mass): a metallic crescent that oscillates every time you move your wrist, automatically winding the watch during normal daily activities.
The gear train
Once wound, the spring sets the train Of gearsor the set of toothed wheels that transmits movement to the hands. Each wheel is connected to a different hand: the main one manages the minutesa faster i secondswhile the hours they are entrusted to a series of reduction wheels that slow down their movement. The problem, however, is that if the system stopped here, the spring would release all its energy in a few seconds, causing the hands to spin uncontrollably. This is where the most important component of the entire watch comes into play: the exhaust.
The escapement
The exhaust it is, in essence, the clock brake. Its job is to regulate the amount of energy that the spring distributes to each component, moment by moment. At the bottom of the gear train is the escape wheel, which would be free to spin uncontrollably if it were not blocked by a wheel-shaped element. Y called Still. At its ends, the anchor bears two small teeth in ruby syntheticwho alternate locking and releasing the wheel at precise and regular intervals. This mechanism is directly linked to the barbell: a wheel inside which there is a spiral spring as thin as a human hair. The spiral winds and unwinds rhythmically, and it is precisely this oscillation that marks the passage of time.
But the anchor isn’t just for braking: every time a tooth on the escape wheel slips away from the ruby, it transmits a small push to the balance wheel, keeping its beat alive. It is from this movement that the characteristic is born tic tac of the mechanical watch – which repeats in some models over 28,000 times in one hour.
The problem of magnetism
There spiral of barbell it is the most delicate component of the entire watch, because it is the one that determines its precision. If the watch is exposed to an electromagnetic field – which is far from rare in the age of smartphones and computers – the hairspring risks oscillating at an altered rhythm, compromising the measurement of time.
The solution adopted by the watch industry is the use of non-magnetic materials for the hairspring, such as siliconor the Nivachrona titanium alloy that guarantees resistance to magnetic fields, impacts and temperature variations.
The rubies
In mechanical movements it is common to find small pink stones nestled between the gears. It’s about rubies syntheticand their presence has a purely functional reason.
The gear pins, constantly turning, would wear out quickly if they rested directly on the metal. Synthetic rubies act as bearings: being almost as hard as diamonds, they wear very little. Furthermore, their surface is machined with extreme precision, making it capable of retaining the lubricating oil by capillarity and thus guaranteeing excellent performance over time.
Quartz watches: characteristics and differences with mechanical watches
Quartz watches work on a completely different principle, based on a physical property called piezoelectricity. Inside the watch there is a shaped quartz plate tuning fork (a U with a stem). When subjected to an electrical impulse – generally supplied by a battery – the plate flexes; when the impulse ceases, it returns to the original position. This makes it vibrate continuously and precisely. The clock chip is programmed to know that every 32,768 vibrations corresponds to exactly one second. Every time that number is reached, the second hand advances by one click – which is why in quartz watches the movement is shotsnot continuous as in mechanics.
There are also solar versions: the dial or glass houses photovoltaic cells that capture light energy and store it in a rechargeable battery, eliminating the need to replace the battery.
Let’s start with precision. Quartz watches, having a chip inside them, are more precise of mechanical ones. In fact, if mechanical ones can have variations of a few seconds every day, quartz ones reduce the variation to a few seconds per month. Even when it comes to autonomy, the quartz ones are certainly more practical: a battery lasts on average between 2 and 5 yearsand if one has a sundial this value is potentially even higher. Mechanical watches, on the other hand, have a “power reserve” that varies based on the movement. This for example is the Powermatic 80 by Tissot with a durability up to 80 hoursso basically if you take off your watch on Friday evening, on Monday morning you will find it still working.
As for the costs, the mechanical ones are technically much more complex – we saw it with our own eyes. So it goes without saying that they tend to be more expensive. And in reality, however, it is precisely this complexity that makes them so fascinating. So: which one to choose? It all depends on you, your habits and, above all, the type of bond you want to establish with the object you wear on your wrist.
