Watches and Waterproofness
Waterproof watches are mainly produced to protect the movement from external influences, especially from water, which is a source of constant concern for both Case Builders and Customers themselves.
Waterproofness is a feature not only required in the modern watch market, but especially sought after in the vintage and collection clock where the time spent between production and the use of good today is greater. Given that the water resistance of a watch is measured in atmospheres, it should be noted that divers, among the waterproof watches, were constructed for diving in sea water, with an average temperature of about 20 degrees and with a certain densities corresponding to a certain number of atmospheres (generally from 10 to 30 atm.), and were not designed for showering, sauna or bathing, as heat and steam produced by water above 30 ° C alter and deteriorate irretrievably the gaskets that are in natural rubber, compromising their functionality. To measure the degree of impermeability of a watch, with laboratory tests, a machine is used which, by vacuuming the glass case and buttons, and then compressing them under pressure, provides its hermetic value.
It is thus established that the waterproof data provided by the manufacturer covers that specific laboratory condition, let’s see what can happen to the wrist. A significant example is that of dip in the water with the wristwatch. In this case, the pressure acting on the watch is not only that relative to the depth that will be reached, but it is also necessary to sum up the one that comes from the height of the dive and the diver’s mass, so that the clock is behave exactly like a part of the diver’s body. It is important to remember that the pressure applied to the clock after a dip from a height of 1 meter of a person of 70 kg is by 5 atmospheres, and that it does not exercise uniformly across the chest, but mainly on the crown charging and buttons causing, due to physical laws, an additional increase of the same on the minimum surface of the watch.
Obviously, the dive situation is repeated with good proportions in many other cases, for example, with strong variations in temperature in winter skiing or on the summer beach by subduing gaskets to hard work to contain the ever-fearing water infiltration that contact with the movement, but above all the dial, can irreparably damage them with considerable losses in both economic and ripenability of oroginal pieces of the time.
So be careful so if you have a modern underwater waterproof watch, but in particular a collection vintage watch: you must follow all those precautions that will preserve over time its functionality and its value taking into account that you will not be able to claim a ‘absolute impermeability as we have seen it be easily overcome in critical stress strokes of many of its mechanical parts during a …… normal vacation.
Elvio Piva