210. watch-knowledge


Mechanical watches

中文

Question:

“I can’t seem to wear mechanical watches. Either they work sporadically or they don’t work at all on my wrist. Why is that?”

Luigi Zanneti, La Spezia, Italy

Answer by Professor J.C. Nicolet

There may be several reasons why a mechanical watch does not work. Most people who have this problem fall into one of the following categories.

• 1. An old and worn watch
• 2. A new but not water resistant watch
• 3. A manual-winding watch
• 4. Automatic and water resistant watches
• 5. Watches used under rigorous conditions
• And what about quartz watches?

1. An old and worn watch

Sometimes a person inherits a high quality watch which had worked well for more than 20 years when worn by its previous owner. Therefore, the new owner expects it to work as well for him. Well, it’s precisely because the timepiece has given good service for so long that it has become worn out and it deserves a good retirement alongside other “antiques”. Nobody expects modern exploits from a classic car, even if it was the best during its era. Why should we expect anything different from a watch?

2. A new but not water-resistant watch

A modern watch, even if housed in a magnificent case but one which is not water-resistant, can have problems when it is subjected to many of life’s daily activities. If worn during sleep, dust can enter the watch just from rubbing against the sheets. On the other hand, if the watch is removed before going to bed, its internal temperature decreases creating an airflow into its interior. As the air enters, so does the ambient dust, but unlike the air, these small particles do not leave.

Non water-resistant watches need more care that other timepieces and it is necessary to have them cleaned more often; usually once a year for small ladies’ models and once every two years for less delicate men’s watches. The use of perfume can also damage these watches as it can negatively affect the oil used to lubricate the delicate watch parts. Happily, synthetic oils used today are more resistant to the chemical in perfumes.

3. A manual-winding watch

All hand-wound mechanical watches, water-resistant or not must be wound regularly. Modern mechanical watches can often work for 40 to 50 hours between windings as compared to earlier models whose power-reserve was 30 to 36 hours. It is preferable, however to wind these watches every day and at about the same time because this will increase their precision.

Some wearers wind their watches whenever they happen to think of it, that is, several times during one day and not at all the following day. It is not wonder, then, that their timepieces sometimes stop. If this sounds like you, you should consider wearing a quartz or an automatic mechanical watch.

4. Automatic and water-resistant watches

Automatic and water-resistant watches can also present a number of problems that may be due to two factors:

- the wearer is too still,
- the wearer is too active.

People who are bedridden or confined to a chair because of illness, old age or, as is more likely the case, have low activity desk jobs, are not getting enough activity to rewind their automatic watch. When these people were healthier or just more active, their watches worked well, and it is perhaps difficult for them to admit that they are the reason for the poor operation of their faithful timepieces.

On the other hand, people who are too active, especially those who gesture a lot, tend to overwind their watches. They should remove their watches at night to better maintain the automatic winding mechanism. For those who are less active, they should wear their watches at night to keep them wound. Watchmakers have defined what they call the “winding speed” of manual-winding mechanical watches by using a very simple formula:

Winding speed = Time worn + time not worn / Time worn

Example: An unwound automatic watch (but wound just enough so that it will start functioning) is placed on the wrist and worn during 8 hours. Taken off, it will work for 16 hours without stopping. Therefore:

Winding speed= 3 ( 8 + 16 / 8)

A normal winding speed is between 2 and 3. Below 2, the watch may stop. Above 3, it will work very well at the beginning but the mechanism will wear out faster than normal.

5. Watches used under rigorous conditions

Everyone who wear a watch under difficult conditions should use a water-resistant or even a diver’s watch, especially when this watch is exposed to shocks, water (especially sea water), acids, dust or sudden temperature changes. Watches used under such conditions should be equipped with resistant crystals and anti-shock devices. For doing housework, it is also preferable to wear water-resistant timepieces because they can be unintentionally exposed to water.

The magnetic doors on refrigerators and cabinets may magnetize a watch if they come into direct contact with it. In these cases stainless steel offers better protection than a gold case. A magnetized watch works very poorly though, at first glance, it is not apparent that there is the problem.

And what about quartz watches?

Quartz watches with analog display, that is with dial and hands (the only kind of quartz watches manufactured in Switzerland) can be damaged by water and dust. If they are in a watertight case, they are well protected and should work fine as long as the battery is good. They are also less susceptible to the effect of magnetism than their mechanical counterparts. However, they have the additional disadvantage of stopping with no warning once the battery is low. If it has not been changed for a long time, it is a good idea to replace the battery before going on a trip or on vacation since the right one my be difficult to find outside major centers in most countries.

Swiss companies selling quartz watches are able to ensure good maintenance and repair as long as the component parts are available. Once parts are no longer being made, the watches cannot be repaired. On the other hand, mechanical watches can be repaired as long as a watchmaker can be found who is capable of handmaking defective parts. This, of course, is expensive, but if the watch is a collector’s item, it may be worth the effort.