Frequently Asked Questions
Learning More About Quality Watch Service
On these pages we respond to the questions that many of our customers ask us.
If you have a specific question that is not answered here, please contact us directly.
- What are the recommended service intervals?
- What should I do to ensure that my watch continues to provide excellent service for many years?
- Can I keep my watch on in the shower?
- How often should I have my watch tested for water-resistance?
- There is condensation on the inner surface of the crystal. What should I do?
- Can I go swimming with my watch?
- What should I do with my watch after swimming?
- Can I keep my watch in a safe for long periods?
- What is the difference between a self-winding and a manual-winding movement?
- What is the power reserve for a self-winding mechanical watch and how does it work?
- What is the difference between a "Chronograph" and a "Chronometer"?
- What criteria define a watch certified a "Chronometer"?
- What are the precision tolerances for other mechanical watches?
- What are the precision tolerances for most quartz watches ?
- What are the functions of the push-buttons on a Chronograph?
- What is the function of the helium escape valve on certain scuba diving watches, like the Omega Seamaster and the Rolex Sea Dweller?
- What do the initials "GMT" stand for?
- How do I use a Tachymeter (also referred to as a Tachometer)?
- Do you offer services worldwide?
What are the recommended service intervals?
Like any high-precision instrument, a watch needs to be serviced regularly in order to function optimally. This depends, however, entirely on the model, climate and the care taken by the watch's owner, as well as one's level of activity. In general, service intervals range from 4 and 5 years.
What should I do to ensure that my watch continues to provide excellent service for many years?
- Magnetic fields: avoid placing your watch on speakers or refrigerators, since these have strong magnetic fields.
- Bathing in the sea: always rinse your watch with warm water afterwards.
- Shocks: whether thermal or other, avoid them.
- Crown: screw it in carefully to ensure that no water enters the mechanism.
- Cleaning: for metal bracelets and for all water-resistant cases use a toothbrush with soapy water and a soft cloth for drying.
- Chemical products: avoid direct contact with solvents, detergents, perfumes, cosmetic products etc., since they may damage the bracelet, the case or the gaskets.
- Temperatures: avoid extreme temperatures (above 60C, or 140F, below 0C, or 32F) or extreme temperature changes.
Can I keep my watch on in the shower?
We advise you to take your water-resistant watch off when showering.
Soap and shower gels are designed to reduce the surface tension of water, in order to remove more easily particles of dirt from the skin. However, soapy water can also penetrate the minute gaps between the parts of the case and the seals. Please note this whenever you clean your watch.
Water can also be very detrimental to leather straps; certain types of leather (e.g. crocodile skin) should never be exposed to water.
How often should I have my watch tested for water-resistance?
A water-resistant wristwatch should be tested for water-resistance once a year and the seal replaced if necessary.
The constant influence of environmental factors such as perspiration, cosmetics or temperature can have a drastic effect on watch seals, which age with time and lose their sealant properties in the process. Sharp knocks can also adversely affect the water-resistance of your watch.
Significantly enough, professional divers have their watches checked for water-resistance at least once a year and resealed if necessary. We recommend this safety check for all water-resistant watches.
In the case of quartz watches, this test should be carried out after every battery change at the very least.
We recommend that you have your watch tested every year before your summer vacation.
There is condensation on the inner surface of the crystal. What should I do?
A watch with condensation under the crystal needs to be examined by a watchmaker without delay, even if the condensation disappears after a short time.
This is one of the worst things that can happen to a watch. It means that minute particles of water have penetrated the case but the seals are still tight enough to prevent the water from evaporating.
What you have on your wrist is in effect a miniature hot tub, where the water condenses at the coolest point. The constant damp atmosphere inside the case is very corrosive and, at worst, can destroy the movement.
Can I go swimming with my watch?
Certainly, if it's a water-resistant watch (and assuming you can swim, of course).
Before swimming, however, you should always ensure that the crown is screwed in tightly against the case. When the crown is in this position, the seals are pressed firmly against the case and crown making the watch more effectively protected against water. If the crown is not screwed in tightly, the seals are open inviting the danger of water entering the case.
Please note that water can be very detrimental to leather straps; certain types of leather (e.g. crocodile skin) should never come into contact with water.
What should I do with my watch after swimming?
If you go swimming in the sea or a chlorinated pool, afterwards, you should rinse off the watch with fresh water as soon as possible.
If salt or chlorinated water dries on the watch, the minerals contained crystallize, and act as an abrasive on the seals.
Important: You should never put your watch to dry in the sun.
Can I keep my watch in a safe for long periods?
If the place where you are storing your valued timepiece is reasonably dust-free, then yes. However, we do recommend the following:
- Mechanical watches (hand-wound, automatic):
Storing a mechanical watch for long periods is not a problem. However, watch lubricants gradually dry out with time. Excel Time Service strongly recommends that a watch not worn continuously be examined, nonetheless, every five or six years. Doing so will not only ensure future performance of your valued timepiece, but also it will help maintain its value.
- Quartz watches:
If you plan to safe-keep your quartz watch for more than a year, we strongly recommend having the battery removed, as a safety precaution. Dead batteries tend to leak if they remain in the watch. The acids released can severely damage the movement. Excel Time Service is pleased to offer this important preventive measure on a complimentary basis.
What is the difference between a self-winding and a manual-winding movement?
The difference between these two movements is the way in which the watch is wound up.
Manual-winding watches must be wound by hand every day. Self-winding watches are wound by an internal rotor, which responds to wrist movements.
Self-winding watches usually have a power reserve of at least 40 hours and therefore have sufficient energy reserves to maintain a stable rate when the watch is not being worn (e.g. overnight).
What is the power reserve for a self-winding mechanical watch and how does it work?
The functioning of a self-winding mechanical movement depends on the wrist movements of the wearer. When fully wound, a watch will usually have a power reserve of around 40 hours.
Since the watch's self-winding mechanism is directly linked to the wearer's activity, 10 to 12 hours' wear should be sufficient to generate a power reserve of 20 hours or more. This ensures that the watch will continue to run throughout the night, for example.
However, if a watch is not worn for several days, we recommend you wind the watch manually for around 15 rotations of the crown (clockwise) to ensure the best possible rate from the outset.
What is the difference between a "Chronograph" and a "Chronometer"?
A chronograph is a watch with hands that display hours, minutes and seconds, together with a mechanism for measuring elapsed time by means of a central chronograph hand, which records seconds, and 30-minute and 12-hour totalisers.
A chronometer is a watch that has obtained an official rate certificate from the C.O.S.C. (Official Swiss Chronometer Testing Institute) after having passed precision tests in different positions and at different temperatures, as well as water-resistance tests. These tests are conducted over a 15-day period.
What criteria define a watch certified a "Chronometer"?
The designation "chronometer" is registered and used only if an independent inspection authority has tested the movement of a watch.
In Switzerland, this inspection authority is better known as the "Swiss Official Chronometer Testing Institute" or "C.O.S.C."
The C.O.S.C. tests the movements submitted to it for their accuracy over a period of 15 days: the first 10 days at room temperature and for the last 5 days at a range of different temperatures.
The measured timekeeping deviations must lie within pre-defined tolerances, usually of -4/+6 seconds per day, or a precision of 99.99%, the highest precision attainable by a mechanical movement. Only then is a "Swiss Official Chronometer" certificate issued for the movement.
What are the precision tolerances for other mechanical watches?
The precision of a mechanical movement depends on the individual habits of the wearer and can therefore vary.
The majority of watches that do not have a chronometer certificate have average precision tolerances of between -1/+11 seconds per day.
What are the precision tolerances for most quartz watches ?
Ambient temperature may affect the precision of quartz movements, which can lead to variations of between -0.5 and +0.7 seconds per day.
What are the functions of the push-buttons on a Chronograph?
The push-button at 2 o'clock is to start or stop the chronograph function and the push-button at 4 o'clock is for resetting the chronograph.
What is the function of the helium escape valve on certain scuba diving watches, like the Omega Seamaster and the Rolex Sea Dweller?
The helium escape valve was specially developed by Omega and Rolex for use by professional divers.
During deep-sea dives lasting several days, divers operate from diving bells. Prior to surfacing, these bells are filled with a mixture of helium and oxygen.
The helium molecules are lighter than air and can therefore penetrate the watch in sufficient quantity to push out the crystal at atmospheric pressure levels.
This can be avoided by opening the valve during resurfacing, which allows the helium to escape but prevents water from entering the watch.
What do the initials "GMT" stand for?
Abbreviation for "Greenwich Mean Time."
As a feature of watches, it means that two or more time zones are displayed. In this case, the second time may be read from a hand making a full rotation in a 24-hour ring (thereby also indicating whether it is a.m. or p.m. in that zone).
How do I use a Tachymeter (also referred to as a Tachometer)?
A tachymeter is an instrument for measuring speed. It is a chronograph with a graduated dial on which speed is read in kilometers per hour based on 1000 meters distance.
How to read an observation on the tachymeter: Only the central chronograph seconds-hand is used. For observations of a longer duration, the indications of the timers (minutes and hours) count.
Example for calculating the speed of a car: The chronograph indicates that the distance of one kilometer has been covered in 30 seconds. The corresponding point on the tachymeter scale indicates 120. The speed is therefore 120 km per hour.
Do you offer services worldwide?
Yes, we are pleased to offer watch repair and after-sales services not only to our customers in the United States, but also in Canada, Latin America, the Caribbean, Europe, Japan and the rest of the world.
Wherever you live, Excel Time Service can help. Our premises are fully insured including a vault, we offer safe and secure shipping and handling of your precious timepiece, and quick turnaround services.