How we Work
On Time Watch Service is an established Watch Repair and Service Business in Cape Town, South Africa.
We have experienced and time tested processed in place to ensure the best customer service.
Below are answers to common questions asked by our clients…
FAQ – Watch Care & Handling
Why should mechanical watches be serviced on a regular basis?
How often does a mechanical watch need to be serviced?
What happens to it when it goes for a service?
Where should you take your watch to be repaired or serviced?
If the watch is under warranty, the warranty may be invalid unless you take it to a service centre authorized by the manufacturer. You can get a list of authorized repair centres from the various manufacturer websites. If the warranty has expired, you can take it either to an authorized centre or to a reputable repair shop such as “On Time Watch Services“.
How much does it cost?
How long does my watch have to stay in the workshop?
Do quartz watches have to be serviced regularly, like mechanical watches?
No. Quartz watch movements do not need nearly as much maintenance as mechanical ones. That’s because they have far fewer moving parts -just the gears that move the hands. (A digital watch has no moving parts at all). All that most quartz watches require is that when the case is opened for a battery change it is cleaned of accumulated dirt. However, some expensive quartz analogue watch movements should have their gear train lubricated every 8 to 10 years. For inexpensive quartz watches, this isn’t worth doing.
Do you need to wind a mechanical watches every day?
Does it matter which way you turn the crown when you set the time of a watch?
Will heat and cold affect the accuracy of a watch?
Heat and cold will affect the time-keeping ability of a quartz watch. Quartz crystals, whose extremely steady vibrations are responsible for the unrivalled accuracy of quartz watches, are cut so they perform optimally at room temperature. A temperature of 100°F – 37°C will throw the timing off by about 1 second a day, as will one of 32°F- 0°C. Extreme temperature will also affect the accuracy of a mechanical watch, but not as much as other factors. One reason is that hot and cold cause the metal parts of a watch movement to expand and contract (though advances in metallurgy have made this less of a problem than in the past). Another reason is that heat and cold affect the viscosity of the oil that lubricates the movement, and thereby affect the movement’s accuracy.
FAQ – Water Resistance
What makes a watch water-resistant?
There are several features that help make a watch water resistant. The most important is the gaskets, or O rings made of rubber, nylon or Teflon which form a watertight seal at the joints where the crystal, case back and crown meet the case. If the watch is a chronograph, the chronograph pushers will also have gaskets. In addition water resistant watch cases are lined with a sealant, applied in the form of a quick-hardening liquid, which helps keep water out. The thickness and material of the case is also a big factor in determining whether a watch can safely be worn under water. The case must be sturdy enough to withstand pressure without caving in, in general, this means a steel or titanium case or a steel case plated with gold, manufacturers say. Solid gold cases can be water-resistant provided they are sufficiently thick. A screwed down crown forms a watertight seal much like the seal between a jar and its lid.
Why are watches never labeled as "Waterproof" (incl. Deep Sea Diving Watches)?
My watch is labelled "Water-resistant to 50 meters". Why can't I wear it for snorkeling or diving?
The different levels of water resistance as expressed in meters are only theoretical. They refer to the depth at which a watch will keep out water if both watch and the water are perfectly motionless. These conditions, of course, are never met in the real swimmer’s or diver’s world. In real life, the movement of the wearer’s arm through the water increases the pressure on the watch dramatically; so it cannot be worn to the depths indicated by lab testing machines.
What are the various levels of water-resistance?
Watches with the lowest level of water resistance are labelled simply “Water-Resistant.” They can withstand splashes of water but should not be submerged. Above that (or below it, literally speaking), the most common designations are:
- 50 meters (1 meter is about 3.3 foot), which means the watch is suitable for swimming
- 100 meters; indicating it can be worn snorkeling
- 200 meters, suitable for recreational scuba diving and, believe it or not
- 1000 meters (roughly three- fifths of a mile)
Watches in this last category can endure deep-sea diving. Their gaskets are made of materials that can withstand the helium used in decompression chambers. Some have valves that let the wearer release the helium that has seeped into the watch so the case will not explode as the watch and diver adjust to normal atmospheric conditions.
What does the abbreviation ATM used in labelling a watch's water-resistance mean?
It stands for “Atmosphere” and it is equal to 10 meters of water pressure. Another word for atmosphere is “Bar” which is often used in Europe. The deeper you go, so the proportions change.
Is water resistance permanent?
No. Water resistance depends on several factors (see question 1) some of which can be affected by wear or simply by time. Gaskets can become corroded or misshapen, case dented or crystals loose or broken. That is why your watch, like a car and your teeth needs preventive maintenance.
How often does water resistance need to be checked?
At least once a year. Most of the manufacturers say water resistance needs to be tested every time the case back is opened, because opening the case back can dislodge the gasket. This rule applies even to a simple battery change. (Many service centres also change the gaskets when the watch comes in for a service.) You should only take your watch to a well-known service centre that guarantees work done.
How is water resistance tested?
There are basically two ways of machine testing water resistance, referred to as ” dry” or “wet” testing. In the former the watch is subjected to air pressure and measurements taken to see whether the case expands as a result of air leaking into the case. If it does, the watch is not water resistant. In one type of “wet” testing, the watch is first subjected to air pressure, and then submerged in water. If air bubbles come out of the case when it is underwater, it means air seeped into the watch before it was submerged, and it is therefore not water resist. In another type, the watch is placed in small water filled chamber, which is then subjected to pressure from a piston. If water gets in into the watch, it is not water resist. (This is obviously the most risky form of testing)
Can I wear my water resistant watch in the hot tub?
No. Exposing your watch to heat, whether it is in a hot tub or a sauna can cause the gaskets to lose their shape and ability to keep water out.
What, besides extreme temperatures, will jeopardize my watch's water resistance?
My divers watch came with a leather strap. Will water harm it?
It may. Wearing a leather strap in the pool is not generally recommended. (It is like wearing your shoes when swimming) Instead, choose a metal, plastic, rubber or nylon strap. However, some strap manufacturers do offer straps that are specially treated. Check your warranty before swimming.
FAQ – Swiss Chronometers
What is a chronometer?
A chronometer is an extremely accurate watch or clock. The name is derived from the Greek words (chronos + metron) meaning to measure time. A Swiss chronometer is a watch, usually mechanical, the precision of which has been tested and verified by an official Swiss watch-testing bureau. The watch comes with a ratings certificate issued by the institute. The chronometer designation is a badge of honour, proof that the watch is of superior quality.
How does a watch earn the title of chronometer?
Who conducts the tests?
Switzerland has been officially testing chronometers since 1878. COSC as it exists today was founded in 1973.
How is the movement tested?
COSC conducts elaborate precision tests on the movements using cameras and computers, which analyze the data collected. COSC performs seven different tests. Failure to meet the minimum standard in any one of the tests means that a movement is rejected. The tests are complicated. Here is an attempt at a simple summary:
- Mean Daily Rate: After 10 days of tests, the mean daily rate of the movement must be within the range of -4 to +6 seconds per day. COSC determines the mean daily rate by subtracting the time indicated by the movement 24 hours earlier from the time indicated on the day of observation.
- Mean Variation in Rates: COSC observes the movement’s rate in five different positions (two horizontal, three vertical) each day over 10 days for a total of 50 rates. The mean variation in rates can be no more than 2 seconds.
- Greatest Variation in Rates: The greatest of the five variations in rates in the five positions can be no more than 5 seconds per day.
- Horizontal and Vertical Difference: COSC subtracts the average of the rates in the vertical position (on the first and second days) from the average of the rates in the horizontal position (on the ninth and tenth days). The difference must be no more than -6 to +8 seconds.
- Greatest Deviation in Rates: The difference between the greatest daily rate and the mean daily test rate can be no more than 10 seconds per day.
- Rate Variation Due to Temperature: COSC tests the movement’s rate at 8 degrees Celsius (46 degrees Fahrenheit) and at 38 degrees C (100 degrees F). It subtracts the cold temperature rate from the hot temperature rate and divide by 30. The variation must be no more than 0.6 seconds per day.
- Resumption of the rate: This is obtained by subtracting the average mean daily rate of the first two days of testing from the mean daily rate of the last test day. The resumption of rate can be no more than 5 seconds. Simple, isn’t it? If a movement meets the standards, COSC issues a certificate designating as a “chronometer.”
How many movements do COSC test each year?
In 1995, COSC tested 844,043 movements. That was down slightly (-4.5%) from 1994 when a record 883,714 movements were submitted for testing.
How many certificates do COSC issue each year?
In 1995, COSC issued 814,868 certificates, 96.5% of those submitted. That means chronometers represent about 2% of Switzerland’s total production of complete watches.
Why are most chronometers mechanical watches?
Just one-third of 1% of the movements submitted for testing in 1995 (3,026 total) were quartz movements. That is because electronic quartz technology is by definition an ultra-precise form of timekeeping and there is less need to demonstrate a quartz watch’s accuracy. This is not the case with mechanical watches. COSC has developed stringent regulations which quartz watches must pass before they can be called chronometers. Worth noting: by far the leader in Swiss quartz chronometers in 1995 with two-thirds of the total certificates issued was Krieger Watch Corp. of Miami Beach, Fla.
Do many watch manufacturers apply for chronometer certificates each year?
More than 60 manufacturers submitted movements to COSC in 1995.
Is there a demand for chronometers?
Despite the drop in requests in 1995, there has been a surge of watch company applications for chronometer certification in this decade. COSC data shows that the number of movements submitted bottomed out in 1976 at 225,712. Requests did not pass the 300,000 unit mark again until 1984. It rose steadily throughout the late 1980s but has soared in the 1990s, reflecting the strength of Rolex, in particular, and the general revival of Swiss mechanical watches in world markets. In 1990, the number of movements submitted to COSC passed the 600,000-unit mark for the first time. By 1994, the number had reached 883,714, an increase of 43.5% over 1990.
Which firm is the leader in production of Swiss chronometers?
Rolex is the undisputed chronometer king. An amazing 83% of all chronometer certificates issued by COSC in 1995 went to Rolex–more than 675,000 of them. You get some sense of Rolex’s dominance when you realize that only five firms (one of them a group, really) produce more than 6,000 chronometers a year. The second largest producer of chronometers is Omega (51,638 certificates in 2000), followed by TAG Heuer (31,135 certificates), the Cartier Group (6,393) and Bulgari (6,056).
What is the difference between a chronometer and a chronograph?
The terms sound similar but they have nothing to do with each other. A chronometer, as we have seen, is a superior timekeeper. A chronograph is a watch with a stopwatch function.
What is a marine chronometer?
A marine chronometer is an instrument used on a ship at sea to determine the longitude by measuring the time. It was developed in the 18th century.
FAQ – Watch Crystals
What is a watch crystal?
What are watch crystals made of?
They can be made of any of three materials:
- Plexiglass (a clear, lightweight type of plastic)
- ordinary glass as used in windows, and usually referred to in the watch business as a “Mineral Glass”
- synthetic Sapphire
Some crystals are made of both mineral and sapphire glass. Seiko for example, makes some watches with crystals made of mineral glass covered with a layer of synthetic sapphire. Seiko call this composite material “Sapphlex.”
What are the advantages and disadvantages of each material?
Plexiglass, as you would expect, is the least expensive. It is also the least likely to shatter and the most likely to become scratched. Mineral glass, even though a tempering process has hardened it, is more likely to break than a Plexiglass. But it is also more scratch-resistant. Synthetic sapphire is the most expensive glass crystal material and the most scratch resistant. Because it is so hard, it is also brittle, and shatters more easily than mineral or Plexiglass.
What exactly is synthetic sapphire?
It is a very hard, transparent material made by crystallizing aluminium oxide at very high temperatures. Chemically, synthetic sapphire is the same as the natural sapphire used in jewellery, but without the colouring agents that give the gemstone its various hues. When it is heated, the synthetic sapphire forms round masses that are sliced into pieces with diamond-coated saws. These disks are then ground and polished into watch crystals. (One reason sapphire crystals are relatively expensive is that the tools required to make them are costly.) Sapphire (whether natural or synthetic) is one of the hardest substances on earth. It measures 9 on the Mohs scale, which is a system for rating the relative hardness of various materials. (Diamonds measure 10, the highest rating.) Watch crystals made of synthetic sapphire are often marketed as “scratch resistant”, meaning they are very difficult-but not impossible to scratch. Diamonds can scratch them; so can man-made materials that incorporate silicon carbide, with a Mohs rating of between 9 and 10, is, like diamond, harder than sapphire. These materials are sometimes used to make simulated stone surfaces for furniture or walls. The watch wearer should note that accidentally scraping a sapphire crystal against such a surface could cause a scratch.
Can you tell if a crystal is made of sapphire by looking at it?
No. Mineral glass and sapphire generally look the same. A sure way to tell them apart is with a scratch test. “You would not be very popular if you have to take a new watch from a showcase and do a scratch test on it.” A steel knife or screwdriver will scratch a mineral glass but not a sapphire.
Are scratch-resistant crystals new?
No. Synthetic sapphire was invented in the 19th century and first used for watch crystals in the 1960s. Now really all high-end watch brands use synthetic crystals in at least some or their models.
Are all scratch-resistant crystals made of synthetic sapphire?
No. Some mineral-glass crystals are also marketed as “scratch resistant.” These crystals have a hard coating that makes them less likely to get scratched.
What do the watch crystal terms "Lunette, Bombé, Chevé and Boule" mean?
All are French words that refer to the shape of the crystal. “Lunette” simply means round-like a full moon (lune means “moon” in French). Bombé, Chevé, and Boule all means concave, or dome-shaped. There are other words used to describe watch crystals’ shape. A “raised” crystal is flat on top but dome in the centre. “Shaped crystals” are any that are not circular. Rectangles, square and ovals being the most common.
What are "Anti-reflective" or "Glare-resistant" crystals?
This type of crystal has been coated on one side or both sides with a substance that makes it easier to read the dial of the watch in direct sunlight. One interesting feature of these crystals is that is has a distinctive tint to it.
How much do watch crystals cost to replace?
Consumers can expect to pay anything from R80 to R160 for a plexi glass to more that R600 for Synthetic sapphire one. (At Omega, Rolex and other top-end brands, for example, synthetic sapphire crystals range from R600-R1200. In general, the more expensive the watch the more you will pay for a crystal replacement.
FAQ – Automatic Watches
What is an automatic watch?
Is it the same as a hand wound watch?
No. Hand wound is a mechanical watch that the wearer winds by turning the crown by hand.
Why do they call it "Automatic"?
What is the difference between an automatic and a selfwinding watch?
Is that the same as a "perpetual" watch, (eg Rolex Oyster Perpetual)?
Correct. Rolex refers to its automatic watches as “perpetual.” Automatic, self-winding and perpetual all mean the same: the watch winds itself. (A perpetual Calendar, however, is something else.)
How does an automatic watch work?
The movement of the wrist and the body cause the rotor, a metal weight attached to a winding mechanism, to pivot freely on its staff in the centre of the movement. The rotor rotates back and forth in a circular motion at the slightest motion of the wrist. The rotor’s movement winds the mainspring, a flat coiled spring that powers mechanical watches.
Who invented the automatic watch?
The modern rotor system was developed and patented by Rolex and introduced into the Oyster line as the Oyster Perpetual in 1931. Emile Borer, Rolex’s technical chief at the time, is credited with inventing the modern rotor system. The person who first developed a rotor, however, was Abraham-Louis Perrelet(1729-1826), one of Switzerland’s greatest watchmakers. Perrelet is considered the father of the automatic watch. He introduced the concept in 1770 and was way ahead of his time since the invention was better suited to wristwatches. Perrelet lived in the pocket watch era and, because the watches did not move much in pockets, the rotor system did not perform so well. The rotor did not move around enough to wind the mainspring sufficiently. Abraham-Louis Breguet (1747-1823) improved “self-winding watches”, he called them “perpetuelles” (likely source of Rolex’s term). Other watchmaking greats of the 19th century advanced the concept. But it was not until wristwatches became popular after World War 1 and Rolex perfected its system that automatics came into their own.
Why do we see more automatic watches these days?
Like all mechanical watches, automatics lost favour during the Quartz Watch Revolution of the 1970’s. Electronic watches were the rage then and were far more accurate than mechanicals. In the mid-1980’s, however, as quartz watch production soared to hundreds of millions of pieces each year, some people, mostly watch collectors, began to appreciate the value of a fine mechanical watch. In the past 10 years, fine mechanical watches have staged a comeback on the world markets. Automatics have rebound as part of the mechanical counter-revolution.
Why are they so popular?
Many people appreciate the craft involved in making a mechanical automatic movement. They like the fact that this technology is hundreds of years old, involves many moving parts and yet keeps very accurate time. (Many automatics come with glass backs, which enable the wearer to view the action of the rotor and other moving parts.) They appreciate the human element involved in an automatic watch, that the movement is assembled by hand. Others like the fact that automatics run on so-called “clean” natural energy, wrist power and that there are no pollutive batteries to dispose of.
How accurate are they?
Mechanical technology, by definition, is inferior to the extreme accuracy of an electronic watch. Automatics are accurate enough for normal daily timekeeping. A normal automatic is accurate to within +30/ -5 seconds a day, depending on the quality of the movement.
Are they expensive?
They can be, but not necessarily. Automatics are available in every price range, starting with Swatch automatics.
How much motion does an automatic watch need to work properly?
A relatively active person’s normal arm and wrist motion will keep an automatic watch wound properly. People who are inactive (the elderly or patients confined to beds) may need to wind their watch to keep it powered.
Is it safe to wind an automatic watch?
Absolutely. Winding the watch will not hurt it at all. If you have not worn an automatic for a while, it is best to wind the stopped watch before putting it on. Ten to 15 turns of the crown is usually enough to start the mainspring winding. But, be aware that the barrel in an automatic movement does not have a hook so that you could feel any resistance when the mainspring is fully wound. Do not worry, you cannot over wind an automatic watch.
How long will an automatic go when it is not worn?
How often does an automatic need to be serviced?
Most companies recommend the watch be checked and relubricated every three to five years. If the wearer regularly subjects a water resistant automatic to water, the seals should be checked annually.