Pressure Testing Your Watch
At Timepiece Watch Repairs in Bury we 'pressure' test many different types of water resistant watch. Pressure testing will confirm that your watch continues to be water resistant to its original specification once a case repair has been carried out. A pressure test is frequently required when a new battery is fitted or when other repairs are carried out to the case e.g. a new glass, pusher or winder. All these components play an important part in the resistancy of your watch to water. A sealed watch is manufactured with seals at each entry point on the watch case. These entry points include the glass (or crystal), the case back, buttons and pushers.
Other watches may however have different entry points. During the lifetime of a watch, the seals on it's entry points can begin to corrode. When any of these seals are removed to gain entry to the case or to replace a worn component, the watch seal may be broken and will require a pressure test. At Timepiece Watch Repairs in Bury we can 'reseal' and pressure test your watch after a battery replacement or other watch repair. Where the watch seals are too worn, we can normally replace them. Through everyday use your watch's rubber seals will become dry and start to crack, particularly where your wristwatch is used in salty water or water containing chlorine. If they are in good condition, applying the correct greases to your watch seals maintains their condition each time your watch is resealed.
Once your timepiece has been sealed it requires a pressure test. The test is normally either an 'air test' or a 'water test'. To carry out an air test (also known as a vacuum test), your watch is placed on a podium in an air testing machine with a 'needle' resting on the watch glass. When air is removed from within the machine, an air vacuum is created around your watch. The air pressure inside the watch will attempt to equalise with the air pressure outside the watch making the watch glass bend very slightly outwards. The needle on the glass measures this bend. After a minute the measurement should be checked for changes. If the measurement is different, then air has escaped from the watch signifying a leak. If it remains the same the watch is probably air tight. This kind of test is quick and uses no water. Unfortunately, watches with thick glass sometimes won't bend and no change will be apparent. If your glass is domed, the needle can move across the glass slightly causing an inaccurate measurement.
Another disadvantage of an air test is that no specific pressure is defined and signifies only that a watch case is air tight to a degree. Water testing involves placing the case in a pocket of air above water within a water testing machine. The air pressure inside the tank is then increased and after a minute or so the watch is submerged in the water. The air pressure inside the machine is then released slowly. As with air testing, if air has leaked into the watch before it is submerged it will try to equalise with the lower pressure outside the watch. When this happens, it is clearly visible as a persistent stream of bubbles coming from the location of the broken seal. The important thing to note is that air is escaping from the case and not water entering it. If there is no constant stream of bubbles then the watch is air tight. It is also superior to an air test in that the air pressure in the machine can be changed to test for different water pressures e.g. 100 metres, 30 metres and so on. Water testing is a longer procedure than an air test but is a lot more accurate and shows the exact position of any leak. This means any required repairs are completed faster and may cost less.
Our technicians at Timepiece Watch Repairs in Bury use a water tester for testing seals and we can usually fit a new high quality battery and pressure test your watch to the correct specification in under half an hour. At Timepiece Watch Repairs in Bury, we use high quality silver oxide batteries. Poor quality batteries sometimes leak, and can damage your watch movement irreparably. Alkaline batteries, although similar in appearance, won't normally last much more than a few months and there's a high risk of them leaking when used in a watch. Timepiece staff are well trained and experienced and will replace your watch battery with the correct type using the correct method, without damaging the case back, movement or battery clamp.
We carry out many other watch repairs including servicing to the majority of watches. Please call in to your local Timepiece store and speak to one of our helpful technicians for advice on your watch repair. We also stock a large range of quality watches in store.