Pressure Testing

Pressure Testing Your Watch

Watches have numerous entry points for possible water ingress. During the lifetime of a watch, the seals on these entry points can corrode. If any of these seals are removed to gain entry to the case or to replace a worn part, the seal may be broken in the process and will require a pressure test. At Timepiece Watch Repairs in Chester we can 'reseal' and pressure test your watch after a battery replacement or other watch repair. If the watch seals are too worn, we can usually replace them.

During everyday use your watch's rubber seals can dry out and start cracking, especially where your wristwatch is used in salty water or water containing chlorine. If the seals are in good condition, re-greasing your seals with the correct greases maintains their condition each time your watch is resealed. We 'pressure' test many different brands and types of water resistant watch at Timepiece Watch Repairs in Chester. We carry out pressure testing to confirm that your watch continues to be water resistant to the manufacturer’s original specification once a repair has been carried out to the watch case. A pressure test is normally required when a new battery is fitted or other repairs are carried out to the watch case, for example a new glass, pusher or winder. Each of these components play an important part in the water resistance of your watch.

A pressure test is usually either an air test or a water test. To carry out an air test, also known as a vacuum test, the watch case is placed in an air testing machine with a fine measuring needle resting on the watch glass. Then, air is removed from within the machine causing an air vacuum around your watch. The air pressure inside the watch will try to equalise with the air pressure outside the watch creating a very slight bend in the watch glass. The needle resting on the glass measures the amount of bend. After a minute the measurement should be checked to see if it has changed. If the measurement is now different, then some air has escaped from the watch signifying a leak. If the measurement remains the same, the watch is probably air tight. An air test is quick and doesn't use water. Unfortunately, watches with a thicker glass sometimes don't bend so no change will be measured and the test is inconclusive. If the watch glass is domed, the needle can sometimes move across the glass slightly causing an inaccurate measurement. Another problem with air testing is that no exact pressure is defined and only shows that a watch case is air tight but now how air tight. A water test involves placing the watch in an air pocket above some water inside a water testing machine. Air is pumped into the tank increasing the air pressure inside the tank and after a minute or so the watch is submerged in the water. The air inside the water tester is then released slowly. Like air testing, if any air has leaked into the watch before submersion, it will try to equalise with the lower pressure outside the watch. If this happens, it is visible as a constant stream of bubbles coming from the position of the leak. The important thing to point out is that air is escaping from the watch and not water entering it. If there is no stream of bubbles then the watch is air tight. This method is also superior to air testing in that the amount of air pumped into the machine can be altered to test for different water pressures e.g. 100 metres, 30 metres, 50 metres and so on. Water testing takes a little longer than an air test but is substantially more accurate and shows the exact position of any leak. This of course means that any necessary repairs will be completed faster and could cost less.

Our staff at Timepiece Watch Repairs in Chester use water testing for checking seals and can usually install a high quality battery and pressure test your watch to the correct specification in less than half an hour. At Timepiece Watch Repairs in Chester, we only use top quality silver oxide battery cells. Lesser quality batteries can sometimes leak and damage your watch movement, occasionally irreparably. Besides poor quality silver-oxide batteries, alkaline batteries, although appearing to be similar, don't normally last more than a few months and again, there's a high risk of them leaking when used inside your watch. All Timepiece staff are well trained and experienced and can replace a watch battery with the right type using the right method, and without damaging your case back, movement or battery clamp. We carry out a number of other watch repairs including watch servicing to most brands of watch. Visit your local Timepiece store to discuss your watch repair with one of our helpful technicians. We also stock a large range of quality watch brands in store.