Fit A Battery To A Watch

[Mark]

The principles of best practice for replacing a battery in a water resistant (or water proof) watch and performing a pressure test using a calypso pressure testing tool for watches.Fitting a watch battery

A simple task? Well, it can be. But there is a right and a wrong way to do it.

Fitting a new battery into a watch is not rocket science but there are some things that can go wrong.

The pitfalls

• The first thing to observe after removing the watch back is what way up the existing battery is.

  As you may or may not know - a battery has a positive and a negative terminal. With most watches the negative side is facing downwards. But this is not always the case. Some watches have the battery in upside down (negative up) by design.

  It is important to realise that putting the battery in the wrong way round will not only prevent the watch from working, but will also short the battery out and cause the life (power) in the battery to drain.

• The watch circuit is very sensitive. One touch in the wrong place can render the circuit useless.

  The circuit in simplest terms is made up of two parts - the main circuit board and the coil. Now in some cases these are two separate parts and in other cases these are one piece.

  The coil is many meters of copper wire, coated in wax and wrapped around an iron core which creates a magnetic field when power passes through it. You will observe this part to be orange (copper) in colour.

  As this copper wire is so thin it can be damage by the slightest of touch and so it is very important to be extremely careful when you replace the battery to keep clear of the coil.

• Often there is a plastic isolator (shield) under the battery (and tucked away under the negative contact). This is easy to miss when you remove the battery and can fall away. Fitting a battery without the isolator in place will cause the battery to short.

  It should be noted that not all quartz movements have isolators so be careful to observe this when removing the old battery so that you can restore it back to the way it was.

Best Practices

Before removing the watch back - make sure all dirt and debris are removed and cleaned away from around the watch back. This will help prevent dirt contaminating the movement.

If the watch is a water resistant model then you should have a silicon grease applicator to clean and re-lubricate the back gasket before re-assembly. See this being performed in the video.

If the watch is a water resistant model then it is best practice to remove the winding crown and lubricate the 'o' ring inside the crown as seen in the video.

Use top quality batteries. They are not expensive and so it does not make sense to use the cheap brands. I recommend Renata.

Use the best tools you can afford. Using quality tools will reduce the risk of damage. Many watchmakers will insist on Bergeon or Horotec.

Use the correct watch back opener for the type of case. It would be a shame to cause damage to a watch back - but even worse to cause injury to your hand.

Please watch the video for further information.

If you have any questions please comment.

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