Watch parts – what are they and what do they do?

Chronograph pushers

When you are entering the world of watch collecting for the first time, you will come across all kinds of strange terms. Let WRUK demystify some of them for you:

Watch Parts and What They Do

Hands

Watch hands
Some watches have more than three hands!

Okay, we all know how to tell the time, and we are all familiar with hour, minute and second hands. Some wristwatches have more than the usual three hands. Chronograph watches are the most common variant you will come across. These are stopwatches and usually have at least one extra dial on the face, with its own hand. “Real” chronographs (as opposed to fashion watches) have the central (or “sweep”) second hand fixed unless the stopwatch is activated, with running seconds in a sub-dial. Many new collectors do not realise this and leave the chronograph running permanently to see the big second hand moving all the time. This is not a good idea; it will wear down the battery faster, or cause wear to a mechanical watch.

Seiko-Kinetic-GMT
A GMT watch has two independent hour hands

Another multi-handed watch is the GMT. These keep track of multiple time zones, with one hour hand usually fixed to Greenwich Mean Time (or UTC – Universal Time Code) and the ‘normal’ hour hand set at the local time. They were designed for pilots, who need to track multiple time zones simultaneously.

Case

Empty watch case
An empty watch case with spring bars fitted

The case is the bit of the watch that holds all of the internal workings. It is usually detachable from the strap. Cases come in various sizes, and when you see a measurement (such as 39mm or 42mm), it is usually taken across the case, between 3 O’clock and 9 O’clock, but excluding the winding crown. Take care when buying vintage watches, as tastes have changed and modern watches are usually some 10mm bigger than pieces from the 1960s.

Cases are generally made of metal, but some come in plastic or ceramic. Case backs come in screw and pop fittings, and if you need to take the back off your timepiece, you will need a special tool. Let a professional change your battery if you are unsure!

Complications

Complications are anything on a wristwatch other than the time: the day, date, sub-dials, power reserve features, etc. Some watches show the month or even the phase of the moon.

Dials and Sub-dials

Subdials
A watch with three sub-dials

The dial is the circular bit with numbers or markers on it. Sub-dials are smaller dials within the main one, most often to show elapsed time from the stopwatch function or, occasionally, whether the time shown on the main dial is AM or PM.

Bezel

Some watches have a bezel around the dial. This often rotates. If the numbers shown on it are 0-60, then it is most likely a diving bezel. You point the triangle at the top to the minute hand and can then work out how much time has passed. These bezels only turn one way so divers can only overestimate the time they have been in the water.

Dive watch bezel

1-24 dials are usually found in GMT watches and allow te watch to show two times at once. The GMT hand traverses the face once every 24 hours. Other bezels are purely decoative.

Bracelet or Strap

Watches usually come on bracelets or straps. These are held on with spring bars – tiny spring-loaded roads that can be removed with a special tool. Some watches have ‘lug holes’ – tiny holes on the outside of the case where the strap fits, and others have gaps in the ‘end links’ (metal pieces at the end of the bracelet) in order for the strap to be removed with a special tool.

Wristwatch bracelets are usually metal and have fixed and removable links. A jeweller (or you, with the right tools) can remove some links to make it fit. The removable links usually have arrows on the back. Many watches can also be adjusted at the clasp, by adjusting a little push pin.

NATO straps
NATO Straps

Straps come in the traditional two-piece design and also in the military NATO or Zulu style. These kind of straps are a single piece of leather or nylon and thread underneath the spring bars, so you do not need to use a tool to switch the strap. Swapping NATOs is a quick way to change the look of a watch.

Straps are most often secured by a “tang buckle” – which is like a belt buckle. Increasingly, “deployant clasps” are being used, which are similar to the clasps on watch bracelets and which do not leave part of the strap poking through.

Movement

Quartz movment
A typical quartz watch movement

The movement is the part of the watch that keeps time. Mechanical movements work by the controlled unwinding of a mainspring and usually tick smoothly between five and eight times per second. Quartz movements tick once per second and are usually more accurate. Enthusiasts usually say they prefer mechanical timepieces.

Rotor

Automatic watch movement
An automatic watch movement

Mechanical watches can be hand-wound, or automatic. Automatic watches are wound while they are being worn. The part that makes this happen is called the rotor. This is an offset weight inside the watch. If you do not wear an automatic watch for a couple of days, then it will stop. Swirling it, like a glass of whisky, gets it running again. Some people invest in watch winders, which keep the watch moving, so it stays wound, but opinion is divided over whether this does more harm than good to the delicate movement.

Crown

The bit you wind the watch with, and set the time, is called the crown. Many divers watches have a ‘screw down crown’  which has to be unwound anticlockwise before you can set the time or wind the watch. This is to keep the watch water-tight. Make sure to screw the crown back in once you have set the time or else water can get in and fog up the watch.

Rolex watch crown
The crown on a Rolex watch

Crowns usually pull out to two or three positions. The first position, when it is flush against the watch or when a screw down crown has been unwound is for winding the watch. 20-30 clockwise rotations are enough to charge up most timepieces. Be careful not to overwind a mechanical watch as this can break it. Automatic watches have a clutch to prevent overwinding.

The second position most often changes the date and/or day – depending which way you turn the crown. The third is for setting the time. If you change the date on a watch, try not to do so between 10 pm and 2 am as this can damage the date change mechanism. If your watch changes the date at midday instead of midnight, simply wind it forward 12 hours and reset the date!

Pushers

Chronograph pushers
Chronograph pushers

Pushers are the parts of a chronograph that start and stop the stopwatch element. The one at two O’clock usually starts and pauses the timer, and the one at 4 O’clock resets it. Make sure a mechanical chronograph is stopped before resetting it or you may damage the watch.

We hope this primer helps you identify the main parts of your watch, let us know if we have missed anything!

Author: Mike Richmond

Usually found skulking around eBay or the International Watch League forum, Mike writes for a living and spends what little money he makes building up his collection of timepieces.

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