How Lock Picking Works - IELTS Reading Answers & Explanations

You should spend about 20 minutes on Questions 15–27, which are based on Reading Passage 2.

How Lock Picking Works

Section A

Lock picking is an essential skill for locksmiths because it lets them get past a lock without destroying it. When you lock yourself out of your house or lose your key, a locksmith can let you back in very easily.

Lock-picking skills are not particularly common among burglars, mainly because there are so many other, simpler ways of breaking into a house (throwing a brick through a back window, for example). For the most part, only intruders who need to cover their tracks, such as spies and detectives, will bother to pick a lock.

Simply understanding the principles of lock picking may change your whole attitude toward locks and keys. Lock picking clearly demonstrates that normal locks are not infallible devices. They provide a level of security that can be breached with minimal effort. With the right tools, a determined intruder can break into almost anything.

Section B

Locksmiths define lock-picking as the manipulation of a lock's components to open a lock without a key. To understand lock-picking, then, you first have to know how locks and keys work.

Think about the normal deadbolt lock you might find on a front door. In this sort of lock, a movable bolt or latch is embedded in the door so it can be extended out to the side. This bolt is lined up with a notch in the frame. When you turn the lock, the bolt extends into the notch in the frame, so the door can't move. When you retract the bolt, the door moves freely. The lock's only job is to make it simple for someone with a key to move the bolt but difficult for someone without a key to move it.

Section C

The most widely-used lock design is the cylinder lock. In this kind, the key turns a cylinder in the middle of the lock, which turns the attached mechanism. When the cylinder is turned one way, the mechanism pulls in on the bolt and the door can open. When the cylinder turns the other way, the mechanism releases the bolt so the door cannot open.

One of the most common cylinder locks is the pin design. Its main components are the housing (the outer part of the lock which does not move), the central cylinder, and several vertical shafts that run down from the housing into the cylinder. Inside these shafts are pairs of metal pins of varying length, held in position by small springs.

Without the key, the pins are partly in the housing and partly in the cylinder, so that the mechanism cannot turn and the lock, therefore, cannot open. When you put the correct key into the cylinder, the notches in the key push each pair of pins up just enough so that the top pin is completely in the housing and the bottom pin is entirely in the cylinder. It now turns freely, and you can open the lock.

Section D

To pick a pin lock, you simply move each pin pair into the correct position, one by one. There are two main tools used in the picking process.

Picks: long, thin pieces of metal that curve up at the end (like a dentist's pick).

A tension wrench: the simplest sort of tension wrench is a thin screwdriver.

The first step in picking a lock is to insert the tension wrench into the keyhole and turn it in the same direction that you would turn the key. This turns the cylinder so that it is slightly offset from the housing around it, creating a slight ledge in the pin shafts.

While applying pressure on the cylinder, you slide the pick into the keyhole and begin lifting the pins. The object is to lift each pin pair up to the level at which the top pin moves completely into the housing, as if pushed by the correct key. When you do this while applying pressure with the tension wrench, you feel or hear a slight click when the pin falls into position. This is the sound of the upper pin falling into place on the ledge in the shaft. The ledge keeps the upper pin wedged in the housing, so it won't fall back down into the cylinder. In this way, you move each pin pair into the correct position until all the upper pins are pushed completely into the housing and all the lower pins rest inside the cylinder. At this point, the cylinder rotates freely and you can open the lock.

Section E

You'll find pin locks everywhere, from houses to padlocks. They are so popular because they are relatively inexpensive but offer moderate security.

Another common type of cylinder lock is the wafer lock. These work the same basic way as pin locks, but they have flat, thin pieces of metal called wafers rather than pins. You pick the wafers exactly the same way you pick pins – in fact, it is a little bit easier to pick wafer locks because the keyhole is wider. Despite giving relatively low security, these locks are found in most cars.

Tubular locks provide superior protection to pin and wafer locks, but they are also more expensive. Instead of one row of pins, tubular locks have pins positioned all the way around the circumference of the cylinder. This makes them much harder to pick. Conventional lock-picking techniques don't usually work on this type of lock, which is why they are often found on vending machines.