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Salient. Victoria University Student Newspaper. Volume 36, Number 10. 23rd May 1973

Locks and Shackles

page 16

Locks and Shackles

Photo of a men's room door

Member of Women's Liberation Battalion uses Karate, enters and liberates locked men's room. However this technique damages doors and locks.

Photo of someone locked out of their van

Army Service Corp driver ponders on how to enter van, the keys for which were stolen by the Victoria University Viet Cong. Regimental locksmiths quickly managed to open door and start ignition with simple home-made tools.

Photo of a chastity belt

War Department Women's Auxilliary standard item of equipment 1914 — 1973 "Belt, webbing, chastity, locked, with key, 1914 pattern." This sort of problem may have been frustrating in the past but with the skills described here the enterprising student and soldier will find such obstacles insignificant.

The Rape Of The Lock

""I've tried to unlock it but alas no avail, the cunning old bastard has fitted a Yale, Hey Nonny nonny Fitted a Yale Fitted a Yale

The cunning old bastard has fitted a Yale" — from an olde English Folk song — circa 1960.

Most people in our property owning democracy have at some time suffered the inconvenience of being locked out of their cars, offices, houses, or sale deposit boxes etc through the misfortune of having lost or mislaid the key. Or one might have been in some strife over an intervening chastity belt, and unlike the page boy in the song unable to "gladly unlock it with a duplicate key".

Here, for the convenience of impoverished students unable to afford either replacement keys or the time to acquire them, is some information on overcoming this annoying predicament.

For more complex locks, combination locks etc, similar and different techniques may be neccessary, and for most students not possessing the required skills it would be neccessary to acquire the services of the Regimental locksmiths, although competence in these matters is restricted only by the limits to one's technical skill, manipulative dexterity and imagination.

It must be mentioned that possession of some of the tools described here might be viewed, quite reasonably, with some dismay, perhaps even hostility, by the Police Department, for unless one has a legitimate use for such devices it is the prerogative of the Police to suppose that such tools may be intended for criminal purposes. It was, therefore, with some reservations that we considered including this material from the American free press, but because students are as citizens socially committed to responsible and legal behaviour we present this information. However, the time and skills involved in acquiring competence as an amateur locksmith are no doubt beyond the patience, ability and, in some ways, the intelligence of most students.

Ward Locks

The first mass produced padlocks were the Warded Padlocks. In this type of padlock there are obstructions of 'wards' that prevent the turning of the key blank. If the key blank is notched so that it bypasses the wards; if is free to turn and operate the release spring. When this spring is released, the Shackle jumps up, being pushed by the Shackle Spring.

The adjacent diagrams show how the cut key spreads the release spring as it turns.

In this course the pass key is used for enabling the beginner to test a padlock so that one can tell if the padlock is of the warded type. Therefore the next step is to convert the key you just made into a pass key. Place the key in a vise and file away the metal where indicated in the following illustration. The pass key can be used to test padlocks with the following keyways to find out if they are of the warded type.

Engineering diagram

Drawing of a key

File Away Shaded Section

Please refer back to the open diagrams of a warded padlock in this lesson.

In looking at the diagrams, can you see how a key with just one long cut on each side of the blade would be able to open the padlock? Can you see how such a key, with most of the metal cut away would not engage any of the wards? Here's a diagram of it.

Engineering diagram

Drawing of a key

Such a key is called 'Pass Key' or 'Skeleton Key,'. Most locksmiths carry such keys for emergency openings, or for testing a padlock to see whether it is a warded lock or not.

Warded locks are usually the cheaper made locks. Most heavy duty or security padlocks are of the pin and tumbler variety next described. You can usually tell if the lock is a pin and tumbler variety by seeing whether the key hole is round and has a pin in it.

Pin & Tumbler — Common Locks

The plug in a pin tumbler cylinder will not turn in the shell unless the correct key is inserted. To understand why, let us look into a cylinder. In the following cross-section view we see a section of a key in the key way. The key is supporting two small pins while a small coil spring is pressing down upon them from the top. In this position the plug cannot turn because the lower pin is half-way between the plug and the shell.

In the next illustration, however, the section of the key is much shorter & now it is the upper pin that is preventing the plug from turning.

But the following illustration shows that the key has raised the pins just high enough so that the lower pin can separate from the upper pin and permit the plug to turn.

Drawing of locks

The following side view of the lock without the key inserted shows how all of the upper pins have been pushed into the plug, thereby locking it.

Engineering diagram

This illustration shows how the correct key "lines up" the lower pins so that all of the upper and lower pins meet at the top of the plug, which is known as the shear line.

Engineering diagram

Here we see how all of the lower pins are locking the plug to the shell when a plain key is inserted in the lock.

Key in a lock diagram

page 17

Lock Picking

Lock picking is a necessary skill in servicing locks as well as having freedom of access. Many locks cannot be taken apart that easy and it is best to pick them in order to open. Often the quickest way to turn the plug is by picking. But picking is not a universal answer to opening all locks. Contrary to the movies or other such educational tools there are many locks that cannot be picked and often it isn't just a flick of the wrist with a small tool that will open the lock.

Picking skill is very much a matter of practice and patience. But one must be aware of the fundamentals first. Here we will give Some basic info, on picking the pin tumbler and the disc tumbler locks.

Warning Many of the Steps May Seem Very Simple to you but it is Essential that you Follow them to the Letter and Skip None.

Drawing of lock picking

Feel Method — 1

Review the principles of the pin tumbler lock Be sure that you understand it before proceeding.

A lock pick is nothing more than a thin, stiff piece of hardened steel that will enter the key way of a lock and manipulate the tumblers. At the bottom right you will find the most common picks used depicted. Examine them. The irregular shaped ends are formed to enable the locksmith to raise and lower the tumblers in the lock. Also described and drawn is a "turning wrench" a short piece of steel with short lugs bent at an angle. It is used in the key way of the lock to put a turning pressure on the plug in the same way that a key is used.

To practice obtain a pin tumbler cylinder of a normal lock. Remove all the pins and springs as well as the plug retainer plate and plug. Place the cylinder in a vise so that you can conveniently insert the turning wrench and pick in the key way. Select the pick that resembles the one in the illustration. Apply a turning pressure on the plug with the wrench and try to raise the bottom pin up to the shear line. See Drawing. Keep Practising.

Drawing of lock picking

You will notice that the harder you turn the wrench, the more difficult it is to raise the pin. However, you will also note that when the bottom pin has reached the shear line, the plug will turn immediately.

Practice this little exercise 25 times using less and less pressure each time on the turning wrench. You will soon get the "feel" of a pin tumbler when it reaches the shear line under the lightest possible turning pressure.

Shear line diagram

Diagram of lock picking

Now reverse the position of the wrench by placing it at the top of the key way as shown in the illustration, practice raising the pin to the shear line with the pick with the wrench in the shown position.

The reason for these two positions is a very simple one. In some plugs the turning wrench fits very snugly into the key way. In fact it "crowds" the space and this prevents the pick from working freely. In working both positions you will be able to tell which is most practical and comfortable.

When picking under normal conditions one should start either at the front pin or the rear and work your way forward or backward in order. One should use the turning wrench to keep the pins that have been raised in place. In some cases the pick can do this also. Some locks are machined such that they will stick when you raise the pins. This depends on the quality of the lock.

Cartoon of a man locked-in

Raking Method — II

Some locksmiths use what is commonly known as the "raking method". Although it is not as scientific or as sure as the feel methods, it is often used as a short cut. A locksmith tries this method first on the cylinder, if it works you don't have to bother with the feel method.

In the adjacent drawing you see a rake pick, being worked in a cylinder. The idea is to run the rake quickly under the bottom pins. This action often causes the bottom pins to bounce up to the shear line and hang there as the plug is turned out of alignment with the upper pin holes. The time that it takes to open a lock this way depends on the speed of the wrist as one manipulates the rake in and out.

Take the practice cylinder with at least three of the pins in place and practice. The raking method can become quite a knack. Practice is the key to this method, but one must remember that security locks and the better made locks with mushroom pins or well machined locks won't open with this method. Jiggling is often the term used instead of the raking method.

Diagram of a lock

Gun Picks — III

For an understanding of the way a gun pick works refer to the game of billiards. No doubt you have seen how when the cue ball hits the other ball they immediately separate as shown in the drawing. The same action occurs when the pick of the gun hits a bottom pin. The upper pin is driven upward as the two parts separate.

The function of the gun pick is to strike all the bottom pins in the cylinder at once and bounce the upper pins into their chambers, while the lower pins remain in the lower chambers. When this happens there are no pins blocking the shear line and the plug is free to turn.

In theory the lock should open on the first "bounce". But there are various other factors to consider. Pins vary in length, springs vary in pressure and strength, & often the designs of key ways make it difficult to hold the needle in a position where all of the pins can be struck equally as hard at the same time. Many locks are designed with high ridges, that is short and long pins following to prevent picking. They can be picked but not with a gun pick.

Electric vibrator picks are the most modern method used for picking locks. The vibrator acts like the gun pick but the needle is actuated electrically to bounce the cylinders apart. It is almost impossible to make your own tool, and equally as hard to get one however.

Diagram of a door lock

Engineering diagram

Disc Tumbler Picking — IV

Disc tumber locks are a cheap substitute for pin tumblers and are easily picked when the pin tumblers are mastered. The diamond shaped pick is the one most commonly used for these locks. See drawings below for the principle of the lock.

In drawing 1 the lock is locked. The spring loaded discs tumbers are pushed into shell slots. In drawing 2 the key forces the withdrawal of the discs. In drawing 3 the plug rotates.

Drawing of locks

How to make Picks

To make the picks illustrated here you should have about 6 feet of spring steel, or ordinary steel wire (flat) 5/16" wide and .020" thick. This can be obtained from any locksmith supply jobber. A warding file, 3-corner saw file, and a coarse round file are also needed A small amount of glue, rubber cement, fine emery cloth and bench grinder complete the list.

Break off a piece of wire equal to the length of pick you want. Polish it on one side with the emery cloth. Keep fingers off this side afterwards. Cut one pattern and glue it to the polished side. Using your grinder remove the excess metal around the outline of the pick to within 1/16" of the line. Avoid burning the steel by dipping it in water often.

Hand file the rest of the steel away until the proper pattern and size is obtained. Polish the finished steel with a slightly oiled emery cloth. The picks should be tempered, but retain some flexibility.

Diagram on how to make locks