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in general steep angles give you better feedback about the pins. Unfortunately, the steep
angles make it harder to move the pick in the lock. A tip that has a shallow front angle and
a steep back angle works well for Yale locks.
The half round tip works well in disk tumbler locks. See section 9.13. The full diamond
and full round tips are useful for locks that have pins at the top and bottom of the keyway.
The rake tip is designed for picking pins one by one. It can also be used to rake over
the pins, but the pressure can only be applied as the pick is withdrawn. The rake tip allows
you to carefully feel each pin and apply varying amounts ofpressure. Some rake tips are at
or dented on the top to makes it easier to align the pick on the pin. The primary bene t
of picking pins one at a time is that you avoid scratching the pins. Scrubbing scratches the
tips of the pins and the keyway, and it spreads metal dust throughout the lock. If you want
to avoid leaving traces, you must avoid scrubbing.
The snake tip can be used for scrubbing or picking. When scrubbing, the multiple bumps
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generate more action than a regular pick. The snake tip is particularly good at opening ve
pin household locks. When a snake tip is used for picking, it can set two or three pins at
once. Basically, the snake pick acts like a segment of a key which can be adjusted by lifting
and lowering the tip, by tilting it back and forth, and by using either to top or bottom of
the tip. You should use moderate to heavy torque with a snake pick to allow several pins to
bind at the same time. This style of picking is faster than using a rake and it leaves as little
evidence.
A.2 Street cleaner bristles
The spring steel bristles used on street cleaners make excellent tools for lock picking. The
bristles have the right thickness and width, and they are easy to grind into the desired shape.
The resulting tools are springy and strong. Section A.3 describes how to make tools that
are less springy.
The rst step in making tools is to sand o any rust on the bristles. Course grit sand
paper works ne as does a steel wool cleaning pad (not copper wool). If the edges or tip of
the bristle are worn down, use a le to make them square.
A torque wrench has a head and a handle as shown in gure A.2. The head is usually
1/2 to 3/4 of an inch long and the handle varies from 2 to 4 inches long. The head and the
handle are separated by a bend that is about 80 degrees. The head must be long enough
to reach over any protrusions (such as a grip-proof collar) and rmly engage the plug. A
long handle allows delicate control over the torque, but if it is too long, it will bump against
the doorframe. The handle, head and bend angle can be made quite small if you want to
make tools that are easy to conceal (e.g., in a pen, ashlight, or belt buckle). Some torque
wrenches have a 90 degree twist in the handle. The twist makes it easy to control the torque
by controlling how far the handle has been de ected from its rest position. The handle acts
as a spring which sets the torque. The disadvantage of this method of setting the torque is
that you get less feedback about the rotation of the plug. To pick di cult locks you will
need to learn how to apply a steady torque via a sti handled torque wrench.
The width of the head of a torque wrench determines how well it will t the keyway.
Locks with narrow keyways (e.g., desk locks) need torque wrenches with narrow heads.
Before bending the bristle, le the head to the desired width. A general purpose wrench can
be made by narrowing the tip (about 1/4 inch) ofthe head. The tip ts small keyways while
the rest of the head is wide enough to grab a normal keyway.
The hard part of making a torque wrench is bending the bristle without cracking it. To
make the 90 degree handle twist, clamp the head of the bristle (about one inch) in a vise
and use pliers to grasp the bristle about 3/8 of an inch above the vise. You can use another
pair of pliers instead of a vise. Apply a 45 degree twist. Try to keep the axis of the twist
lined up with the axis of the bristle. Nowmove the pliers back another 3/8 inch and apply
the remaining 45 degrees. You will need to twist the bristle more than 90 degrees in order
to set a permanent 90 degree twist.
To make the 80 degree head bend, lift the bristle out of the vise by about 1/4 inch (so
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Figure A.1: Selection of pick shapes
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3/4 inch is still in the vise). Place the shank of a screw driver against the bristle and bend
the spring steel around it about 90 degrees. This should set a permanent 80 degree bend in
the metal. Try to keep the axis of the bend perpendicular to the handle. The screwdriver
shank ensures that the radius of curvature will not be too small. Any rounded object will
work (e.g., drill bit, needle nose pliers, or a pen cap). If you have trouble with this method,
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