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Basic Picking and the binding defect
The flatland model
highlights the basic defect
that enables lock picking
. This defect
makes it possible to open a lock
s one at a time, and thus you don't need a key
to lift all the pins at the same time. The pins of a lock can be set one at a time. The first step
of the procedure
is to apply a sheer force
to the lock by pushing on the bottom plate
. This force causes one or more of the pins to be scissored between the top and bottom plate. The most common defect a in a lock is that only one pin will bind. Even though a pin is binding, it can be pushed up with a picking tool
. When the top of the key pin reaches the sheer line, the bottom plate will slide
slightly. If the pick is removed, the driver pin will be held up by the overlapping bottom plate, and the key pin will drop down to its initial position
. The slight movement
of the bottom plate causes a new pin to bind. The same procedure
can be used to set the new pin.
Thus, the procedure for one pin at a time picking a lock is to apply sheer force
, find the pin which is binding
the most, and push it up. When the top of the key pin
reaches the sheer line, the moving portion of the lock will give slightly, and driver pin
will be trapped
above the sheer line. This is called setting a pin.
Chapter 9 discusses the different defects
that cause pins to bind one at a time.
1. Apply a sheer force
2. Find the pin that is binding
3. Push that pin
up until you feel it set at the sheer line
4. Go to step 2.