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Basic Picking and the binding defect
The flatland model highlights the basic
defect that enables
lock picking to
work. This
defect makes it possible to open a
lock by
lifting the
pins 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 the most.
3. Push that
pin up until you feel it set at the
sheer line.
4. Go to step 2.