This article is from the Locksmithing FAQ, by Joe "Spike" Ilacqua spike@indra.com and Henry Schaffer hes@ncsu.edu, major data collection effort by Scott Anguish sanguish@digifix.com with numerous contributions by others.
A "pick gun" is a manual or powered device that uses a vibrating
pin to try to bounce the pin tumblers so there are spaces at the
shear line so that the plug can rotate. Some kind of turning
pressure is also needed - either during or a split second after
the click. The MIT Guide has some discussion of this. Pick guns
are not a panacea, and aren't always effective although some
people find them to work extremely well. The net seems to feel
that these are no substitute for a little skill with a pick and
learning how locks work. The electrically powered ones are
considerably more expensive, and many question whether they are
worth the cost. Pick guns should not be used on wafer tumbler
locks as they will not pick the lock and can damage the wafers and
springs.
The following "ascii art" may make this easier to understand:
\ / <-- Spring, pushes pins down. \ |-| ------- | | ------- <-- Shear line, where the |_| plug meets the cylinder. |-| | | |_| ^ <-- Keyway | | Pick gun delivers sharp blow to bottom pin.
\ / \ |-| | | <-- Top pin thrown up by blow. |_| -------------------- <-- Shear line, where the plug meets the cylinder. |-| | | <-- Bottom pin stays in place. |_|
Thumb presses here, then releases with a snap. | v _______________________ / _____ | | / / \ | | | | | | | <--- Pins go here, where \ \-----/---------------|--------------- they will receive \_____/ \ / ^ the force of the \_/ | "click". ^ | | ^ Flatten needle with hammer, | | shorten height with file. Wrap around something | This part goes into like a broom handle. | the lock under the pins. | This part imparts force to the needle which imparts force to the pins.
Clothespin Clicker: ____________________________________ \ _ --------------| <-- Thin strip of metal placed -----------/-\___/ \_| in groove cut in top of -----\-/ \_/ | clothespin. /_______________/ ^ | Lower part shortened to make operation easier. Finger pulls up here, and then releases. Force is transfered to needle, and then pins.
____________________ __ / \ / \ | | / | | | | | | | | | \__ | | | Needle. This part \ __________ | | _______________ <-- transfers force to | / | | | pins. Hammer thin, | | \_| _/ and file down height. | | | | | | <-- Trigger. Forefinger pulls here, and | | | releases with a snap. | | \ | | | __ | | / \ | |\ || <-- Wrap around something \_\___/| like a broom handle. \___/
 
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