Keys

Locks

There are many different kinds of locks. Most of the locks that you'll play with on a day-to-day basis are pin tumbler locks, primarily of two brand names:

• Schlage (slightly sturdier, more versatile)
• Kwikset (slightly less sturdy, made of sand)

The inside of a typical pin tumbler lock, the first animation below shows how the pins are set to enable the cylinder to turn and release the latch/deadbolt.

• 

  Front View, normal operation

• 

  Side View, normal operation

• 

  Master Pinning (for master and change keys)

Mastering

You can also set pins on top of one another so that multiple keys can successfully turn the cylinder, using a "master" key and a "change" key. The idea is that several cylinders will be keyed to the "master" and each cylinder will also be keyed to its own unique "change" key.

Educational Resources

• Cylinder Locks on Wikipedia
• Lockpicking slides and links by TOOOL (The Open Organisation of Lockpickers)

Law

• In California, it is lawful to duplicate existent keys. Further, a "Locksmith" is defined as a person who engages "in the business of rekeying..." etc, "for any consideration or compensation whatsoever" ('consideration' meaning benefit of a contract i.e. not a gift).
  • Locksmith Act (index) of the Business and Professions Code.
  • SECTION 6980 of the Business and Professions Code:

(j) "Locksmith" means any person who, for any consideration or
compensation whatsoever, engages, directly or indirectly and as a
primary or secondary object, in the business of rekeying, installing,
repairing, opening, modifying locks, or who originates keys for
locks, including, but not limited to, electronic cloning of
transponder keys and any other electronic programming of automotive
keys and electronic operating devices, such as key fobs, door and
ignition key devices, and successive electronic and other
high-security key technology. A "locksmith" does not mean a person
whose activities are limited to making a duplicate key from an
existing key.

• In California, it is lawful to possess lock picks (i.e. circumvention tools) by statue, the state must prove criminal intent.
  • Burglarious And Larcenous Instruments And Deadly Weapons Section 466-469 of the California Penal Code

§ 466.  Every person having upon him or her in his or her possession a
picklock, crow, keybit, crowbar, screwdriver, vise grip pliers,
water-pump pliers, slidehammer, slim jim, tension bar, lock pick gun,
tubular lock pick, bump key, floor-safe door puller, master key,
ceramic or porcelain spark plug chips or pieces, or other instrument
or tool with intent feloniously to break or enter into any building,
railroad car, aircraft, or vessel, trailer coach, or vehicle as
defined in the Vehicle Code, or who shall knowingly make or alter, or
shall attempt to make or alter, any key or other instrument named
above so that the same will fit or open the lock of a building,
railroad car, aircraft, vessel, trailer coach, or vehicle as defined
in the Vehicle Code, without being requested to do so by some person
having the right to open the same, or who shall make, alter, or
repair any instrument or thing, knowing or having reason to believe
that it is intended to be used in committing a misdemeanor or felony,
is guilty of a misdemeanor. Any of the structures mentioned in
Section 459 shall be deemed to be a building within the meaning of
this section.
§ 466.3.  (a) Whoever possesses a key, tool, instrument, explosive, or
device, or a drawing, print, or mold of a key, tool, instrument,
explosive, or device, designed to open, break into, tamper with, or
damage a coin-operated machine as defined in subdivision (b), with
intent to commit a theft from such machine, is punishable by
imprisonment in the county jail for not more than one year, or by
fine of not more than one thousand dollars ($1,000), or by both.