A key cutting machine is used to make duplicate keys. It works by tracing the shape of the original key, either with a computerized system or strictly by comparison when held against the original key. The high-speed carving blade of the key cutting machine then makes a copy of the original key’s shape onto an uncarved key.

Typically, key cutting machines are found at home improvement or hardware stores. There are seven types of key cutting machines: semi-automatic, automatic, code key, flat steel/bit key, laser key, manual key, and tubular key. Each machine creates duplicates of specific types of keys. The cost of a key cutting machine generally ranges from 350 to 10,000 US dollars (USD).

A semi-automatic key cutting machine does most of the work by itself. The operator loads the original key into one vice grip while the duplicate key is placed in another area. A micrometer traces the shape of the original key while cutting the duplicate key with a high-speed cobalt steel blade. Once the duplicate key is created with a semi-automatic key cutting machine, a high-speed wire brush ensures no metal spurs are left behind. The machine requires adjustment from time to time, and the final product must be carefully compared to the original to ensure accuracy.

Automatic key cutting machines require little operation by the user. The operator simply places the keys into the machine. A micrometer traces the key twice to get exact measurements, while titanium blades cut the blank key. A deburring brush removes any metallic flaws. An automatic key cutting machine can complete a duplicate key in twenty seconds.

Many hotels use specially coded key cards, and a code key cutting machine is used to make duplicates. In a code key cutting machine, the original key card is placed into the machine and the operator adjusts the machine to match up with the notches on the card. When this task is complete, the original key is removed and a blank card is inserted. The machine cuts the notches as specified and the duplicate key card is finished in seconds.

Duplicating a skeleton key requires a bit key cutting machine. A bit key cutting machine measures the depth of the key’s end, or bit, and then cuts a duplicate key to match.

A laser key cutting machine works the same way as an automatic key cutting machine, except that lasers do the cutting instead of a blade. This allows dimples to be placed in the key’s surface, which is necessary for many of today’s higher security key entry systems.

A manual key cutting machine is the least accurate of all key cutting machines. It clamps the original key and the duplicate key together, then passes a blade over the original key while cutting the duplicate key below.

Tubular key cutting machines are used when the original key has a tubular shape. Some lawn mower and snow blower engines use these types of keys. The tubular key cutting machine traces the shape of the key and creates a duplicate pattern of notches in the end of the tube.