- A duplicator copies wear. A code machine cuts to the manufacturer's specification.
- Deburr every key. A ragged edge shaves brass into the cylinder.
- Cut and measure a known test key daily. Drift is invisible until keys start failing.
- A dull cutter rounds the bottom of a cut and sits the pin high.
Duplicators
A duplicator holds the original and the blank in paired vices. A stylus traces the original while a cutting wheel mirrors the movement onto the blank. Speed is the whole advantage. Ten seconds and no information about the lock is needed.
Accuracy depends on the stylus and cutter being exactly aligned and exactly the same diameter. That alignment drifts as the cutter wears, so a duplicator needs checking regularly against a calibration key and adjusting when it drifts.
Deburr every key. A cut leaves a sharp ragged edge that will drag on the pins, shave brass into the cylinder and give a key that feels rough and works badly. A wire wheel pass takes two seconds and is the difference between a good key and an acceptable one.
Code machines
A code machine cuts to a depth and space specification rather than to a physical original. You enter or dial in the code, the machine positions the blank precisely at each space, and the cutter descends to a defined depth.
Because it works to the manufacturer's own chart, a code cut key is a factory specification key. It works in every cylinder on the system rather than just the one worn cylinder it was copied from, and it can be produced with no original key present at all.
Modern computerised machines hold thousands of depth and space charts and can cut laser track automotive keys, dimple keys and tubular keys as well as flat steel. They are the largest single equipment investment a new locksmith makes and the one that most expands what jobs can be accepted.
Calibration and quality control
Cut a test key on a known code at the start of a working day and measure it. A micrometer or a depth gauge tells you in thirty seconds whether the machine has drifted. Doing this daily is the difference between one bad key and a month of them.
Watch the cutter. A dull wheel tears rather than cuts, leaving a rounded cut bottom that sits the pin slightly high. That produces the classic works in one lock but not another symptom on a keyed alike system.
Keep a record for master key systems. When a customer reports a key failure and you know the machine was in calibration on that day, you can look at the lock rather than at your own work.
Common Questions
Why does a copy from one shop work and another does not?
Calibration. A duplicator that has drifted half a depth cuts a key that turns a fresh lock and fails a worn one. A shop that checks its machine against a gauge produces keys that work everywhere.
How many copies of a copy is too many?
Two. Each generation adds error. After the second copy of a copy, cut from the original code instead.
Does the blank brand matter?
Yes. Soft aftermarket brass wears fast and can shed material inside a lock. Good blanks cost pennies more and last years longer.
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