"Precision CNC machining" appears on every machine shop's website — but what actually makes machining precision, and how tight is precise? Here is a clear answer.
What is precision CNC machining?
Precision CNC machining is computer-controlled machining that produces components to tight tolerances with high repeatability. CNC — Computer Numerical Control — means the machine follows a programmed path automatically, moving the tool and workpiece precisely and reproducing that path identically on every part. "Precision" adds the requirement that the results are close-tolerance, verified and repeatable.
What makes machining 'precision'?
Three things separate precision machining from general machining:
- Tolerance — how closely the part matches the drawing (often a few hundredths of a millimetre or finer).
- Verification — the tolerance is measured and proven, typically by CMM inspection.
- Repeatability — the same result is achieved on every part in the batch.
A shop that holds tight tolerances but can't prove or repeat them is not doing precision work.
How tight are precision tolerances?
It depends on the process and material. Precision milling and precision turning can hold tolerances as tight as ±0.005 mm (±0.0002") where the application demands it. What makes the number meaningful is that it is CMM-verified — measured against the drawing, not assumed.
What precision machining does Milltech offer?
Milltech offers 3, 4 and 5-axis CNC milling and CNC turning to ±0.005 mm, all CMM-verified, across a fleet of 40+ CNC machines. Work runs from a single prototype to repeatable production, with full material and process traceability.
