keying-systems

Pin Bitting Tolerances: +/- 0.015mm CNC Cutting Precision Standards

Engineering Overview: Technical specifications for CNC key cutting and pin broaching tolerances, evaluating shear line clearances and key smoothness.

Technical & Engineering Specifications

Standard ISO 2768 Precision Fine / DIN 18252
Tolerances CNC Key Cuts +/- 0.015 mm / Pins +/- 0.005 mm
Surface Roughness Ra < 0.4 um Internal Chamber Finish
Diametral Clearance 0.030 mm Optimal Shear Clearance

Sub-Mil Tolerancing in Lock Manufacturing

Smooth key operation and high pick resistance depend on exact manufacturing tolerances:

  • Pin Diameter: $\Phi 2.40 ext{ mm} \pm 0.005 ext{ mm}$.
  • Chamber Bore: $\Phi 2.43 ext{ mm} \pm 0.005 ext{ mm}$ ($0.03 ext{ mm}$ diametral clearance).
  • CNC Key Cut Depth: Machined to $\pm 0.015 ext{ mm}$.

Tighter tolerances prevent cylinder plug wobbling while ensuring effortless key insertion over 100,000 operational cycles.

Frequently Asked Engineering & Selection Questions

Q1: Why are tight pin tolerances important in lock cylinders?

Tolerances within +/-0.015 mm prevent lock picking, eliminate key binding, and ensure the lock operates smoothly over 100,000 cycles.