Counter-Milled Annular Ledges (0.20mm Depth) for Mechanical Spool Trapping
Engineering Overview: Technical analysis of counter-milled annular ledges inside brass cylinder chambers, creating mechanical hooks that lock spool pins during picking.
Technical & Engineering Specifications
| Standard | EN 1303:2015 Key Security Grade 6 |
|---|---|
| Ledge Depth | 0.20 mm Annular Locking Lip |
| Chamber Design | Precision Counter-Milled / Undercut Chamber Bores |
| Security Synergy | Pairs with Spool and Mushroom Driver Pins |
Annular Ledge Trapping Mechanics
Standard cylindrical chambers allow spool pins to slip past false sets. Counter-Milled Pin Chambers introduce internal horizontal grooves.
Mechanical Ledge Hooking
- 0.2 mm Annular Lip: Milled inside the chamber wall at the shear line.
- Deadlock Action: When picked into a false set, the spool pin lip drops into the counter-milled ledge and physically hooks, locking the plug tight.
Frequently Asked Engineering & Selection Questions
Q1: What anti-attack mechanism is detailed here?
Technical analysis of counter-milled annular ledges inside brass cylinder chambers, creating mechanical hooks that lock spool pins during picking.