Disc-Detainer / Abloy
Disc-detainer locks are a different mechanical philosophy — no springs, no pins, just a stack of rotating discs and a sidebar. Genuine Abloy Protec is one of the toughest locks a hobbyist can face.
At rest
A stack of rotating discs and a sidebar — no springs, no pins. Each disc has one deep TRUE gate (top) plus shallow false gates on the sides. At rest the gates are scrambled, so the sidebar is held out.
How it works
Rotating discs plus a sidebar. The key's angled cuts rotate each disc to a set angle; when every disc's true gate lines up along the sidebar channel, the sidebar drops in and the plug can rotate. High-security models add false gates on each disc that catch the sidebar and mimic a set.
Tools you need
A dedicated disc-detainer pick — a tension ring / collar plus a probe used to rotate individual discs. High-quality tooling matters, especially for genuine Abloy.
Step-by-step technique
- Apply tension with the tool's collar.
- Find the binding disc and rotate it through its angles until the sidebar begins to seat on its gate.
- Move through the disc stack, rotating each to its gate — without losing already-set discs.
- When all true gates align, the sidebar drops and the plug turns.
Common mistakes
- Using pin-tumbler tools — the geometry is wrong entirely.
- Losing set discs while working the stack.
Skill level & notes
Genuine Abloy Protec discs use false gates and tight tolerances and are very hard. Cheap disc-detainer copies are far easier — learn on a clear practice lock first.