1. The Theory of the Shear Line
A lock is a puzzle made of metal. Inside the brass cylinder are stacks of pins pushed down by springs. The Key Pins (bottom) and Driver Pins (top) meet at a specific point. To rotate the lock, the gap between these pins must align perfectly with the edge of the cylinder. This is called the Shear Line.
Drag the slider to insert the virtual key.
2. The Imperfection
If locks were perfect, picking would be impossible. But manufacturing is never perfect. The holes drilled for the pins are never perfectly straight. When you apply rotation (torque) with the tension wrench, the plug hits one pin stack before the others.
Increase tension to see which pin binds first.
3. The Attack (Picking)
Now we apply the hack. We use the tension wrench to rotate the plug and bind the pins. Then, we use the pick to lift the binding pin until it clears the shear line. The plug turns slightly more, trapping the driver pin above the line.
Desktop: Hold Spacebar for Tension, Mouse to Pick.
Mobile: Hold 'Tension' button, Drag finger to Pick.
4. The Bypass (Shimming)
Picking attacks the pins. But sometimes, it's easier to attack the latch. Padlocks have a spring-loaded pawl that holds the shackle. By sliding a thin piece of metal (a shim) down the shackle, we can push the spring back directly, bypassing the key entirely.