All the pins are under spring pressure - the 'key pins' (i call them bottom pins usually) are all pushed out at their maximum anyway and only stopped by the profile of the keyway. All are at, or below, the shearline to begin with (they have to be) and it is the top pins that are pushed below the shearline. Inserting the corect key merely pushes the top pins back to the shearline against the spring pressure, (not past it or the bottom 'key' pins then block the shearline), so that the 'key' pins sit at the shearline also. A shear is formed between the cylinder and plug. In short, you can't pull the 'key' pins any further out/down/up than they are when at rest.
Unless the wise amongst you know another secret........
horsefeathers wrote:All the pins are under spring pressure - the 'key pins' (i call them bottom pins usually) are all pushed out at their maximum anyway and only stopped by the profile of the keyway. All are at, or below, the shearline to begin with (they have to be) and it is the top pins that are pushed below the shearline. Inserting the corect key merely pushes the top pins back to the shearline against the spring pressure, (not past it or the bottom 'key' pins then block the shearline), so that the 'key' pins sit at the shearline also. A shear is formed between the cylinder and plug. In short, you can't pull the 'key' pins any further out/down/up than they are when at rest.
Unless the wise amongst you know another secret........
regards
wayne
I think the intension was that if the pins had been pushed down or into the chambers and then frozen the bottom pins/key pins would need to be pulled up somehow back to the rest position and the springs would be made redundant.
