A little while ago, the inimitable Barry Wels was lured into helping US bypass tool manufacturer Lockmasters (“Serving those with a need to know”) set up a blog.
As one might expect, the result is well worth reading for anyone with an interest in physical security. They’ve already covered an interesting tactic — an alarm-triggered fog machine which creates near-zero visibility in the room, keeping burglars from seeing what they came to steal (or seeing where the employees are, and therefore being unable to hurt them in a holdup). But this latest bit of tech is even more interesting.
The device in question is a very finely machined security screw, which acts as a lock for your lock.
The reason is that, especially in Europe, locks are very easy to change out with ordinary tools. If you have a high security lock, this means someone could take advantage of a moment the door is open and outright steal the expensive cylinder.
Or, more likely, swap out the high-security cylinder for an invisibly modified one… which lets them come back and open the door whenever they like!
Additionally, being able to swap out the cylinder easily after picking it or drilling it could help an adversary eliminate forensic evidence of their evil doings. Thus this screw.
By driving a central pin down the center of a four-way-split machine screw, the screw becomes impossible to remove. In order to pull it out, you need a special tool that reaches inside the screw, unscrews the inner pin, and then (by using the threads inside the “outer” screw) removes the screw itself.
Sure, some part of me is wondering if you, perhaps, couldn’t make an inner-pin-unscrewer using a ballpoint pen refill and a hacksaw blade, and then unscrew the outer screw by screwing in an ordinary machine screw.
But hey, it IS a neat idea.