Sunshine Recorder

Link: Illegal Engineering

An illustrated lecture about the history of Safes and Safe breaking. This is currently my favourite lecture to perform. There’s something very satisfying about the simple ingenuity of safes and locks. Its also an area of engineering design that has not been transformed by science or maths, and to me illustrates intuitive aspect of the subject, which often now gets forgotten.

In the last twenty years, the craft of safe cracking has tragically declined. It is no longer the glamorous activity featured in every other detective film, and the number of real criminal attacks on safes has fallen dramatically. So I’m delighted to see so many children in the audience as its time to start training up a new generation of safe crackers or it will become a lost art. I suspect this decline is linked to the general loss of practical mechanical skills – children today are no longer taught metalwork, just DT. A sound knowledge of metalwork would be very useful in breaking into a safe, but DT is no help at all.

At first glance a modern safe does look totally impregnable. The two locks, (one key and one combination) do not themselves open the door, they merely release the elaborate bolt mechanism. This pushes 50mm steel bolts out in all directions, securing every side of the safe door, even the hinge side. It is no use chopping the hinges off a safe, the bolts will still hold it as firmly shut as ever. If it looks virtually impossible to get in through the door, getting in through the walls or the back is no easier. They are about four inches thick, an inner and outer skin of steel, with the cavity between filled with extra strong concrete. The enormous weight of a safe makes it very difficult for thieves to carry it off, whole – it also makes the door very dangerous. Its extreme weight gives it such momentum when closing that it becomes a guillotine, chopping any fingers caught between door and frame.

Larger bank vault doors are often circular, with bolts that shoot out all round the edge. The reason for circular doors is simply that they are easier to make. Both door and frame can be cut accurately round on a large lathe to make them a snug fit. Getting a rectangular door to fit closely at every point is more difficult, particularly with its enormous weight, which can cause distortion.

Behind the door, bank vaults are massive, built in concrete structures. Criminals have had some success tunnelling their ways in. Adam Worth, a cerebrated Victorian criminal, made his initial fortune tunnelling into a bank in Boston. He then moved to England with his accomplice Piano Charlie where they both fell for an irish barmaid prostitute called Kitty Flynn. She eventually married Piano Charlie, but continued to sleep with both. Worth masterminded a huge variety of crimes in Britain, including stealing an entire diamond shipment from the Kimberley mines, and was not caught until 40 years later. He then, with his exploits publicised, became the inspiration for Sherlock Holmes’ adversary Moriarty. Both Worth and Piano Charlie died in poverty, but Kitty became a rich and litigious widow in New York.

Anyway, to counter the threat of tunnelling bank vaults started to incorporate ‘patrol passages’ round the outside to check no one is attempting to tunnel their way in. The invincibility of bank safes is so convincing that they are quite often left on open display (less so in Britain than most other parts of the world) as proof of the security of your money. Mies Van Der Rohe designed a particularly elegant bank in Torronto called the ’Transparent Bank’.

The need to keep precious and valuable possessions ‘safe’ is nothing new. The modern safe is directly descended from the medieval chests, now often found in museums and churches, used as collecting boxes. These chests were beautifully decorated, at first mainly made of wood, with iron hinges, locks and strappings. Later ones were entirely made of iron. The lids often had elaborate bolt work, like a modern safe. For extra security the keyhole would often be hidden under a secret flap, or disguised as part of the decoration. A few even had knives which shot out if the lock was tampered with. I’ve always admired these chests, they were obviously such important objects, so when my sister, who lived in Brixton, got burgled some years ago, I decided to make one for her. Large locks are great things to make, turning the key makes a wonderfully satisfying clunk, much better than any modern mass produced lock. To surprise the burglar, I incorporated a device that released a small explosive charge inside the lock when the key was turned, unless one of the side handles was first lifted. My hope was that this would be so unnerving that he would then run away. Unfortunately I never found whether it worked, my sister moved out of Brixton and hasn’t been burgled since.