As soon as I saw this task I knew the lock I wanted to pick.

A dozen years ago when my siblings and I still lived with our parents, my brother had a lockable fireproof box. He claimed that he kept some precious photos and notebooks in there that he wouldn't want to lose in case of a fire. But he took great care to make sure that we never saw inside.

That forbidden box has languished in my mum's attic for nigh on a decade - I noticed it there in a cobwebbed corner a while ago.

This task finally catalysed my curiosity into action...

Phase 1: Learning to pick locks


Diagram 1: A lock is composed of a series of spring-loaded stacks called pin stacks. Each pin stack is composed of two pins that are stacked on top of each other: the key pin, which touches the key when it is inserted, and the driver pin, which is spring driven. When the proper key is inserted into the lock, all of the key pins and driver pins align, as illustrated, allowing the cylinder to be turned. When no key or the wrong key is in the lock, the pin misalignment prevents the cylinder from being turned.


Diagram 2: To pick a lock you need two tools. One to provide torque, and one to push the pin stacks into alignment. You need to apply a gentle rotary pressure with the first tool, so that as you push up each pin stack it catches on the shear line. When you have managed to catch all of the pin stacks, the lock will turn.

Phase 2: Theory into practice


This is the forbidden box, and the tools I used to pick the lock. Two paperclips (one for torque and one for pushing up the pin stacks) and pliers to bend them with. Turns out it's not easy. Which I suppose is a good thing.

The problem was that as I pushed up each pin stack, it didn't catch or click or give me any kind of clue when it reached the shear line. Most of the time it sprang straight back into place as soon as I stopped pushing it.

Occasionally, very occasionally, it would stay up. Briefly.
I could only see the first pin stack; the others were hidden in the depths of the lock. So I couldn't even see whether I had caught the back pin stacks. I had to just keep trying and trying until by chance I managed to get all of them to catch at the same time.

But in the end, with immense satisfaction, I succeeded. See the video of that glorious moment below. (I'll spare you the hour of poking away that preceded it.)

Do you want to know what was inside the box? Well, that's my brother's secret. It would be pure evil of me to show you...