[TheBserk] made himself a set of auto-locking and auto-retracting hidden blades inspired by those in the game Assassin’s Creed. As you can see in the demo (and build guides) after the break, they work really well. We don’t like the idea of sharpened metal ramming its way past our wrists. But it’s not the first time we’ve seen dangerous arm-mounted hacks.

Reminiscent of Taxi Driver, [TheBserk] uses drawer slides from the local home store for his build. They are cut to length, and modified using springs for the automatic action. There is a lock to keep the blade extended, and a pull-wire to actuate it. Although dangerous, the build is well done. We think someone has mechanical engineering in his future, and possibly a trip to the emergency room.

The demonstration

Build guide part 1

Build guide part 2

[Thanks Kentaro]