Customizable Knex Lock and Key (Prototype Cylinder Mechanism)





Introduction: Customizable Knex Lock and Key (Prototype Cylinder Mechanism)

Hello Boys and Girls!

     Thanks to the addictive nature of designing and building with Knex, I have spent the last two days designing a new type of lock and key.  My goal was to create a lock that works as much like a cylinder lock as possible. I also wanted the key to be unique to the individual lock. By using tumblers of different sizes, you can customize the key. The prototype pictured only has two tumblers, but can be built to have as many as desired.

      When you put the key in the lock's body and turn counter-clockwise the teeth on the key will push the grey wheels up. The wheels give a smooth surface for the key's teeth to turn against. Sitting on top of the grey wheels are plates that act as the tumblers. To customize the lock you lay an orange connector on top of the tumblers that correspond with the short teeth on the key. When locked, the top of the tumblers will be be at different heights. When you turn the key, the tumblers will all rise to a uniform height.  That pushes a connector, that is on a pivot, up. This can be used to unlock a pin, or whatever you want to connect to it.

One thing I did not want to do was use any rubber bands. I got around this by using flexible rods to keep pressure on the tumblers so it will re-lock when the key is removed. Also, unlike most of my previous builds, it uses no modified parts.

     I would love to hear any feedback you have to give.
Until next time,



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    I would love to hear any suggestions you have for future projects!

    I also have a prototype but am kinda stuck with how it's goin

    A decent horizontal magazine gun, as many have been attempted, but minimal success has been achieved. Or if they do function smoothly they require to many pieces.

    A ball machine :P

    awe >.<
    How about some small gadgets a lock? :P

    Erm, more like, um, i once tried myself on making a rubiks cube out of knex ^.^

    I actually thought about that. I'll have to look into it.

    yay, ball machines of any size are fun! :D

    If you want something small, you can also make a small ball machine ;)