Knex Combination Lock

Introduction: Knex Combination Lock

About: Mechanical Engineering. Inactive?

Here is the K'nex Combination Lock. This is made from Micro K'nex to keep it small, but could be up-scaled to Classic K'nex.

WARNING: DO NOTtry to lock your room or hide your government secrets with this. Your arch-nemesis will give it a quick yank and the missile codes will be gone. Or your brother will just steal a quarter from you. Either way, this model isn't very useful.

Here's how a lock works:

Next...... Remote transforming Iron Hide

Step 1: Assembly

Based on where you leave out the peg on the second disc and how your number disc is positioned, everyone's combination will be different.

To find your combination and unlock:

Turn the disc until the front disc has its gap facing towards the grey connectors outside the lock. Check the number. Turn the number disc the other way until the second disc is in position. Check the number. Then turn the number disc the other way until the last disc is in position. Check the number. Now you have your combination. Push the grey connectors in to release the lock.

Step 2:

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    10 Discussions


    Question 4 weeks ago

    I built it but... How does it work?


    4 months ago

    Wow! I like it :-D


    6 months ago

    cool! how does it lock?


    Reply 6 months ago

    The black disks have only one position that the grey connectors on the side can fit into, which when they are pressed into the device, raise the purple connectors on top just enough to release the latch.