K'nex Lock

About: Hello, my name is Ondrew. My main interests all lie in design: from mechanical to digital to sound to graphic to... Past me finds it important to go to www.legoblockshell.org to help prevent Shell from da...

These are the instructions for my very own K'nex lock, first shown here.  The locking mechanism is powered entirely by tension, and when closed, it’s impossible to open it with force unless you rip apart the lock itself, or bend the pieces enough so you can yank the shackle out.  It is opened by pressing the button on the side shown by a note in the intro picture.   I could mess with this lock for hours.  I wouldn’t recommend actually locking anything with it, because someone’s just going to disassemble it.  Bad things could happen to your sweet loot, and we certainly don’t want that.

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Step 1: Piece Count

White Eight-Prong: 2
Red Three-Prong: 18
Grey Two-Prong: 3
Orange Two-Prong: 7
Grey One-Prong: 11
Tan One-Prong w/ Extruding Bit: 4
Orange One-Prong w/ Extruding Bit: 1
Small Blue One-Prong: 3

Green: 23
White: 17
Blue: 3

Y-Rods: 6

(It's always useful to grab a few extras just in case I'm off, and if I am inaccurate in the piece count, please tell me.  It took a while to make this piece count, but I am only human, and I easily could've made a mistake.  If you're confused about what piece I'm referring to when I assign it a name, please don't hesitate to ask.)

Step 2: Shackle

This is a rather long step in which you build the shackle.  The shackle was the most difficult part of this design, because I had to remake it multiple times so it could be as sturdy as possible, yet relatively thin, with a sizable hole in the middle.

Step 3: Lock Box

This is the part where all the magic happens.  Here, you build the mechanism that allows the lock to lock.

Step 4: Connect the Shackle & Lock Box/Finishing Touches

Finish it all up.

Step 5: Hours of Mindless Entertainment

Listen to this playlist or anything you want (relative silence works too), contemplate the universe, and fiddle with the lock you just built.  You've got enough mindless entertainment to last yourself quite a while.  Have fun!

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2 People Made This Project!


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41 Discussions


2 years ago

What is Orange One-Prong w/ Extruding Bit?


5 years ago

Hey man, thought I'd add to the build streak and make one too! I didn't time myself though...

14, 7:36 PM.jpg14, 7:36 PM.jpg
5 replies

My, the list of builders just keeps growing. Timing, schmiming. Thanks for taking the time to build this. (The mechanism is working for you too, I assume?)

Yes, this 'ible has my personal record for people who have built it, and I'm quite proud of that. ^¬^

I understand: you are on a mission to build as many awesome K'nex Model Guns as possible, and you're doing a marvelous job. Keep it coming, and you don't really need to worry about breaking yourself from K'nex gun land. ø_ø


5 years ago on Introduction

Yo DO! I just made another one and combined both to form handcuffs! Of course, it uses more parts but they actually work (but they do break when you apply too much force)! Want some pictures?

2 replies

Yes, I'd love to see some pictures. You can feel free to post it too if you give me credit and link it to this. They sound awesome. :p