These instructions show how to make the K'nex lock and key created by you-tuber Richard Thiessen HERE and seen also by maxknex050 HERE. I give full credit of the design to Richard Thiessen but found it difficult to create the lock through the video and saw many requests for instructions so here they are. This lock style is called a mortise lock for those of you who were wondering. Now for some pros and cons.

Pros

Uses specific customizable key

Almost impossible to pick (adding an extension to the bottom left corner would make it completely impossible)

Very sturdy (you cant' just break the box open to unlock it)

Cons

It will occasionally jam after using an incorrect key or attempting to pick it (but it will jam in the locked position!)

If a part inside the box breaks you have to take the lock apart to fix it

TO THE INSTRUCTIONS!!!

Step 1: Making the Box

These are the outside edges and bottom of the box, follow the pictures and make the parts. If your confused read the notes. Most of the pictures are taken from the "back" of the box

Step 2: The "Levers"

These parts are called the levers and are the parts that allow (or don't allow) the rod to pass through. These parts are loose and are slid by the key. If you would like your key to be different these are the parts you should change or rearrange. After making the levers place them inn the box in the correct places, check the notes for help. Also in the last two pictures two green rods are missing but you should have already put them there. Ignore these missing pieces (they are marked by notes).

Step 3: The Top of the Box and the Bolt

The first pictures are to build the bolt then the top of the box. Two Y clips on the bolt are twisted the wrong way and are marked by notes. A later picture shows them the correct way. Follow the Pictures, check the notes (they are really helpful in this part)

Step 4: Key and Finish

Quickly build the key (or your specific key) and your finished! Slide the key into the opening depicted in the second picture, or watch the videos if you are still confused. Now build a safe or just spend hours trying to pick the lock. Ask questions if you need I check back regularly! And post any improvements or safes in the comments below!