Illustration of the origami method of Kongming Lock. How to fold Luban Lock by hand.

Kong Ming Suo, also known as Bagua Suo and Luban Suo, was an intellectual toy widely spread among Chinese people. Among the people, there are also names such as "Bie Sap", "Six Sons Alliance", "Mo Naihe" and "Nanrenmu". There is no need for nails or ropes, and it is completely supported by the connection of its own structure, just like a piece of paper that can stand upright after being folded in half, showing a seemingly simple but condensed extraordinary wisdom.

It is said that Kong Mingsuo was invented by Lu Ban from the late Spring and Autumn Period to the early Warring States Period. (There are also legends that it was invented by Zhuge Liang during the Three Kingdoms period) During the Three Kingdoms period, Kong Ming made Lu Bans invention into a toy-Kong Ming Lock.

Illustration of folding origami Kong Ming Lock.

The following takes one yuan as an example to demonstrate the folding method of Kong Ming Suo. First, fold the long side in half.

Measure 13x3=39mm from the middle crease to one side and fold the crease.

Turn over. The length of the short side of one yuan is 63mm. Because part of it needs to be stored inside, four equal parts are enough. Then measure the position of 13x4=52mm and divide it into four equal parts. The remaining 10mm is the part hidden inside.

At the beginning, divide it into three equal parts between the two vertical creases, making sure to leave only the crease in the middle part.

Fold out four hypotenuses.

Fold the outer sides to form an L shape.

Plug the two butt joints together to form a closed loop. Make sure the three closed loops are inserted together. See Figure 4 for details.