Chained Square

This CAD model was designed by Oskar van Deventer, copyright (c), 7 May 2025.

Chained Square has 16 squares that are connected with ball chain. This gives it great flexibility, as observed by Peter Knoppers. The goal is to fold a 4x4 square. The puzzle has several other challenges as well. The puzzle is difficult because of the tetrahedral topology of the weave pattern, and the lack of "simple conventional" solutions.

The puzzle uses ball chain with 2-mm balls and 1-mm spacing between balls. Eighteen pieces of ball chain with six balls each are needed to weave the pattern. The 3D-printer should be paused at the right height to insert the ball-chain pieces.

Here are some links about this design.
https://www.youtube.com/watch?v=q_Jp1tiGc1Q
https://www.etsy.com/listing/4348768821/chained-square-can-you-fit-the-puzzle
https://twistypuzzles.com/forum/viewtopic.php?t=40360

Feel free to 3D-print an extra sample to give to a friend, as long as you mention the designer and don't charge money.

If you are planning to sell some samples, then please contact me for a license agreement. The royalty fee is 10% of your selling price.

Please do not upload the design to a commercial service, or redistribute the design in any way other than linking to the YouTube video: https://www.youtube.com/watch?v=q_Jp1tiGc1Q

Enjoy!

Oskar
9 August 2025

Contact: 
https://oskarvandeventer.nl/index_contact.php?subject=Print%20It%20Yourself


