The 6-piece knot puzzles are composed of six square rods. Each rod can be thought of as being made from 24 cubes. The outer (orange) cubes are present in all rods, while some of the inner (yellow) cubes are removed.

Common names for this well-known 6-piece puzzle include burr puzzle, Chinese cross puzzle, and devil’s knot. It exists in numerous variations and difficulty levels.

Of the two versions shown here, the solution for Knot 2 is significantly more difficult to find than the solution for Knot 1.

The 3D-printing templates each consist of 6 knot rods.