Trefoil Knot Geometric Model. A straw craft project with 3D printed connectors.

Connecting the free ends of an overhand knot produces the simplest Gordian knot, the “trefoil knot.” It has a threefold axis of rotational symmetry.

Files –
T-10mm 1x
T4-10mm 4x

The diameters of the connectors are 10mm and can be scaled to any diameter. Eg – if a diameter of 11.6mm is required, just scale the part to 116%.

The large straws in this model have a nominal diameter of 12mm. For this pack of straws which I obtain the internal diameter vary between 11.3 to 11.8 mm for different colors.

The Trefoil Knot is assembled from 3 similarly build sections as shown. The length of the sides can be scaled accordingly if you used a different straw diameter.

This is printed in PLA with support.

Full disclosure: Straw connectors and geometric models are not my own original idea. The concept exists (or has existed) commercially, and there are many people tinkering with this on Thingiverse.