Step 1

The spiral half knot is made from 4 cords. Let us number them 1 to 4 from left to right as shown in diagram 1. Cords 1 and 4 are the working cords, and the cords 2 and 3 are filler cords and just pass through the middle of the half knots.

Step 2

Begin by passing the working cord 4 to the left behind the filler cords 2 and 3 and in front of the working cord 1 as shown in diagram 2.

Step 3

Take the working cord 1 and pass it to the right in front of the filler cords and through the loop made by cord 4 so that it passes behind cord 4 as shown in diagram 3.

Step 4

Gently pull the knot tight by pulling on the working cords

Step 5

Now we just repeat the previous steps to form the next identical half knot.

Pass the working cord 1 to the left behind the filler cords 2 and 3 and in front of the working cord 4 as shown in diagram 5.

Step 6

Take the working cord 4 and pass it to the right in front of the filler cords and through the loop made by cord 1 so that it passes behind cord 1 as shown in diagram 6.

Step 7

Gently pull the knot tight by pulling on the working cords

Step 8

Repeat until you have the desired length of spiral half knots.  The diagram below is a flat schematic, but repeating spiral half knots forms a natural spiral without you needing to do anything more than just repeat the same half knot over again.

There are left- and right-handed variants of this knot, where the spiral twists to the left or the right. This can be seen in this section of the Helix wall hanging below.