A Raised Spiral on Spanish Hitching

Here is a tutorial for a raised spiral of 14 parts which is worked into Spanish Hitching (SH). The small sample to be worked will be sufficient to show the method. The SH was made with 20 strands of grey VB cord (2mm) over a core of 18mm dowel. The SH is ABOK#3555.
The white cord is 2.5 mm although 2 mm would suffice. Take 2 lengths of this cord, double them, and insert them into the SH as shown. The ends are stiffened, pointed and slightly bent at the tips.
Work the bights snugly into the lay of the SH. We will be working these 4 ends down helically, from top right to bottom left, into the hitches formed by the same grey cord. I prefer  using a small spike for this phase of the work to minimise distortion of the hitches although a small lacing needle can be used.
Take the top end and pass it under the next available hitch from right to left.
As a rough guide to the amount of slack to leave in the bights, shown here is a piece of 9mm dowel which just passes comfortably through the bight.
Again, take the top white strand and pass it similarly to the first, from right to left, under the next available hitch. Also shown here is the spike ready to work a little slack into the next hitch to be passed under with the next white strand.
Proceed in this way until the desired length is reached.
All cords introduced hereafter will be 2mm.
These two purple strands are started on the bight similar to the white ones. They are entered in the same space, from right to left, but emerge from different ones as shown.
With top left, from left to right, go over 2 white (W), under purple (P) and under 2 white.
Over 2W, under 2W as shown.
With top right, from right to left, over 1W, under 2W and over all P.
With the same strand, over 2W, under 2W. All P's are now on the right and are in prime position.
With top right, over 2W and under 2W. Also over all P's.
As before, with the same strand, over 2W and under 2W.
Repeat the directions for steps 12 and 13 throughout. You may have noticed that the white and purple strands form 8-strand square sennit but turned through 45 degrees from the way it is normally shown!
Here a green cord is centred  through the  first purple bight on the left.
As shown, lace down with the green strands into the purple bights. Work the green strands as for a 2-strand left-handed grommet.
Finished on the left.
Same as before. A left-handed grommet.
Finished with green.
Here a red strand is introduced as shown. This time work the two reds into the white bights as a right-handed grommet.
All done and fully tightened!
Different perspectives.
  
I would suggest, for tightening, the following procedure :

1.  Although I didn't do this in the tutorial, when working the green strands fully tighten them as you go. Provided that there is not too much play in the purple bights, you will only have to tighten once. Proceed as you would when tightening your shoe laces.

2.  Fully tighten the white strands. Small pliers are best for this.

3.  Fully tighten the purple strands.  Alternatively, if the purples are tightened before the whites, you will get a more pronounced white ridge down the centre and the cross-section will be more triangular.

4.  Finally, fully tighten the red strands.
This final photo may show this…

For this 20-cord SH you could work a spiral into every 4th cord which would give you 5 spirals or work every 5th cord which would give you 4 spirals.

Here ends this tutorial.