Having built up quite a library of braiding books, when I come across a pattern which looks as though it might work using horse hair, I try it out.
The photo below shows a rounded flat braid. It is made on a round disc and the disc is not rotated, resulting in the finished effect.
Above the braid is straightened out. To the right you can see a gentle spiral effect
Pattern Details
The first diagram shows the start position of the horse hair
Now, starting right to left, move the bottom strand at position 1 to 15 and then move 15 to position 1. Moving north to south and south to north.
Do this with each set of vertical strands until all have changed places.
Lastly, the horizontal strands are moved east to west then west to east. 9 to 24 then 24 to 9
You are now ready to work the moves once more until you reach the length you want.