Ashley has a good description of ropemaking, with illustrations of all the tools. It's oriented around the regular sailing ship practice of remaking old rope into new; the video doesn't make clear what's happening at several points. It was interesting to see the preparation of the hemp; that's not covered by Ashley.
I've found it quite useful to know how rope is laid up from time to time, for example if a rope comes unlaid. You can re-lay it if necessary.
The video shows a rather unusual 4-strand rope with only two yarns per strand. Very unlike the 3-strand rope we use. But the overall technique is the same.
I remember as a boy, going along in the bus to the local roperie on a Saturday morning. I wanted 40 fathoms of 2" (circumference) rope for a running mooring.
"Sorry, we don't have any of that size in stock, but if you like to wait half an hour, we'll make it for you".
And they did, and it was fascinating to watch it being done.
The Cordonerie Royal in Rochefort is worth a look. Used to mke the ropes for the French fleet. Very long building with several bits of interesting machinery to twist them up.
Fascinating, thanks for sharing the video. I suppose the brown fluid is tar of some sort.
An idea has just popped into my head: joining the ends of two 3-strand ropes together with a short splice; but slightly different sizes.
I wonder what is possible?