(Note if you are reading this thread and not seeing the parts list: it's an attached image and you need to be logged in to see it)
Wonderful! Thanks Chris for this contribution to the community!
Silly question: Why doesn't the string unwind itself when you remove it from the rig?
I think the idea is that the (pairs of) threads are twisted individually in one direction while the whole thing is twisted in the other. For one to untwist it has to twist the other even more, so their torques balance out. But I am like you, it is surprising that it works so well. I need to think in detail about it.