Readers may wonder about the connection between threads and arches. It is not as sketchy as you might think. I have been exercised for some time about the spiral cut stones in skew arches. That was emphasised when I spotted some nonsense in a paper published by the Institution of Civil Engineers. The author said that masons would have trimmed the stones to fit on site.
On the contrary, the engineers made templates to describe the spiral faces and they were cut to fit (https://lh3.googleusercontent.com/EwuHWdWPNyqWXXkUEewNhrO6zHjpkVlDyHtbx7_CVT0=w288-h162-p-no)
This is obviously coarser than a machine screw, but look at the scale.