If those nanofibers...spoiler
If those nanofibers can cut through anything - a ship or a diamond - what's holding on to them? Why wouldn't they cut through their anchorage?
sharePerhaps the fibres become thicker near the ends. It's only their thinness that gives them cutting ability.
shareThat makes sense, although I didn't see any evidence of that in either cutting scene.
Here's another idea: they're wrapped around a cylinder that's first wrapped with a woven textile of the same fibers.
What would happen if two fibers met at 90°?