Sounds as if you’ve got it sorted just in time for a Xmas rendition of Cod Rest ye Merry Gentlemen or Hake the Herald Angels Sing. (My sincere apologies for opening the door to a million bad fish-based puns.)

The Extruder -the machine who produces the Line- don’t care if it is used for fishing or stringing Instrument or toothbrush. It’s all up on big coils.

And, if you go over to the Tennis People you might find the carbon.

Firstly, if you are going to compare string prices for a mark up you really need to compare the same material, not nylon with gut strings. Just on the nylon, it is extruded in only a few thicknesses, relatively, and proper harp strings are ‘rectified’ polished down to a different thickness for each note and I believe are also rounder than fishing line. This will make it sound better – or less bad anyway, I really prefer gut! There will be a mark up for not buying 20m a time and labelling it, but not as great as you say.

Fishing line is a perfectly fine idea if you are not going to play the harp seriously and want it more for cosmetics, but harpists aren’t just madly throwing money away on our more expensive proper strings.

When harp strings are prepared to be sold as such, I understood that they are passed through a diamond die so that they are perfectly cylindrical and therefore the sound vibrations they produce are more perfect and regular than would be the case with fishing line. Will someone inside the string industry comment here?

Yes, I remember using fishing lines too for some instruments when I started playing music long time ago. Remembered they don’t ring as long though and faced some difficulties with harmonics but otherwise worked perfectly.