Ah well, I've used the weed whacker/strimmer line. It worked surprisingly well, although a narrower gauge would fit better (& probably work better in the weed whacker too*). Being larger diameter, it is even softer on the hand than the original line.
I whipped the ends for about an inch and a half & tested the whippings under load. I then glued the whippings with Epoxy resin, & smeared the ends of the mono with a solder iron to mushroom them out a little (per Miles' excellent rigging article).
*I bought the thickest whacker mono available some years ago -- thinking it would be tougher -- and it is, it lasts ages, but it doesn't auto-feed properly. I have a huge reel of this stuff, bought cheaply in the USA for about $5...probably a tiny fraction of the price of fancy Dyneema spear lines. Pity it's not green (or black or clear) though ...
