Re: lbs. to X conversion
3x should be more like 8-10lb.
Easiest way to remember is that 5x is generally 5lb, and it goes from there.
_x refers to diameter, not strength. Fluorocarbon will generally be stronger for the same "_x". But there's not going to be a universal chart, because breaking strength will vary from one mfg to the next. (Then there's the fact that 8lb spinning line will actually be closer to 11lb break strength, but that's a whole diff't ballgame)