So I've been trying to tie an FG knot recently, and have managed to tie it pretty well on heavier leader lines, but cannot manage to get it to tighten on smaller leader lines. 15lb braid to 15lb flouro works fine. Using 15lb braid to 8lb flouro, and the knot just slides. Is the diameter or 8lb flouro just too small for this to work, or has anyone figured out how to make this work?