Fluorocarbon overview

Fluorocarbon in six tables: soft vs stiff, main line or leader, diameter and abrasion, sinking and visibility, colour, knots and care.

Fluorocarbon = clear + sinks (SG ≈ 1.78) + abrasion-resistant + on the stiff side. Soft and stiff FC are the same material made differently. Choose the job first (main line or leader), then soft or stiff, then the diameter.

1. Soft vs stiff — Stiffness = formula × process × diameter⁴. Plain PVDF is stiff; a copolymer and a different process make it soft. The same line one size heavier is much stiffer…
2. Main line or leader — Baitcaster: fluorocarbon works fine as a main line. Spinning: it works but needs care, so most anglers run a PE main line + FC leader. Carolina rig: two contact zones A…
3. Diameter, strength and abrasion — Same strength: PE is thinnest, FC and nylon far thicker. Same diameter: PE is strongest. Fluorocarbon's strengths are abrasion and sinking, not thinness. All labelled…
4. Sinking and visibility — Fluorocarbon is far heavier than water (SG ≈ 1.78): the only one of the three main lines that truly sinks fast. "Invisible" has no fish-vision study behind it: it just…
5. Colour — Colour has nothing to do with soft or stiff: one line can come clear or tinted, and tint does not make it stronger, softer or invisible. For choosing a colour, see the…
6. Knots, care and troubleshooting — Fluorocarbon's weak spot is the knot: stiff FC measured only about 71–76% knotted. Wet it, cinch slowly, avoid friction heat, and test-pull. Troubleshooting Sources…