Welcome to Fly fishing and Fly Tying magazine's website, once you register, you'll gain access to the Blogs, Forum and Shop.

If you cannot register successfully, contact us.

Member Login

Lost your password?

Search This Site

Now you see it…

… now you don't! Mark Bowler asks if the condition of fluorocarbon determines how 'invisible' it is

An interesting article on leaders by Ally Gowans (Electing the best leaders, October 2016 issue) triggered a fascinating off-shoot and discovery as we worked on its production.

In the article, Ally was writing about making up his own tapered leaders for salmon, and described how he knots different diameters of leader to create a customised taper. When creating the step-down it is important not to join two lengths of monofilament that are markedly different in diameter, otherwise the knot can slip, the thinner nylon can be weakened, the transfer of energy down the leader is inhibited, and it creates a junction prone to tangling.

He uses a rule called the '2/3 rule' meaning the step-down length he's knotting his first length to should be no less than two-thirds its diameter (ie, he'll happily join 0.330mm to 0.435mm, but he wouldn't join 0.260mm directly to 0.435mm; he'd add a section of 0.330mm in between, as an intermediate section between the two).

In order to demonstrate this visually, I asked him if he could photograph a level junction, an efficient step-down, using the 2/3 rule, and a poor one, which breaks the 2/3 rule.
"I knew you would," he sighed, resignedly, and went off with his camera.

He rang me later to say he'd had a devil of a time photographing the three knots, but discovered something very interesting at the same time. All the leader material he was using for this demonstration was fluorocarbon, which has that great acclaim for fishermen in that fish can't see it. The reason for this claim is that fluorocarbon has a similar refractive index to water, so it doesn't appreciably distort light passing through the line, so fish (and humans) struggle to see it.

The trouble was, as Ally discovered, that it's also very difficult to get a camera to see it either, so he couldn't get the knots to show in his photo, irrespective of background.

He then reverted to some of the same fluorocarbon material that he'd already used in a leader for fishing. This, he found, was much easier to see, and showed up far better in the photographs. He wondered if the use of the fluorocarbon as a fishing line soon causes it to abrade, collect dirt and lose its sheen, so much so that it became more visible with use?

Certainly with photography the old, used fluorocarbon was far easier for the camera lens to pick up than fluorocarbon pulled brand-new, straight off the spool.

It begs the question: should we be knotting on clean, fresh, brand-new fluorocarbon for finicky, monofilament-shy fish? I might have to try it this week.

Existing comments

Leave your comment below

You must first login or register to leave comments

Back to top

Search the site