Leader Construction for Saltwater fly fishing, by Serge Thomas

There are many formulas that people use to build leaders for saltwater fishing. A leader is the monofilament line that is attached to the fly line. The leader is attached to the fly line using either a nail knot, a jam knot (Billy Pate= kinda a slim beauty) or a loop to loop. Though I like the jam knot a lot, I think that the loop to loop connection does not get stuck in the guides as much as the two other connections.

A leader should be tapered. This means that it needs to have a butt section of higher diameter than the following section. To the extreme, for trout fishing, each section is sometimes of similar length (though the diameter decreases as you move towards the tippet). This is good for very delicate presentations and it matches well with DT or long belly fly lines. I would call these leaders “smoothly tapered”. However, for saltwater fishing, you want something more “agressively tapered”. I like Lefty’s formula that you can find in his book “Presenting the fly” (to me his best). I like also the one found in Lou Tabory’s book. However, I have decided to develop my own leader formula because I wanted one that would be easy to build from scratch in the field. I am kinda lazy and indeed never have pre-made leaders with me.

The idea is to make a leader built with sections that decrease in length in a very predictable way… without the need of a meter stick. My rule is very simple: each section of thinner diameter is half the length ot the previous thicker one. There is no need to measure the length of the following section: just fold the previous section in half and use that half-length as a template for the next section… and so on.

Example: Line 7-8 (bonefish)

6’of 40#; 3′ of 30#; 1.5’of 20#; 0.75′ of 16#; 4′ of tippet (8 to 16# test Fluorocarbon) =(6; 6/2; 6/2/2; 6/2/2/2)

For lines 6-7, I use a 30# butt section, for 7-8 I use a 40# butt section, for 9 and above, I use a 50# butt section.

Note, that when you go up in line weight, the butt has a thicker butt section, and, as such, you will need to decrease the initial length of the butt section (or you will end with a very long leader).

I build my leaders using Mason Hard Mono. I like it a lot. It is very stiff and helps turning over bulky flies when it is windy… the drawback is that it is quite hard to knot and on calm days, it can actually open a bit too abruptly. Lefty Kreh prefers to use softer butt section made out of monofilament that matches the overall stiffness of the fly line. He like to use Suffix Tritanium PLUS. Most of the guides in South Florida use Mason Hard mono, even for the tippet. Mason hard has aslo a great abrasion resistance and is a must for those who fish coral environments.

The connections between each piece of nylon is made using a nail knot to nail knot loop. I find that this is a slim and neat connection. It is not a strong connection, but the different sections of mono are stronger than the class tippet.

HOWEVER, the last connection is made with either a bimini twist (when a bite tippet is requiered)… or a lefty Kreh loop (for bonefishing). With a bite tippet, the last section of the leader has a double bimini twist at both ends (= class ; generally 16# mason hard mono).

– With a bite monofilament tippet: I connect the 16# section (loop of bimini twist) to the thick mono using a slim beauty knot (e.g. tarpon leader)

– With a wire tippet: I connect the 16# section (loop of bimini twist) to the wire with an Albright knot (e.g. shark leader)

– with no class tippet: I connect the 16# section (loop of Lefty Kreh knot) with a double loop to loop (lefty kreh loops at both ends; e.g. bonefish leader)

Note that either the Lefty Kreh and the Bimini twist knots are 100% knot strength. However, the Bimini twist has a superior shock absorbance, and as such, it is better to built a leader for tarpon fishing.

The overall length of my leader is different depending on the conditions (and the line I cast), but in general, I use:

– 14-18′ long for calm conditions

– 12-14′ for all around situations

– 10′ windy conditions (20 knot).

I tend to favor Seaguar Fluorocarbon for my bite tippet for tarpons and bonefish. For bonefish, I espcially am found of Seaguar Gmax which has the highest strength to diameter ratio.

If any questions, please advise.

Here is a diagram of my leader. On top is a bonefish type (works also for redfish) leader, and on the bottom a modified one for tarpon fishing.

Not that the nail to nail knots to connect the different pieces of mono is optional. A surgeon’s knot or a blood knot would work too. I just like the nail to nail knot, because it cannot slips.. since, if one tag end slips, the whole knot still closes. Trim the tag ends of the nail to nail knot as close to the knot as possible.

For the knots, you can search the internet or try this link http://home.cfl.rr.com/floridafishing/knot.htm