We will cover the Needle Knot here for the line- leader connection. Â I personally prefer a Needle Knot to the Loop to Loop connection because it is a smoother, low profile connection. Â Both connections are quite strong and provide very similar results when the line and leader are matched correctly. Â To tie the Needle Knot you will need to cut the existing loop off of your fly line if one is present.

Step 1

Tools needed: One large eyed needle for the nail knot, one small eyed needle for pulling the leader through the fly line core, sharp razor blade, pliers, leader and fly line.

Step 2

Shave down the butt of your leader (approximately 1/2 to 1″ long) with the razor blade. Â The butt of the leader needs to be small enough to fit through the eye of your small needle.

Step 3

Insert your small needle into the core of the fly line and out the side. Â I like to run the needle out of the core of the fly line approximately 1/4″ from the end.

Step 4

Place your leader in the eye of the needle and pull it through the core of the fly line.

Step 5

Once you have pulled the leader through the core of the fly line, snip the shaved part of the leader off.

Step 6

Nail Knot: At this time, you will tie a nail knot to finish your connection. Â Place your large needle beside your fly line and wrap the butt of the leader around the needle five times. Once this is completed, run the butt of the leader through the eye of the needle. Â Place needle as shown and wrap from the point to the eye.

Step 7

Pull the needle through the wraps you just made. Â I like to hold the wraps snugly while I pull the needle out. Â If your knot loosens up and looks like this, don’t panic, simply push the wraps together with your thumb nails as you gently pull on the leader and the tag end.

Step 8

Place your wraps (nail knot) close to the point at which the leader comes out of the center of the fly line. Once you are happy with your wraps, cinch down on the knot by pulling on the tag end and the leader.
Snip the tag end off and you are ready to fish. Â I like to place Pliobond or Aquaseal to this knot to create a smooth transition from the fly line to the leader.
Carefully inspect your line-leader connection often throughout the season. Â If you notice the fly line coating starting to crack at this connection, simply snip off the old connection and start over with step one of this post.
The Needle Knot is preferred by many anglers since it pulls through the center of the fly line and does not leave as large of a knot as just a Nail Knot alone. Â This knot works very well for most types of freshwater fly fishing. Â To tie an “Improved Needle Knot”, simply add a second nail knot above the first nail knot. Â This improvement allows the leader to create more friction on the core of the fly line and therefore creates a stronger connection. Â I prefer an Albright Knot or Bimini Twist in most saltwater situations and when targeting large salmon, steelhead or trout.
We, along with many guides and serious fly fisherman, strongly discourage the use of the barbed eyes, that are marketed for the line-leader connection. Â These work by inserting them into the end of the fly line and tying the leader to the eye.
Another less than desirable line-leader connection is the Braided Loop connectors that work by cinching down (think Chinese Finger Cuffs) on the fly line as tension is applies to the loop, the problem is that they can fail completely without any warning.
With the Needle Knot, Nail Knot, Bimini Twist and Albright Knot you can easily inspect them for damage and replace when necessary.
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