Knotless leaders and lines are used by many fly fishermen. Although still available for purchase, hand-tied knotted leaders have pretty much been replaced by manufactured tapered leaders. Attaching a knotless tapered leader to the main fly line without a knot is done with a specialised technique. A few basic materials are involved that are not commonly associated with knot tying. The resulting knotless leader-to-line connect is strong and will move through the line guides smoothly.
Hold the fly line so that 2 inches of the free end is accessible. Trim the end of the fly line flush with scissors.
Insert the point of a sewing needle into the fly line 1 inch from the end. Insert at a downward angle toward the free end. Push the needle down the centre of the hollow fly line until the point extends from the end of the line. Leave the eye of the needle extending from the fly line at the point where it was inserted.
Thread the small diameter end of the knotless leader through the eye of the needle.
Pull the needle and leader through and out the end of the fly line. Continue to pull the leader through the fly line until 1 inch of the leader is left extending from the point where the needle was originally inserted into the line.
Lightly sand the leader with fine-grit sandpaper. Sand the first 1 inch of the leader extending from the end of the fly line.
Apply quick-dry glue to the sanded length of the leader. Grasp the inch of leader extending from the fly line at the needle insertion point. Pull the glued leader back up and into the fly line.
Trim the leader extending from the needle insertion point flush with the fly line. Use a razor blade to trim the leader. Apply a drop of quick-dry glue to the hole in the fly line.