How to Tie the Surgeons Knot For Leader to Leader Connections
Surgeons Knot — (Break Strength 95%+) This knot is used primarily to join two pieces of leader of dissimilar size. Or to attach a shock leader to a fly line. This is a reasonably easy knot to tie but one that is hard to draw.
Lay two pieces of leader to be joined parallel next to each other with about six inches overlap.
Using the tag end of the piece of leader pointing to your right and the entire standing piece of leader pointing to your right tie an overhand knot in the middle of the overlapped parallel pieces. (See single overhand knot below with a single piece of leader. This is the same thing with two pieces of leader forming the overhand knot)
Grasping the both tag ends and standing ends gently pull the overhand knot partly closed.
Tie another wrap in the overhand knot using the right hand tag piece and the right hand standing piece. You should now have two wraps in the overhand knot with both pieces of leader.
Wet the knot. Grasp both tag ends and standing pieces. Pull steadily until the knot wraps tight. Finished knot will look like this.
Knots such as the blood knot or other knots that leave tag ends exposed or bumps in the leaders can catch rocks or twigs in the stream more easily than the double uni-knot or triple surgeon’s knot.
Triple Surgeon’s Knot is my favorite for leader to leader to leader connections because it is easy to tie and offers almost 100% break strength.