Flex Zap line splicing method
The splicing method that follows is pretty much "chapter-and-verse" from the Trey Combs book STEELHEAD FLY FISHING AND FLIES, Frank Amato pub. 1976, pp. 53-4. Combs credits the great Washington State steelheader Harry Lemire for directions on its implementation. This method will allow you to create strong, durable splices in any fly line and is the method I use to create my own "one piece" custom Spey lines.
You´ll need the following stuff: line sections, pin vise, beading needle (or long thin sewing needle), dental floss, a razor blade, some hemostats, and a slow curing flexible cyanoacrylate super glue like Flex Zap (available from Pacer Technology, Rancho Cucamonga, CA 91730, but your local fly shop should be able to get some for you)
1. Let´s assume we are splicing a section of 11 weight floating line and a section of floating 12 weight. Cut both sections so the butt ends are square. Strip the coating off the butt section of the 11, leaving @ 1 of the Dacron core exposed.
2. Combs recommends removing the sharp point off the needle before use. This is important because you´ll need the needle to create a big enough channel through the 12 weight line core to allow you to pull the 11 weight core through it. Place the eye end of the beading needle in the pin vise and work the needle directly into the core at the cut point on the 12 weight line. Work the needle in about an inch, or the same length as the stripped portion of the 11 weight line. I tend to repeat this procedure several times to ensure that there is enough room created for the 11 weight core.
3. Now double the 12 weight line over where the tip of the needle is and force
the tip of the needle out through the line coating. Be sure that the amount of
tip outside the coating is sufficient for you to clamp it into the pin vise.
4. Remove the vise from the eye end of the needle. Cut a piece of dental loss @
a foot long and thread the two ends through the eye of the needle.
5. Attach the pin vise to the tip of the needle and pull the needle and most of
the floss through the line. Leave a small loop of floss about the size of a
penny protruding from the cut point. Remove the ends of the floss from the
6. With your hemostats, grasp the ends of the dental floss, then twist the
floss around the jaws of the hemostats.
7. Take the Dacron core of the 11 weight and fray out the end of it. You need enough frayed so that the loop of floss has something to hang on to as you pull the floss and Dacron core through the center of the 12 weight line. Combs recommends fraying at least 1/8 of the core; I´ve sometimes had to fray up to 1/4". Place the frayed section of core into the loop of floss and use the hemostats to pull the floss loop into the 12 weight so that the frayed section of core is snug up against the 12 weight line.
8. Liberally coat the Dacron core of the 11 weight and the butt end cut point of the 12 weight with the Flex Zap and pull the 11 weight core into the 12 weight line. Pull the core through until the two butt ends of line meet; at this point you will probably have pulled the loop of floss out of the line coating and the frayed section of the core along with it. Coat the frayed section with a little more glue right at the point where it exits the line. If you neglect to do this, the splice will have a weak point where the needle exited the line coating. ´Pulling the core is the toughest part of the procedure, and it may take a few times to perfect it, so I suggest that you practice on some throwaway line sections first before attempting the real thing. If you are having difficulty, make sure that the end of the Dacron is really frayed out well so that you could actually count the thread ends of the core if you were so inclined. Also, the center of the 12 weight needs to be hollowed out really well. Don´t worry too much about overdoing it the Flex Zap tends to fill any gaps. To make certain of your splice, though, always test it by giving it a good strong pull before you reel it up.
9. Once the glue has dried, use the razor to cut the frayed section flush with
the line coating.
10. Go get 'em.