A friend introduced me to UV knot glue on the stream years ago, and I haven’t looked back. As the name suggests, UV glue is great for making your knots stronger; just put a dab on a knot, expose it to sunlight or a UV light source for 15-60 seconds, and you’re good to go. Your knot is now super-strong and will slip right on through your guides. The final cured substance is pliable and won’t break or crumble off your knots. I haven’t formally strength-tested the coated knots, but I have noticed that when I break off, the break is always somewhere else in the line or leader, not at the coated knots.
I primarily use UV Knot Sense for line-to-leader connections on both my fly and conventional outfits, but it’s great for securing any knot in your setup. Additionally, it has a number of secondary applications. I’ve used it to repair my leaking waders in a pinch (Loon also makes a UV wader repair product), fix unraveling bluefish-bitten flies and bucktails, and even close up a small, persistently bleeding cut on the back of my hand. There are numerous other UV-cure products that are great for fly tying (ClearCure Goo), but that’s another article altogether.
Loon also makes a UV lamp that allows you to use Knot Sense on overcast days, at night, or anywhere you don’t have access to direct sunlight. My only experience with the lamp was in trying to set some UV Knot Sense over a pair of leaking waders. A friend just so happened to have one, and it saved our day. We were miles from civilization on an overcast day, and we didn’t have any conventional silicone-based sealant. A liberal application of UV Knot Sense, a few seconds of UV light, and I was back in business.
Still holding strong after two yrs.
The Loon lamp is rather expensive at approximately $35, however, and I will readily admit that I don’t own one. If I really thought a devoted portable UV lamp were essential for setting UV glue, there are a number of sources that sell them for non-fishing purposes (nail polish curing, dental, etc.), at lower prices. Beware: a less powerful lamp may not cure the glue all the way; I haven’t experimented with them.
UV Knot Sense and UV Knot Sealer retail for about $8.50 for a 1/2 oz. tube.