The blood knot and the triple surgeon's knot are two ways to join sections of a tapered fly fishing leader, and anglers argue about which is stronger around every campfire. In this How 2 Tuesday I take Knot Wars into fly fishing ahead of an Alaska trip, tying both in Orvis SuperStrong Plus tippet joining 3X to 4X, and breaking each on my NexTech force tester. I like the blood knot and hoped it would win, but in science you do not hope, you test.
Listen now: press play in the player above and follow along.
The blood knot won, and it was not close. On my retest joining 3X to 4X tippet the blood knot broke at 4.42 pounds and the triple surgeon's knot at 2.52 pounds. That is nearly two extra pounds of drag you could put on a fish with the blood knot. The surgeon's knot lost badly both times I tested it, so for joining leader sections I am sticking with the blood knot.
In my testing it simply broke at a much lower number, about 2.52 pounds versus the blood knot's 4.42 on the same 3X to 4X tippet. On top of being weaker, it does not sit smooth, it kicks up and back down, and it leaves tag ends that catch vegetation in the river. So if you are tying a double or triple surgeon's knot for trout and breaking off a lot of fish, the knot's strength may be the reason why.
I used Orvis SuperStrong Plus nylon tippet, a popular fly fishing tippet, joining 3X to 4X. In tippet terms 3X is about 8.5 pounds and 4X is about 6 pounds, so I was hoping the connection would break above six. SuperStrong has been around a long time, and there is also a fluorocarbon version, but for this test I wanted to use the exact nylon tippet I would fish with.
Fly fishermen rate thin tippet by X instead of pound test, and the higher the X, the smaller and weaker the line. Roughly, 0X is about 14.9 pounds, 2X about 9.8 pounds, 3X about 8.5 pounds, 4X about 6 pounds, and it keeps dropping through 5X, 6X, 7X, and 8X, which is about as thin as human hair. Technical spring creeks call for 7X or 8X, which is why a lot of us end up wearing glasses to thread the fly.
Because it suits the purpose better. The blood knot, also called a barrel knot, comes together clean and smooth so it slides through weeds and through the guides on your rod easily. The surgeon's knot does weird things to the leader and snags vegetation. Even if the surgeon's had tested stronger, I would not use it, because you are not always after the strongest knot, you are after the one that best fits the job.
No. My first round gave strange low numbers, 2.67 and 1.5 pounds, that I did not trust, so I retied fresh line and tested again, which is exactly what you should do. Even my better numbers tell me there is probably a better knot and a better way to tie it out there. A single test is a starting point. Tie fresh, test again, and look for a consistent result before you commit.
Here is how I compared these two tapered-leader knots, and how you can do the same with your own tippet.
I was getting ready for an Alaska trip, chasing trout, salmon, and Dolly Varden along with some offshore halibut and lingcod, and a fly leader is tapered down with knots. That made it the perfect time to settle a debate I have had around many campfires: blood knot or triple surgeon's. I set the whole thing up in the episode, so press play in the player above.
My first round gave numbers so low, 2.67 and 1.5 pounds, that I knew something was off and stopped to retie fresh line. The retest was cleaner: 4.42 for the blood knot and 2.52 for the surgeon's. That is why you never trust a single odd pull. I walk through that whole sequence in the episode, so press play in the player above.
Even though the blood knot won, I make the point that strength is not the only thing. The blood knot sits smooth, slides through the guides, and does not snag weeds, and I would tie it over the surgeon's even if the numbers were reversed. I explain that thinking in the episode, so press play in the player above.
How 2 Tuesday is my weekly series where I break down one fishing skill at a time, from knots and casting to gear, tactics, and the habits that make you a better angler. Watch and listen to every How 2 Tuesday episode from Tom Rowland.
blood knot · barrel knot · triple surgeon's knot · tapered leader · Orvis SuperStrong Plus tippet · 3X tippet · 4X tippet · fluorocarbon tippet · Alaska · trout fishing · salmon · Dolly Varden · NexTech force tester · How 2 Tuesday · Saltwater Experience
I am Tom Rowland, a professional fishing guide based in the Florida Keys, host of the Tom Rowland Podcast, and the longtime host of the Saltwater Experience television show. On the podcast How 2 Tuesday series I break down one practical skill or lesson at a time, from fishing technique and gear to the habits that make you a better angler, in short, focused episodes you can put to use right away.
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