The Nail Knot with a Lock: Tie It and Test It

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Episode Show Notes

The nail knot with a lock is a fly line to leader connection where you tie a nail knot and then add a figure-eight lock behind it, so the knot will not slip when you are fighting big fish. On this How 2 Tuesday I tie the nail knot with a lock for fishing big fish like tarpon, then test it. A plain nail knot can slip under heavy pressure, and the lock is meant to stop that. Here is how to tie it and what the test showed.

Listen now: press play in the player above and follow along.

Frequently Asked Questions

What is a nail knot with a lock?

A nail knot with a lock is a standard nail knot connecting your leader to the fly line, with a figure-eight knot added behind it as a lock. When you are fighting really big fish, a plain nail knot will oftentimes slip, so the lock holds it in place. The lock is the figure eight, and I use a figure eight rather than an overhand because the figure eight will not come untied.

How strong is the nail knot with a lock?

In my test the nail knot with a lock broke at 28.58 pounds, which was slightly disappointing, and it broke within the knot itself. That is the 50-pound butt section to an 11-weight fly line. It is more than you will exert on a tarpon, and it is a slightly smoother connection through the guides, but the loop-to-loop with the welded loop is much stronger.

Why use a figure eight for the lock instead of an overhand?

I use a figure eight for the lock because the figure eight will not come untied. Some people just do an overhand there, but I have had overhands come untied, so I started doing a figure eight a long time ago. You tie it tight up against the nail knot lock, seat it, then trim, and you have a secure lock that stays put.

Why tie a nail knot with a lock instead of a loop-to-loop?

The loop-to-loop with the manufacturer's welded loop is stronger, but when you tie a loop in the leader and connect it loop-to-loop, that knot can stick going in and out of the guides. The nail knot with a lock gives you a smoother connection that slides through the guides better. It is the dilemma: a little less strength for a cleaner pass through the rod.

What line should you use for the butt section?

There is no set pound test for the butt section of your leader, but you want it similar in diameter and stiffness to your fly line so the energy transfers smoothly. I used 50-pound J-Fluoro to an 11-weight, 50-pound fly line, which is about the same, then tapered down from there for a nice smooth transfer of energy on the cast.

When should you choose this knot?

This may be the better knot in certain situations, where the stronger loop-to-loop causes problems going in and out of the guide. That is for you to decide based on your setup. I keep a free knot guide at tomrowlandpodcast.com with this knot and every other one I have tested so you can pick the one that works best for you.

Why I Tie This Knot for Big Fish

When you are fly fishing for tarpon or offshore fish you really have to pull on, every connection from the backing to the fly matters. A plain nail knot can slip under that kind of load, so I add the lock. I explain where it fits in the episode, so press play in the player above.

How to Tie the Nail Knot with a Lock

  1. Set up the tool and line. Use the Tie Fast knot tool and 50-pound J-Fluoro for the butt section, matched in diameter and stiffness to your fly line.
  2. Wrap the nail knot. Put the line in the tool's gap, thumb on the pad, and wrap back toward your thumb six, seven, even nine times.
  3. Run the line and seat it. Put the fly line through the knot, ease the line off the tool to form a perfect nail knot, then snug it down leaving extra line.
  4. Add the figure-eight lock. Tie a figure eight behind the nail knot, going around and behind twice, and seat it tight up against the nail knot lock.
  5. Tighten and trim. Pull the lock down tight without pulling the tag, then trim the tag ends close for a smooth connection through the guides.

I walk through each of these in the episode. Press play in the player above.

Why the Figure Eight Beats the Overhand

The lock is a figure eight, not an overhand, because I have had overhands come untied on me. The figure eight stays put. That small choice is the difference between a lock that holds and one that quietly fails. I show how I seat it in the episode, so press play in the player above.

The Tradeoff Behind the 28.58 Pounds

It broke at 28.58 pounds within the knot, less than the welded loop's loop-to-loop, but it runs through the guides much more smoothly. That is the real dilemma, strength versus a clean pass through the rod. I break it down in the episode, so press play in the player above.

Final Thoughts From Me

The nail knot with a lock is not the strongest connection on the tester, but it is smooth through the guides and the figure-eight lock keeps it from slipping. In the right situation it beats the stronger option that hangs up in your guides.

That is exactly why I tie and test so many of these, so you can pick the best knot for your setup. Grab the free knot guide at tomrowlandpodcast.com. Press play in the player above.

More How 2 Tuesday Tutorials

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.

People & Topics Mentioned

Nail knot with a lock · nail knot · figure-eight lock · fly line · J-Fluoro · Tie Fast knot tool · tarpon · welded loop · loop-to-loop · Danco pliers · How 2 Tuesday · Saltwater Experience

About Me

I'm 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's 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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Episode Transcript

Transcript

Tom Rowland Podcast — Episode 886: Tom Rowland (How 2 Tuesday)

In this episode: why a plain nail knot slips on really big fish, tying the nail knot with a lock in 50 pound J fluoro with the tie-fast knot tyer, the figure eight lock that won't come untied, a break test at 28.58 pounds, and the dilemma between strength and a smooth connection through the guides — in the exact words spoken.

00:00 · Cold Open

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01:36 · Tie It and Test It: The Nail Knot with a Lock

Tom Rowland: Some people prefer to tie something called the nail knot with a lock or just a simple nail knot. But when you're fighting these really big fish, oftentimes, a nail knot will slip. So I'm gonna show you the nail knot with a lock today. We're gonna tie that and then we're gonna test it. What's going on everybody?

01:54 · How 2 Tuesday: Connections for Tarpon and Big Fish

Tom Rowland: It's how to Tuesday on the Tom Rowland Podcast brought to you by Danco. And today, we're talking about fly fishing. We're talking about fly fishing for big fish, like tarpon, offshore fishing for for fish that you're really gonna need to pull on. It's very important that you have really good connections all the way from the fly line. Well, really all the way from the backing to the fly line, from the fly line to the leader and from the leader to the fly so that you can put maximum pressure on these fish and actually have a chance of getting them in.

02:23 · Welded Loops and a Double Overhand in 50 Pound J-Fluoro

Tom Rowland: Most manufacturers these days are putting a welded loop on the end of their fly line, which is what I have right here. And then in order to tie the leader onto that, we would tie a loop in the leader. This is 50 pound J fluoro, and I have a double overhand loop here. Here, and I like this loop because the tag end is parallel to the to the running line. There are many other knots that you can tie where the tag end like a perfection loop where the tag end would be at a right angle.

02:54 · The Problem: Loops That Stick in the Guides

Tom Rowland: And that is going to be a problem when you're bringing the leader in and out of the guides because that little tag end is gonna stick in the guides. Even this tag end and even this knot will stick in the guides. So while the manufacturer's loop is perfectly smooth and an absolute great way to finish a fly line, when you tie this other loop onto the end, it can have trouble going through the guide. So some people prefer to tie something called a nail knot with a lock or just a simple nail knot. But when you're fighting these really big fish, oftentimes, a nail knot will slip.

03:32 · Setting Up: 50 Pound J-Fluoro to an 11-Weight Fly Line

Tom Rowland: So I'm gonna show you the nail knot with a lock today. We're gonna tie that, and then we're gonna test it. So we're gonna tie the nail knot with a lock. We're gonna do it with 50 pound j fluoro, and we're gonna attach it to a fly line here. This is an 11 weight fly line, 50 pound line.

Tom Rowland: There's no real, set number of pound tests that you would want for your for your, your butt section of your leader, but you want it to be similar in diameter and also similar in, in stiffness to your fly line. So this is about the same, and then we're going to taper down from there and that's gonna allow for a nice smooth transfer of the energy. So you only need one thing when you're gonna tie this knot really. And that's this simple tie tie fast knot tyer. We're gonna take our 50 pound test.

04:25 · The Tie-Fast Tool: Wrapping Six, Seven, Even Nine Turns

Tom Rowland: And before we even mess with the, with the fly line at all, we're gonna put this right into this gap right here, put our finger or thumb on this little place that's set made for it. And then we're going to wrap around and back towards our thumb. I like to do it about six or seven, even up to nine times. Okay. So once I have that, I put my finger on the end so it doesn't unroll and I put this tag end back through the whole knot.

05:04 · Forming the Nail Knot Before You Touch the Fly Line

Tom Rowland: That's what's so great about this tie knot, knot knot tyer is that you can go ahead and create the knot before you even mess with the line. Okay. So now I'm gonna take the line and I'm gonna put it right in in through the knot. I'll just run it up in there, and I'm going to just ease off of the ease this line off of the knot tyer, and it is going to form a perfect nail knot right there. K.

Tom Rowland: So now we're done with the knot tyer, and I have the nail knot on the line. I want extra line like this. So I'm just gonna give this nail knot just a little bit of pull down. Okay. So if I really wanted to, I could just really pull on both ends of this nail knot, and that would be a nail knot.

05:58 · Adding the Lock: A Figure Eight for Extra Security

Tom Rowland: I want a nail knot with with a lock. So what I'm going to do for a little extra security, I'm going to tie an overhand right here. So I'm going to go around and behind twice. Okay. Then I'm going to put this through here, and this is gonna form an overhand or, I mean, a figure eight.

Tom Rowland: So you see how that formed a figure eight? I will tie that down. I'm gonna tighten purposely did not pull it down. I purposefully did not pull it down as tight as it could go because I wanted to get it to this point right here. I want it tight up against the nail knot lock.

06:56 · Seating It Tight Against the Nail Knot

Tom Rowland: And then once I'm satisfied with where that knot is, I could take a wrap with my fingers and pull this down real tight. K? And then I'm going to also once I've got it tight, I'm gonna now pull without pulling on that tag end. So now I have a nail knot with a lock. K.

07:17 · Why a Figure Eight Instead of an Overhand

Tom Rowland: The lock is the figure eight. Some people will just do an overhand there, but the figure eight won't come untied. I've had overhands come untied, so I started doing a figure eight a long time ago. Okay. So now all we'll do is trim the tag ends tight and close.

07:39 · Trim It, Test It: Broke at 28.58 Pounds

Tom Rowland: You could put some Zap-A-Gap or some other thing to create kind of a bubble over the top of this, but that is pretty smooth. It's gonna go in and out of the guides better than the loop to loop, in my opinion. So now we'll test it. So the nail knot with a lock broke at 28.58 pounds, which is slightly disappointing. It broke within the knot.

08:10 · The Dilemma: Strength vs. Smooth Through the Guides

Tom Rowland: This is the, this is the butt section, 50 pound butt section to the 11 weight fly line. We had a nail knot to a, to a lock and it broke within this knot right here. So at 28 pounds. So while that is more than we are going to be exerting on the tarpon itself, and it is slightly smoother connection, the loop to loop connection with the smoother connection. The loop to loop connection with the manufacturer's welded loop is much stronger. But you have, you have an issue with the knot going in and out of the, the guide. So that's the dilemma. And that's why we have so many of these different knots that we're always trying and testing and making sure that we have the best knot for the situation.

08:59 · Pick What Works for Your Setup: The Free Knot Guide

Tom Rowland: This may be, in certain situations, a better knot than the stronger that causes problems going in and out of the guide. So that's for you to decide. You can go to tomrowlandpodcast.com. We've put together a free knot guide that has this knot and all the other knots that we have tied and tested so that you can pick the knot that works best for your setup. That's the way.

Tom Rowland: It's the one that works best for your setup. You can take all the test results that we've had and you can decide for yourself. Go to tomrowlandpodcast.com and download that free knot guide. We'll see you back next week to test something else.

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