Whipping a Loop in Fly Line with Double Nail Knots: How Strong Is It?

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Episode Show Notes

Whipping a loop in a fly line means building your own loop on the end of the line by doubling it over and securing it with nail knots, so you have a loop-to-loop connection even when the line has none. On this How 2 Tuesday I show you how to whip a loop using double nail knots and the Tie Fast knot tool, then test how strong that homemade loop really is against the line.

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

Frequently Asked Questions

How do you whip a loop in a fly line?

You double the fly line back over itself to form a loop, then secure it with nail knots tied in 20-pound mono or fluorocarbon. I use the Tie Fast knot tool: put the doubled line in the tool, lay your mono under your thumb, wrap back toward your thumb seven to nine times, run the tag through the gap the tool leaves, and roll it off to form a perfect nail knot. I tie a second nail knot just below the first for a double.

How strong is a loop whipped with double nail knots?

The loop I created broke at 39.81 pounds, which was a little disappointing, I thought it would be stronger. It did not actually break, though, the loop slipped out of the nail knots. Still, 39.81 pounds is more pressure than you will put on a tarpon with 20-pound class tippet, so it is strong enough and a good connection for that use.

What is the Tie Fast knot tool?

The Tie Fast knot tool is a nail knot tying tool, a simple folded piece of aluminum that is incredibly cheap and incredibly efficient. Even though I could probably tie a nail knot without it, I do not really want to. This thing is gold. Anybody tying a nail knot for any reason might want to invest in one, because it makes a really good knot every time.

How many nail knots should you use to whip a loop?

I like to tie two nail knots on the loop, a double. After the first one, I cut the tag, then tie a second nail knot just below it, pulling it back slightly to leave a small gap between the two as a little safety measure. Some people put three, but I think that is overkill. Two nail knots form the loop well.

Why did the whipped loop slip instead of break?

When I tested it, the loop pulled out of the nail knots rather than breaking the line, which tells me I may have been able to tighten the knots down a little better. It is worth knowing that the failure mode here is slippage, not breakage, so seating those nail knots tightly is what gives you the most secure homemade loop.

Is a whipped loop strong enough for tarpon?

For tarpon, yes. At 39.81 pounds the whipped loop holds far more than you will ever exert on a tarpon with 20-pound class tippet. Anglers chasing much heavier fish on heavy fly line, like arapaima, would want the strongest possible connection, but for standard tarpon fishing this loop is a good, reliable choice.

Why You Might Need to Whip Your Own Loop

Most fly lines come with a loop on the end, but sometimes one does not, or your line gets cut, and you need to build the connection yourself. Whipping a loop with nail knots is how you do it. I explain when this comes up in the episode, so press play in the player above.

How to Whip a Loop with Double Nail Knots

  1. Pull off 20-pound mono. Pull off a piece of 20-pound monofilament or fluorocarbon, like Daiwa J-Fluoro, to tie the nail knots.
  2. Double the fly line into the tool. Turn the fly line over to create a loop and seat it in the Tie Fast knot tool with your thumb on the tool's pad.
  3. Wrap the first nail knot. Lay the mono under your thumb, wrap back toward your thumb seven to nine times, keeping extra on both ends.
  4. Roll it off and seat it. Run the tag end through the gap the tool leaves, roll it off the tool to form the nail knot, and pull it down tight.
  5. Tie a second nail knot. Tie a second nail knot just below the first, leaving a small gap as a safety measure, then trim the tags and the fly line close.

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

Why the Tie Fast Tool Is Worth It

The Tie Fast knot tool is one of the cheapest pieces of fishing gear you can buy, a simple folded piece of aluminum, but it makes a perfect nail knot every time. I could tie a nail knot without it, but I would rather not. I show exactly how I use it in the episode, so press play in the player above.

What the 39.81-Pound Result Means

My whipped loop broke at 39.81 pounds, and it slipped out of the nail knots rather than breaking, which means I could have tightened them down better. Still plenty for tarpon on 20-pound tippet. I get into the tradeoffs in the episode, so press play in the player above.

Final Thoughts From Me

Whipping a loop with double nail knots gives you a solid, fishable connection when your fly line has no loop of its own. Seat those nail knots tight and you have a loop that holds for tarpon and most fly fishing.

If you chase truly heavy fish you may want something stronger, but for the rest of us this is a great skill. Grab the free knot guide at tomrowlandpodcast.com to compare. 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

Whipping a loop · nail knot · Tie Fast knot tool · fly line · Daiwa J-Fluoro · tarpon · arapaima · 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 882: Tom Rowland (How 2 Tuesday)

In this episode: whipping a loop in a fly line with double nail knots, the Tie Fast knot tyer, the 39.81-pound break test where the loop slipped out, and why it’s still plenty for tarpon on 20-pound class tippet — in the exact words spoken.

00:00 · Cold Open

Tom Rowland: If you want everything you need to take care of your boat, StarBright's got the solution. It's called boat care in a bucket. That's right. One three and a half gallon bucket packed with essentials, vinyl bright, deck cleaner, marine polish, a wash mitt, hull cleaner, and boat wash. That one kit will keep any boat clean and protected, but that's just the start. I also use StarBright's salt off, which is incredible for rinsing salt off after a day on the water. Their brushes and cleaning products work just as well on your RV and patio furniture and anything else that lives outside. It is a company that gives back. That's one of the things that I really like about StarBright. StarBright supports marine conservation through Project Sea Safe, and that means a lot to me personally. You're getting performance and purpose. Visit starbrite.com. That's starbrite.com, and get your boat dialed in for the season. From The Seychelles to The Keys, I trust Nikon binoculars to find fish fast. Visit nikonusa.com and upgrade your line of sight. I thought I was covered, but I wasn't. HH Insurance showed me that my old policy did not cover The Bahamas or nighttime navigation, two major gaps that could have cost me a lot. Jake and Landon fixed it fast. They know charter policies better than anyone I've ever worked with. Call (727) 498-5551 or visit hhinsgroup.com and tell them Tom Roland sent you. Trusted enough to go with me to The Seychelles, my Danco pliers are a staple in my kit. Check out dancopliers.com and build yours today.

01:36 · How 2 Tuesday: The Best Fly Line Connection When There’s No Loop

Tom Rowland: What's going on, everybody? It is Tom Roland podcast, and this is how to Tuesday brought to you by Danco. Today, we're talking about fly fishing, fly lines in particular, how to make the best connection between your fly line and either your backing or your leader. And so many lines will come with a loop on the end. Sometimes you'll find one that does not or your line could get cut or something else could happen to it to where you do not have the loop on the end. And so I'm gonna show you today exactly how you would do that yourself by what's called whipping a loop in the fly line. We're gonna do this with nail knots.

02:13 · The Tie Fast Knot Tyer — the Cheap Tool That’s Gold

Tom Rowland: And if you want to, tie the best nail knots, there is an incredibly cheap and incredibly efficient tool. Tool. This is called the Tie Fast Knot Tire. It's a nail knot tying tool. And, even though I could probably tie a nail knot without it, I don't really want to. This thing is gold. Every fly fisherman, anybody tying a nail knot for any reason might want to invest in these, in one of these tools. They're very cheap, very inexpensive, but very, very efficient.

02:44 · Setting Up: 20-Pound Fluoro and the Doubled-Over Fly Line

Tom Rowland: So when you're gonna whip a loop in the fly line, you need the fly line, you need the tie fast knot tire, and I like to do it with 20 pound monofilament or fluorocarbon. Today, we're gonna use the Daiwa J Fluoro, and we're going to just pull off a nice piece of that. We will just turn the fly line over. So you'll create your loop like that. And you'll have your fast knot tire. And you're going to put that right in the knot tire like that. Then the knot tire has a little tool right here for your thumb. Your thumb goes right on top of that. And now you have the loop in there.

03:25 · Wrapping the First Nail Knot, Seven to Nine Turns

Tom Rowland: Next, you're gonna take your piece of monofilament. You're gonna leave extra on both ends, and I'm gonna put that right under and pinch it with my thumb. Okay? So now that is gonna come down right in to the top fast knot tire, this little, this little gap right here. And I'm going to start wrapping backwards towards my thumb. One, two. You can do it as many times as you want. Seven or eight, nine times. And this is why you wanna keep extra on both ends here. Now I'm gonna put my finger right on the edge of it, and go up to the tag end here, and I'm gonna put it right through this open gap that the tie fast knot tire leaves. And it is very convenient.

04:20 · Rolling It Off the Tool and Pulling Down Tight

Tom Rowland: K. So now I have it pinched with my thumb, and I have the extra over here, and I just use my finger to start to get it to roll down. And I'll pull it right off of the knot tire, and it will form a perfect nail knot right there. And the reason I left some on the other end is so that I can actually tie it down. If you don't have enough here, you'll kinda be sorry. So I will pull it around my hands like this and pull down tight, and you get a perfect nail knot every time. K. So I want enough to where I can wrap it around my fingers on both sides, and that is basically your loop.

05:05 · Tying the Second Nail Knot for a Double

Tom Rowland: What I like to do is tie another one. So I'll show you how to do it again. I'll cut the tag end off the other side. So if we wanted to see this done again, what we'll do is we're gonna tie another nail knot just below this one. So there's one, and I'll tie a double, put two nail knots on this loop. So I put the whole loop through there, pinch right there, take my 20 pound, pinch it on my thumb, put it in the little gauge there, and and wrap it without going over itself seven, eight, nine times, however you want. Put your finger on the edge, run the line back through the knot tire, and it will just pull right off and make a perfect nail knot.

06:06 · A Little Gap for Safety, Then Trim Everything Close

Tom Rowland: If I want it real close, I can leave it there. I'm gonna pull pull it back just a little bit and leave a gap between the two. A little safety measure. So now I have two nail knots that form the loop. Just trim off the pieces, the tag ends. And then I'm also gonna trim the fly line very close. Very close right there. You want a smooth connection. K. So now you have a loop. One nail knot, two nail knots. Some people might put three. That's overkill, I think.

07:01 · The Break Test: 39.81 Pounds and a Surprising Slip

Tom Rowland: So now we're gonna test it and see how strong it is. So the loop that I created broke at 39.81 pounds, which is a little disappointing. I thought it would be a little stronger, but it slipped out. The the loop actually slipped out of the nail knots. So 39.81 pounds is certainly more pressure than we're gonna put on a tarpon when we're using 20 pound class tippet. So turns out that it's strong enough, and it's a good connection. But I was disappointed at how it pulled out.

07:39 · Arapaima, Tarpon Tippet, and the Free Knot Guide

Tom Rowland: Some people fish for other fish, with much heavier line like arapaima. I know that's an issue. People are trying to use the heaviest fly line line that they can, so the strongest possible connection would be interesting for them. But for tarpon, this is enough. If you wanna see how this knot compares to all the other knots that we test on the Tom Roland podcast, you can go to tomrolandpodcast.com, and you can download the free knot guide that shows you all of the breaking strengths of all the knots we've tied. And then you can pick the knot that you want to tie for whatever breaking strength you're looking for. You can find the best knot. Alright. That's it for today. We'll see you next week.

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