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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