Manufacturer's Welded Loop vs. The Nail Knot Loop: Which Is Stronger?

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Episode Show Notes

This is a head-to-head fly line strength test between the manufacturer's welded loop and a loop you make yourself with nail knots, to settle which connection is actually stronger. On this How 2 Tuesday I put the factory welded loop against a homemade nail-knot loop on the same fly line. A lot of veteran fly fishermen cut the welded loop off and tie their own, so I tested both to see whether that tradition holds up.

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

Frequently Asked Questions

Which is stronger, a welded loop or a nail knot loop?

The manufacturer's welded loop won, and it surprised me. The welded loop was not only stronger than the homemade nail-knot loop, it was actually stronger than the fly line itself. When I pulled it, the line broke down in the line while the welded loop stayed perfectly intact, so I have 100 percent confidence in it.

Why do fly fishermen cut off the welded loop?

A lot of fly fishermen who have been at it a while just do not trust the manufacturer's loops. They think, I have never lost a tarpon the other way, so I am not going to start now, and they cut the welded loop off and make their own loop with nail knots. This test was about whether that long-held habit actually produces a stronger connection.

How did the nail knot loop fail?

When I tested the loop I made with nail knots, it did not break, the loop actually pulled out of the nail knots. It slipped. I pulled pretty hard, about as hard as I would in a rigging situation, and it still slipped out. So maybe I could have tightened the nail knots down a little better, but the welded loop did not slip at all.

How do you make your own loop with nail knots?

You double the fly line over and then tie nail knots to hold the loop. It is best to tie them with a Tie Fast nail knot tool, probably the cheapest piece of fishing gear you can buy, a simple folded piece of aluminum that makes a really good knot. If you are not great at nail knots or just want a perfect one every time, that tool is highly suggested.

Is the welded loop strong enough for tarpon?

Absolutely. The welded loop broke in the line rather than at the loop, which means it is stronger than the line, so I have 100 percent confidence in it. With no compromise on the loop whatsoever, it handles tarpon and more. For most fly fishing connections, trusting the factory welded loop is the stronger choice.

Where can I compare these loop connections?

I keep a free knot guide at tomrowlandpodcast.com that shows this connection plus every other knot I have ever tested on the podcast, with the breaking strength of each one. It lets you pick the connection you want in your setup based on real numbers, not tradition or guesswork.

Why I Ran This Test

So many veteran fly fishermen cut the factory loop off and tie their own with nail knots, trusting tradition over the manufacturer. I wanted to put both on the tester and see if that habit actually buys you a stronger connection. I set it up in the episode, so press play in the player above.

How to Compare the Welded Loop and Nail Knot Loop

  1. Identify the welded loop. Start with the manufacturer's pre-made welded loop on the front and back of a new fly line, like a Cortland Precision.
  2. Make a nail-knot loop to compare. To make your own loop, double over the line and tie nail knots, ideally with a Tie Fast nail knot tool for a clean knot every time.
  3. Set up the loop-to-loop. Plan your loop-to-loop connection, a bimini twist to your backing or another loop knot to your leader.
  4. Test both under load. Load each loop to failure to see which holds, the welded loop or the homemade nail-knot loop.
  5. Trust the welded loop. Use the welded loop with confidence, since it broke in the line while the nail-knot loop slipped out.

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

The Result That Surprised Me

The welded loop did not just beat my homemade loop, it was stronger than the fly line itself, breaking down in the line with no compromise on the loop at all. That changed how I think about the factory loop. I break it down in the episode, so press play in the player above.

Why the Nail Knot Loop Slipped

My nail-knot loop did not break, it pulled out of the nail knots even though I pulled as hard as I would when rigging. That slippage is the lesson: a homemade loop is only as good as how tight you seat those knots. I explain in the episode, so press play in the player above.

Final Thoughts From Me

The data flipped my expectation. On this line the manufacturer's welded loop was stronger than the line and stronger than the loop I tied myself, with zero slip.

Tradition is not always right, and that is exactly why I test these things. Grab the free knot guide at tomrowlandpodcast.com to compare every connection. 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

Welded loop · nail knot loop · fly line · Cortland Precision · Tie Fast knot tool · bimini twist · tarpon · 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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