The welded loop is the premade loop that comes on the front and back of most modern fly lines, and a lot of veteran fly fishermen do not trust it. They cut it off and build their own loop by doubling the line over and tying nail knots. In this episode I tested the manufacturer's welded loop against a loop I made myself with nail knots, and the result surprised me. The welded loop was not only stronger than my homemade loop, it was actually stronger than the fly line itself.
Listen now: press play in the player above and follow along.
Yes, and it surprised me. In my test the welded loop on a Cortland Precision fly line was not only stronger than the loop I built myself with nail knots, it was actually stronger than the line. The line broke before the welded loop showed any compromise at all. So if you have been cutting the welded loops off your fly lines because you do not trust them, my test says you can have full confidence in a quality manufacturer's welded loop.
Most modern fly lines, like the Cortland Precision I tested, come with a premade loop welded into both the front and the back. The loop lets you make a fast loop-to-loop connection to your backing on the back end, or to your leader on the front end. It saves you from tying knots in slick fly line and gives you a clean, quick connection you can swap in seconds without rerigging the whole line.
You double the fly line over on itself to form a loop, then lock it in place by tying a series of nail knots over the doubled section. It is best to tie those nail knots with a Tie-Fast nail knot tool, which is a simple folded piece of aluminum and one of the cheapest pieces of fishing gear you can buy. If you are not great at nail knots or you want a perfect one every time, that tool is highly suggested.
My homemade loop did not actually break. What happened is the loop pulled out of the nail knots and slipped, even though I pulled about as hard as I would in a real rigging situation. I could probably have tightened those nail knots down better, but the takeaway is that a slipped loop fails just as surely as a broken one. The welded loop, by contrast, did not slip and held past the breaking point of the line.
Based on this test, no. A lot of fly fishermen who have been at it a while cut these loops off because they say they have never lost a tarpon doing it the old way, so they are not going to start trusting the new loops now. But the machine showed the welded loop was stronger than the line itself, so cutting it off and replacing it with a homemade loop actually gave me a weaker connection, not a stronger one.
I have broken and tested a huge range of knots and connections on the Tom Rowland Podcast, and I keep all of those results in a free knot guide. You can download it at tomrowlandpodcast.com and compare breaking strengths side by side. It is the fastest way to decide which knot or loop connection to trust before your next trip instead of guessing at the vise.
This is one of those arguments that has been going on in fly fishing for years. The new lines come with welded loops, and a whole generation of anglers refuses to trust them, cutting them off and tying their own. I did not want opinions, I wanted a number, so I rigged the manufacturer's welded loop against a loop I built with nail knots and pulled them both. What I found changed how I think about it. I walk through the whole test in the episode, so press play in the player above.
When the welded loop sample failed, it did not fail at the loop at all. The line broke down in the running line and the loop stayed perfectly intact, which means that loop is stronger than the line it is built into. My homemade loop told a different story, it slipped out of the nail knots rather than breaking. Seeing both side by side made the lesson obvious. I explain exactly what that means for your rigging in the episode, so press play in the player above and follow along.
Here are the steps I walk through in this How 2 Tuesday. I cover the details in the episode, so press play in the player above and follow along.
I unpack each of these in the episode. Press play in the player above.
I went into this expecting my hand-tied loop to win, and it did not. The manufacturer's welded loop on a quality fly line proved stronger than the line itself, while my nail knot loop slipped under hard tension.
The lesson for me is simple: trust a good welded loop, and if you do build your own, seat those nail knots harder than you think you need to. Press play in the player above for the full test.
welded loop · nail knot · Cortland Precision fly line · Tie-Fast nail knot tool · fly line backing · loop-to-loop connection · Danco · Tom Rowland Podcast · How 2 Tuesday
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.
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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