Most fly lines these days already come with welded loops at the ends for the easy attachment of backing and leaders. If you fish as much as I do though, eventually they get worn out and need to be replaced. Most anglers just use a standard albright knot or nail knot to fix this. It works perfectly fine, but I prefer instead to tie my own fly line loops with a fly tying bobbin and thread. Done correctly, it will provide a stronger connection to your leader than the manufacturers welded loops or knots you tie (this is important when fly fishing for big game species). The bright thread that you tie the loop with also works really well as a spotter. It comes in real handy when you're fly fishing and you have conditions where it's hard to keep track of your fly in the water. That bright spot on the end of your fly line provides a quick reference that your fly is a leaders length away. Below are step-by-step instructions for tying your own fly line loops.
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