I experimented with this for many years in the pacific northwest for steelhead fishing. I came up with my own approach in the 80's which I still favor to this day.
Strip the coating to the core for an inch or so. You can use a precision wire stripper or nail polish remover.
Use a pc of braided nylon long enough to go down over the coating that still remains, slinky the core inside the braided line.
Note - use a real braided line not the cheap stuff they sell in small pieces in a bag at flyshops. I have spools of cortland 30# and 50# braid for this purpose.
Fold into a loop. If using heavy line, shave a taper into the coating on the side where the loop meets.
Using 10# maxima and a doll needle, secure the loop with a floating nail knot.
Trim flush with nail clippers and coat with aquaseal thinned with cotol for best results.
I have pulled tips in half but never broke one of these loops in decades of steelhead fishing.
Hope it works out for you.
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