Numerous fly-tying applications call for feathers to have the barbs on one side of the rachis (feather shaft) folded back essentially parallel to the barbs on the opposite side. This includes flymphs, soft hackles, body and throat hackles on steelhead and salmon flies, palmered hackle on Wooly Buggers, and many more. The purpose of using a folded hackle is to allow the barbs to sweep toward the hook bend, or in the case of a Sakasa Kebari (“reverse [hackle] fly”), to make the barbs sweep toward the hook eye.
There are several methods. One may result in a similar appearance to a folded feather but is not a folded feather at all, and that is to strip off one side of the feather rather than fold it. I do not recommend this since if more equal length of resulting barb tips is preferred, due to the diminishing length of barbs as the feather tip is approached on a typical soft hackle feather, the result may be a fly having barbs longer on one side than the other.
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