soft hackle abdomen materials
The Krystal Flash works well and provides a lot of color/flash but, to be honest, it's not very durable. As a result, very fine wire counter-wrapped or head cement will keep it together longer. My normal routine for tying with KF is to tie it in at the thorax, wrap it down to the bend, coat the wraps with head cement, then wrap over the previos wraps (now saturated with cement) back to the tie-in point. It is about as bullet-proof as it can be made.
As for other body materials, I really like using the traditional old Pearsall's silk as it ties so nicely and keeps the bodies very slim. Lately I have also been tinkering with DMC floss. It is mercerized cotton embroidery floss available in about 350+ colors and is really, really inexpensive (about $0.24/skein). It darkens up like silk and lends itself nicely to weaving.
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