I have tied similar flies from size 12 to size 24. CDC fibers are spun into chenille rope and wrapped like hackle.

You will need a tying thread that splits easily, Danville works,UNI thread does not. Tie into the hook and attach a tail and dubbed body with foam wing post, just as you would for a feather hackled fly.

Select 2-3 similar length CDC feathers, stack them and preen the fibers out at right angles to the stem. The length and number of feathers need to vary with the hook size. For size 8- and smaller a single CDC feather is enough. 3 or more feathers for a bushy size 12.

Only the fibers on one side of the center stem are used in each fly. So each stack of CDC feathers will make 2 sections of CDC hackle rope.

Pull out about 3" of extra thread from your bobbin. Stroke the tying thread with a needle or the back of your thumb nail to flatten it into a ribbon, pierce the flattened thread with a needle and divide it into two equal strands.

Place the prepared CDC feathers between the split threads. Align the feather so the thread is parallel to the feather stems, approx. halfway between the center stems and the fiber tips. Apply tension to the thread to trap the fibers in place. With a sharp scissors cut along the feahter stem and release the fibers. Save the uncut side for the next fly. You should end up with a clump of neatly aligned CDC fibers that are trapped in the thread.

Trim the tips of the fibers even, then spin the bobbin to tightly twist the thread. The CDC fibers twist into a bottle brush shaped 'chenille' rope.

Wrap this spun thread like any feather hackle around the post and tie off. Brushing the CDC fibers to point back before each wrap helps avoid crushing old layers. 2-3 sparse turns is best, depending on how dense you made your hackle rope.

Trim any loose or stray CDC fibers to size.