I have been fishing this pattern for some time now and it never ceases to amaze me how something so simple and quick to tie can be so effective. On my recent Rhodes trip, I fished it almost exclusively when nymphing and it worked exceptionally well on all the rivers I fished. You need to tie it with a tungsten bead otherwise it will fish as an emerger :D Even with a tungsten bead, you need to give it a couple of squeezes underwater/add a bit of saliva to it/or treat it with a sinkant in order to get it to sink initially. When I first started fishing it, I thought that the orange bead must be the reason for it's effectiveness. While this does play a part, on my Rhodes trip I had several occasions when the fly had taken so many fish it was in tatters - just a bead and a bit of black cotton. I tried fishing the pattern like this in several runs without a single take. As soon as I changed to a fresh fly and fished the identical run I would get takes. I repeated this enough times to believe that the CDC does play a very important role in the patterns effectiveness. The CDC obviously provides a lot of natural movement which I suspect is one of the key triggers. Once you have the hook placed in the vise, it typically takes less than a minute to tie the fly - very appealing quality when you want to knock out 5 or 10 before fishing.
Here are the video sequences (thanks to Wiets) on tying this fly and the slightly longer but more durable version:
http://www.weizter.org/Images/Video/DLampertCDCNymphS.html
http://www.weizter.org/Images/Video/...CNymphIIS.html
Hook: Grip 12003 #14 or equivalent
Bead: 2mm Fluoro Orange Tungsten
Thread: Gordon Griffiths Sheer Thread (Colour to match body)
Tail, abdomen & thorax: CDC Feather (Colour of choice)
Step1
Add bead to hook and place in vise
http://i270.photobucket.com/albums/j...rout/step1.jpg
Step2
Run thread down to bend of hook
http://i270.photobucket.com/albums/j...rout/step2.jpg
Step3
Stroke fibres towards tip of CDC feather and tie in tips as tail. Length of tail should be around shank length. Normally around 4 wraps will secure the feather.
http://i270.photobucket.com/albums/j...rout/step3.jpg
Step4
Leaving the thread at the tail tie in point, grab the end of the feather with your fingers or hackle pliers and simply wind it around the shank towards the eye of the hook forming a tapered body. When you get to the thorax section, make your wraps a bit closer together in order to bulk up the thorax a bit. At this stage you should start getting some of the longer fibres which will allow a soft hackle collar behind the bead. Holding the end of the feather in your right hand, run the thread over the body to strengthen it.
http://i270.photobucket.com/albums/j...rout/step4.jpg
Step5
Trim the end of the feather off and whip finish.
http://i270.photobucket.com/albums/j...rout/step5.jpg