Raymondo Noordeneer offers us a step by step tutorial to tie his fat double bonktail pattern. Groovy pike fly ! 

In five steps:

Step 1: Determine the length of two pieces small plastic tube, according to your choice of material required in hackle distance. Calculate an extra cm, this is done for two reasons: (1) for your finished head about 5 mm (2) The plastic tube runs thru within another 5 mm, otherwise the finished head will throttling the mylar cord.

Step 2: Secure one plastic tube in the (tube)vice, slightly roughen up the surface and put on your thread.

Step 3: Slide the mylar cord all over the tube, secure it with a half hitch to hold it in place. Put the piece of mylar cord -which’s incorporated into the plastic tube- into a thin layer of super glue. Go forward with your thread, and backwards to secure it well.

Step 4: Start hackle your material of choice, secure after completion and whip finish.

Update the head by curing it for durability.

Step 5: Calculate the required tail length -usually the rabbit strip length- and multiply by two.

Repeat steps 1 until 4. After completion you can tie in the middle of the tail, on top of the -rear- hook shank, by means of a number of figure eight windings.

What does this double mylar bonktail for ya:

This shape creates a thumping action, resulting in short bouncing pulses. These acoustic signals and pressure waves, are well to be notice at long distances. Combining them for example with a glass rattler, will create a variety of acoustics. (Betting on multiple horses!)

Thanks to Simon Graham and Jerome Servonnat