Thread and Whip finish

Tying thread:

There are many threads available today that have many different properties. The tyer will want to use the one that is most suited to the task at hand, in respect to thickness, strength, stretchability, waxed or un-waxed and weather it has a flat or round profile on the hook, And of course colour.

Size / thickness:

Thick threads are described in lower numbers  3/0  and thinner threads in higher numbers 16/0.  And strong threads such as Kevlar and Dyneema are as strong as carbon fibre. Silk threads and flosses are still available, but most modern threads and flosses are made from synthetic materials such as Rayon, Dacron, Nylon and Polyester. Stretchy flosses are normally made from Lycra. These modern threads may not please the purist but they do have a significant roll in contemporary fly tying.  Rayon and Acetate flosses are extremely shiny and I use them only for tags. If used for floss bodies they have a tendency to fray easily.


The following relationship applies to straight, uniform filaments:

DPF = total denier / quantity of uniform filaments

The denier system of measurement is used on two- and single-filament fibers. Some common calculations are as follows:

1 denier = 1 gram per 9 000 meters
= 0.05 grams per 450 meters (120 of above)
= 0.111 milligrams per meter

In practice, measuring 9,000 meters is both time-consuming and unrealistic; generally a sample of 900 meters is weighed and the result multiplied by 10 to obtain the denier weight.

  • A fiber is generally considered a microfiber if it is one denier or less.
  • A one-denier Polyester fiber has a diameter of about ten micrometers.

You will notice that for most of the patterns on this blog, I use only one type of tying thread, Dyneema.

This has several advantages when tying. Its a un-waxed super strong multi-filament polyethylene fibre that offers maximum strength combined with minimum weight. It is up to 15 times stronger than quality steel, on weight for weight basis. Dyneema floats on water and is extremely durable. Resistant to moisture and salt water, UV light and chemicals. Being a multi-filament thread it can be spun anti clockwise, and the fibers will open and flatten out, making it ideal for the largest of flies, splitting and spinning dubbing loops and tying with deer hair. Its also makes “O” build-up under tinsel bodies. If you spin Dyneema clock wise, the fibers twist together and become a super strong micro tying thread 16/0. suitable for even the smallest flies. The other advantage is that you need only one colour of thread, as Dyneema colours well with waterproof felt pens. The applications are therefore more or less unlimited. But it also has disadvantages. Being unwaxed it has a tendency to be extra slippery with some materials. So I either wax it when needed or change to a more traditional pre-waxed thread.

I will come back to Dyneema later and make a whole tutorial on its uses and related techniques.

Attaching Tying thread to the hook:

When you attach the tying thread to the hook shank, its not only for attaching other materials but lays a foundation for all the materials to be tied in, and stop them form slipping on the smooth bare hook shank.

If you have any questions about fly tying, techniques, hooks or materials please post them here and I will do my very best to answer them quickly.  


1. Holding the end of your tying thread in your left hand and your bobbin in the right place the thread behind the hook shank.


 2. Keeping tension on the thread with your left hand bring the bobbin around under the hook and cross the thread as shown.
3. Now make another turn of thread close into the first.
4. Still keeping tension on the thread in your left hand make six or seven more turns with the bobbin, keeping them tight into each other. If you are making a tinsel of loss body fly that requires a fine even foundation its important that the first wraps of thread on the hook are neat and even for good results. On the other hand if you are making a fly with a dubbed body its not so important. But once again if you learn to be neat with every pattern you tie, you will accomplish better looking flies all round!
5. Now you can trim off the butt end of the tying thread.
6. Tying thread attached, you can now carry on and cover the amount of hook shank needed with a thread foundation.
Whip Finish:
This is the knot used for finishing a fly, or tying off a section under tying to stop a material from moving while you progress to the next step. This is a technique that many new beginners find difficult to master, but once learned its never forgotten. Just take your time and practice the whip finish on a bare hook.
1. Holding the bobbin in your left hand, place the hook of the whip finish tool into the tying thread and over the bend as shown.
2. Now keeping tension on the bobbin with your left hand, turn your whip finish tool a half clock wise revelation so the tying thread forms a triangle and the thread from the bobbin is parallel with the hook shank.
3. Now keeping tension all the time in the bobbin turn the whip finish tool clockwise so it leads the tying thread around the hook shank two or three times.
4. Once you have made two or three turns around the hook shank pull the bobbin hand to the left while you tip the whip finish tool hand slightly upwards and let the thread slip off the bend, not the hook! of the tool.
5. Once the thread has slipped of the bend keep pulling with the bobbin hand but keeping tension in both hands and pull the hook of the tool down towards the hook.
6. Once the hook of the whip finish tool is tight to the hook just slip it out and tighten the tension of the bobbin to finish the knot. Trim off the tying thread to finish the fly. I tend to make at least two whip finish knots on dry flies and nymphs where the heads should be small and neat. But on larger and salt water patterns I make three or four.

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