Another FAQ in progress to support our beginner fly tying step by steps
In this one will discuss some basic thread handling techniques including
- thread twist (why it happens, how to correct it and how to use it to your advantage)
- thread torque
- different wraps used to attach material (Pinch, Angle, Distribution, Slide, and Slack Loop Wraps)
Thread Handling Techniques
In these examples I'm using a 5/0 hook and bright flat waxed nylon for illustration
Some basic terms referred to
- right hand if you wrap righty
- left hand if you're a right handed tyer
of the hook closest in relation to the tyer
of the hook opposite side of the hook in relation to the tyer
Basic wrap is going to be up from the near side and over the shank to the far side. Viewed head on from the eye of the hook, the bobbin goes clockwise around the shank for a right handed tyer.
What is thread twist and why does it happen?
Assuming you're wrapping by hand, every time you take a wrap around the shank, the bobbin makes one clockwise twist.
Problems caused by twist
This will gradually tighten the thread into a narrower and narrower cord and may eventually cause the thread to break. If thread is very tightly twisted it may also become more difficult to work with because it's harder to wrap a smooth thread layer, the tighter thread cuts into material, or it starts to "furl" by forming a loop and twisting up on itself.
If you leave your bobbin hanging from the shank (instead of in a bobbin cradle) after taking a bunch of wraps, you'll probably notice it start to spin counterclockwise (for right handed tyers). The bobbin is unwinding twist. So periodically you can let the bobbin do the work and let the thread unwind by itself to remove excessive twist.
Using thread twist to advantage
In some cases you'll want to deliberately flatten or twist thread to secure materials, build a smooth thread base or a firm platform. You'll often see instructions in fly pattern Step By Steps to twist or flatten thread. For a right handed tyer:
by spinning bobbin clockwise
By spinning bobbin counterclockwise
Example of flat and twisted threads:
Flattened thread (chartreuse)
Twisted thread (orange)
In this section will introduce several types of wraps,
Soft Loop Wrap - another method of attaching material. Depending on the orientation of the bobbin and the grips in your material hand it can be used to either lock material into a precise position or spin it around the hook shank (as in spinning deer hair)
Isolation Wrap - used to attach bundles of fibers to position them precisely, strengthen divided flank fiber or hair wings and parachute posts or provide distinct bands of color in a multicolored bucktail wing
Distribution Wrap - used to distribute materials by rolling them around the shank
Slide Mount Wrap- used to secure materials to the shank and then adjust to proper length by pulling them into position
Figure 8 Wrap used to divided wings on dry flies, attach dumbbell or beadchain eyes and constructing bodies of dubbing and other material
Thread Torque (examples of problems caused by thread torque and how we can control it and use it to our advantage when securing materials)
Angle Cut to taper the butt end of materials
very useful, especially to attach soft materials.
Place material on top of shank and index finger of material hand firmly against far side of shank. (This will backstop the material and prevent it from twisting to the far side as you take a turn of thread)
Place the thumb of your material hand tightly against the near side of the shank and pinching both the material and hook shank between your thumb on the near side and index finger on the far side of the shank
As you cross over the top of the hook, bring the bobbin rearward to trap it between your thim and index finger in the pinch
As you cross over the far side of the shank, bring the tip of the bobbin rearward on the under side of the to again trap the wrap in the pinch. This will allow you to precisely position the material and begin to secure it in place. Repeat these steps with another wrap or two.
After 1 or 2 more wraps the material should be secure enough that you can remove your hands to take a peek
a few more tight turns of thread will secure it
In this example we want to build a smooth under body, so we're leaving a long portion that we will wrap over. Once we bind it down with additional thread wraps it will form a smooth under body of even thickness. If we cut the butt end shorter, say to cover just the rear half of the shank, we'd have a bump when turned over the portion of the shank with just a layer of thread.
But when trying to lock the material down and build a smooth under body, thread torque takes it around the shank
We can undo the wraps and lift the butt end of the body material, advance thread in open turns towards front of hook to tie-down point....
... and tie down material with pinch wrap.
Open turns to rear to bind material to top of shank and form smooth under body.
Cutting materials to get a more gradual, tapered transition to the shank. Cutting material with the scissor blades in a vertical position will result in a "cliff" of material where the butts are trimmed, requiring many wraps of thread to build up a gradual taper. When butts are trimmed into a "cliff" it also often results in poorly fastened material since only the outer layer of fibers may be in contact wit thread. Instead, angle in with the tips of your scissors in a more horizontal angle and lift up the butts and cut, leaving a smooth "ramp" that you can easily cover with tight thread wraps
Return thread in open turns to what will become the tie off point for the body material
Danger Danger-- after wrapping in touching turns up the shank and binding the material down on the bottom of the hook, we want to trim the excess. But see how easy it's going to be to cut our thread too?
Before we zoom in with our scissors to trim, the excess material is hanging dangerously close to the thread. To avoid cutting the thread too, if you have a rotating vise, spin it so the hook point is up to get safe access with your scissors to make the cut. If your vise doesn't rotate, lift the thread bobbin straight up above the shank with your material hand to give you plenty of room to safely cut the excess body material
Once the excess material has been cut, you bind the material securely and build a thread foundation for the next layer with additional wraps
Continued with more stuff below....