The brush manufacturers make brushes with straight fiber monofilament fibers. I’m not certain of my statement since I’m not a chemist. All I know is that the fiber is all one size, and not tapered. You can buy some tapered bristles for painting. But the floor burns and dustpan type brushes the fibers are larger in diameter and straight.
In order to make the item more effective or efficient they treat the fiber tips by splitting them. I was told by a brush salesman the process for doing this is called “flagging”. They exposed the fiber tips to a high-speed rotary knife process that cuts the fibers ends and expands it into multiple smaller fibers, which assures the end user of a more effective tool for moving of finer surface particles. Let me show you what this process looks like to the newcomer like me. Here are fibers cut from the broom as it was taken from an unused broom.
At this point I stockpile a few fibers, 20 or so and I start inspecting them for possible use as primary or secondary legging. Use fine scissors for trimming. I look for the fiber to be useful for the next step in my legging process. Keep in mind, not every fiber will be usable. So if you have any doubt, pitch it. Don’t try to force the issue. About 50% will be a good average.
Lay these aside until you finish your first round of selection. I try to put the primary ones in four different piles, but this may be too premature for your first efforts. But for explanation purposes I want to explain what I mean by primary or secondary fibers. On larger flies I use two fibers per leg. On the smaller flies I use one fiber. Naturally I use the one fiber that has the greater detail as a single fiber. Here is a photo preview of what I’m referring to.
The natural bug has a claw and a single strand at the legging end. The double fiber has fiber tips starting slightly up the leg from clawed tip. This process of making two fibers to come together is not rewarding. But I used crazy glue and start by bonding the ends together, then the shafts. With care, you can do this without joining your fingers once the three shafts are bonded. They are cut to the side you need for the leg and it’s time and or glue and length. Once you position them using your crimping tool, and then you coat them. I use plain acrylic craft paint, and did paint with the use of a bodkin or a toothpick. This is not a fun process so use patience. I coat the upper leg portion or the femur with enough coats to give the leg more realistic topped appearance. You have to rely on your I for this phase. Painting also reinforces the leg set positions at the crimps.
My final process is a coat of flat spray lacquer to protect the paint from exposure to the water. It is a lengthy process, but I think you will be pleased enough to try it. Just look at these results that I am experimenting with.