Fly Tying Thread Charts

Published Jun 13th 2014

For the true thread nerd: Charts comparing breaking strengths, Deniers and diameters for fly tying threads


OK, let's get really nerdy here! This is not for the faint of heart, I admit, but bear with me.

These charts plot different physical aspects and specifications of the threads, placing them in a so called scatter chart, which is a great way to find correlations between data. If there is any system in the plotted data, it typically aggregates in groups or along lines or curves.

As you can see there is no such grouping or order in any of the charts, which are chaotic to put it mildly. Of course it's not totally fair to mix all threads from all brands and expect a pattern, but even picking out a certain material (click the links above the charts) or focusing on a given brand (color coded), you will find no system.
A single manufacturer (Lagartun) has an almost linear correlation between thickness and Denier as well as breaking strength (seen when you look at polyester threads by themselves), but the rest are spread out like shots from a shotgun.

As you can see there is no such grouping or order in any of the charts
In the same manner mono threads from various manufacturers seem to have a nice correlation between diameter and strength, which is no surprise. It is after all a uniform, single nylon filament, basically made in the exact same manner from the same material.

But the thread landscape as a whole? Utterly confusing and with no common way of specifying the properties of a tying-thread.

Breaking strength vs. diameter comparison
This chart shows all tying threads placed according to thickness and breaking strength. Thinner and weaker threads are low/left, stronger and thicker threads are high/right.

GSP | Kevlar | Mono | Nylon | Polyester | Silk | All | *

Denier vs. diameter comparison
This chart shows the relation between Denier and thickness.

GSP | Kevlar | Mono | Nylon | Polyester | Silk | All | *

If there was a correlation between the compared data, all dots would be on a line or a curve.

* Some threads may be missing in the graph because I have no suitable data for them. The brand may still be listed in the legends, but no dots appear representing its threads in the chart. As soon as I get the proper data, the graphs will automatically show the newly added threads.

Work in progress
This article on tying threads and all the data that is part of it is work in progress and will be updated as soon as I get more or better information on the various threads.
If you have things to add, comments or corrections, feel free to contact me on You can also leave a comment to the article, and I will see it and respond if required.
I welcome contact from tying thread manufacturers with information, specifications, remarks or corrections - even criticism. The more the better!

Article | Table | Charts

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