Published Jun 13. 2014 - 9 years ago
Updated or edited Sep 11. 2021

Fly Tying Thread Charts

The nerdy look at tying threads plotting their thickness, Denier and breaking strength in scatter charts to show correlation. There is none!

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 brand (click the brand links next to the charts) or focusing on a given brand (same color dots), 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), and Veevus has a very nice and almost linear correlation between thickness and strength when you look at the polyester and GSP threads separated, but threads from the rest of the manufacturers are spread out like shots from a shotgun, indicating no consistency in thickness and strength or denier and physical thickness.

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.

Denier vs. diameter comparison

This chart shows the relation between Denier and thickness.

If there was a correlation between the compared data, dots would be on a line or a curve - or at least on several lines or curves, clustered based on the thread material.

* 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!

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