Deciphering Fly Tying Thread Size

//Deciphering Fly Tying Thread Size

Deciphering Fly Tying Thread Size

By |2018-08-15T15:53:18+00:00August 15th, 2018|Skills & Kit|0 Comments

Thread Size for Fly Tying

Do the thread sizes listed in pattern recipes confuse you? Selecting the proper thread is far easier than you think.

Growing up I use to tie my flies with Mum’s sewing thread. I had no idea you could buy specialized thread in different colours and sizes for tying specific fly patterns. I didn’t think it really mattered and just grabbed what I could find around the house. A few years older jumping back onto the vise I discovered a entire section on threads for fly tying. It took longer than I would have liked after sifting through as much information as I could learning about all the different thread sizes and their applications. Ranging from 18/0 to 3/0 or 30 denier to 200 denier, about 10 different brands including UNI, UTC, Danville, Semperfli and more, flat, twisted, waxed. These threads each have their advantages and disadvantages. I wanted to post something that would help demystify the subject of thread selection.

Thread Sizes Explained

For decades, the diameter of fly tying thread was listed in “aught” sizes: 8/0, 6/0, and 3/0. Size A was also once a common fly tying thread; it was very thick, suitable for making very large streamers and saltwater patterns. Now the market is over saturated and trying to decide on sizes more difficult. The Essential Fly.com site has put up a fairly “direct to the point” article on choosing the right thread. Check it out!

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