Fly Tying Threads: My Unbiased Opinion on What Works and What Doesn’t
Fly tying thread is one of those deceptively simple tools that can make or break your tying experience. Over the years, I’ve tested most of the popular threads on the market, and I wanted to share my honest, no-fluff opinions about the ones I keep reaching for—and the ones I’ve retired to the back of the bench.
Threads I Love:
UTC Ultra Thread
Why I love it: Ultra Thread lays flat, splits easily, and comes in a great range of sizes and colors. The 70 denier is perfect for most trout patterns, while the 140 is ideal for streamers and larger flies. It’s strong for its thickness and easy to control. T
his is my thread of choice for tying midges and any pattern that requires a smooth body or thread base. UTC 70 in Red, Olive, Woodduck, and Black are staples on my tying desk.
UTC is also very easy to split with a bodkin. This makes it great for utilizing split thread techniques for dubbing loops, adding CDC collars, deer hair, rabbit, etc.
What I dislike: Not as strong as other brands, but proper thread tension alleviates this issue. Color from spool to spool may have slight variations.
Veevus Thread
Why I love it: Super strong and very consistent. It doesn’t fray easily, and I like how it handles under tension. The colors are very vibrant. The thread comes off the spool so smoothly. Veevus is my go to thread for larger flies. I always have 6/0, 8/0, and 10/0 available. I won't use any other non GSP thread for saltwater patterns.
What I dislike: It does not uncord as easily as UTC thread. The GSP is garbage. It is bound so tightly on the spool, which often results in the strands being stuck together. Out of the 10-12 spools I have used, all got stuck. Veevus GSP is terrible. There are better options like Semperfli Nano Silk.
Semperfli
Why I love it: This GSP thread is phenomenal. Despite its ultra-thin diameter, it's incredibly strong, far surpassing polyester or nylon threads of similar size. The 18/0 is amazing for tiny dry flies, while the 6/0 handles bulkier patterns with ease.
The Semperfli Classic Waxed Thread gives you a lot of bang for the buck. You get 240 yards in a spool, and it's available in a variety of colors.
What I dislike: The larger diameter classic waxed thread frays very easily. The smaller diameter waxed thread breaks more easily than Veevus, but it does lay flatter. The colored GSP threads will bleed. I just stick with black and white nowadays.
Threads I’m Not Crazy About:
UNI Thread
Why it doesn’t work for me: Some tiers love it, but I find it tends to build up bulk quickly and isn’t as flat as I like. The round profile can make clean heads and bodies harder to achieve. I also found it to break much more easily than Veevus, UTC, or Semperfli.
Sewing Machine Thread
Why it doesn’t work for me: You can get a lot of it for much less than fly tying specific threads. However, it's very bulky and frays easily. Most are cotton and break more easily than comparable nylon or polyester fly tying specific threads. Some older patterns do call for sewing machine threads (i.e., Yong's Special, Tenkara patterns, etc).
Final Thoughts
There isn't one brand that is the end all for my fly tying needs. However, knowing which spool to grab for specific types of flies is the key to an enjoyable time at the tying bench. There's nothing more frustrating than having your thread break, grabbing the bobbin threader, and repeating this several times.
I have specific go to sizes for each brand. As you experiment with different patterns, sizes, etc, your tying style might lead you to different favorites, but hopefully this gives you a solid starting point (or a reason to try something new).
