Semperfli Pure Silk Traditional Fly Tying Thread
Semperfli Pure Silk Traditional Fly Tying Thread is a twisted pure silk, popular for traditional fly patterns such as spiders or Clyde style flies. If you are wanting to use Pure Silk flat, simply untwist it by spinning on your bobbin holder. This dual purpose means it can be used in different ways and has added strength compared to traditional silks. Pure Silk colors have been developed to be a close match to the historic colors of pure silks as seen in the Edmonds and Lee book Brook & River Trouting for which Semperfli is lucky enough to have an original copy.
| Specification | Detail |
|---|---|
| Denier | 250D |
| Length per spool | 50 meters |
| Color matching | Developed to match historic pure silk colors from early fly tying history |
FAQ
Can I use this thread in a flat form for fly tying?
Yes, you can untwist the thread by spinning it on a bobbin holder to use it in a flat form.
Are the colors accurate to historical pure silk patterns?
Yes, the colors are dyed to closely match the original silk colors as described in the Edmonds and Lee book <em>Brook & River Trouting</em>.
What is the strength advantage of this thread compared to traditional silks?
This thread has added strength due to its twisted structure, making it more durable during fly tying and use.




Kevin Mills –
The thread matches the historic colors perfectly and holds well in my fly patterns. I was able to untwist it easily for flat tying and it doesn’t fray during use. A reliable choice for traditional fly tying.
Gavin Russell –
I’ve used this thread for several Clyde-style flies and it performs consistently. The strength is noticeable compared to regular silk, and the color accuracy is spot-on for vintage patterns.
Abigail Sutherland –
Great for recreating old fly designs. The untwisting process is simple and the thread maintains its integrity during casting. Slightly more expensive, but worth it for authenticity.
Adam Martin –
The thread feels smooth and strong. I used it for both twisted and flat patterns and found it very versatile. Matches the colors in the classic books exactly.