This week’s Throw Back Thursday Fly is the WD-40.

WD-40 |

The WD-40 was developed by Mark Engler for the Frying Pan River in Colorado back in 1982.

The WD is for Wood Duck, which is used in the tail and wingcase, although I’ve seen the fly tied with Mallard Flank as well. The fly can be used to imitate a small Baetis / Blue Wing Olive or midge.

The original fly pattern was tied with a gray body/thorax, but it can be tied in a variety of colors including olive, chocolate, black, tan, and red.

I plan to fish the WD-40 as a dropper off of a dry fly or nymph. This time of year, the flies are getting smaller and this fly looks like a good imitation. And I need to learn and fish more midge patterns.

If you tie the fly, be sure to dub a thick thorax to imitate the swollen wing pads of the Baetis mayfly or midge.

Enjoy…go fish!

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  1. Nice WD40 fly. But what color is wood duck. I color blind an wood like to know what color to use for the tail and wing case.

    1. Martin

      Thanks for your comment. Many tyers use mallard-dyed wood duck as a substitute. Real wood duck has a tinge of yellow with bronze being the main color. Many use this feather because of the barring.


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