Pattern Library
WD-40 fly pattern
Emerger · #7 of 129

WD-40

Imitates: Midge or BWO emerger

Quick Reference

Best Sizes
#18-22
Best Season
Year-round, especially winter
Best Conditions
Tailwaters, slow seams, midge hatches
Water Temp
Below 55°F
Recommended Tippet
6X fluorocarbon

How to Rig It

Dropper 12" off a Zebra Midge or Pheasant Tail.

How to Present It

Dead-drift just under the surface. Watch for subtle indicator twitches.

Why It Works

Sparse profile in the surface film perfectly imitates a midge struggling to emerge — the easiest meal on a winter river.

History

Mark Engler tied it on the San Juan River. The name is a nod to the lubricant — 'it works on everything.'

Pro Tip

Pair a #20 black WD-40 with a #20 olive WD-40 in winter and let the trout vote.

Frequently Asked Questions

What does WD-40 fly stand for?+

It's a tongue-in-cheek nickname after the lubricant — the original tier joked it works on everything.

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