Trout dry flies don't float well

[Darian]

Aside from tying with synthetics (foam/cork), I second the use of Scotchguard to spray dries when I tie them.

[Fly Guy Dave]

I gotta try scotch guard. I’ve been using silicone spray from Walmart automotive section. I spray it into and fill an old mucilin bottle, the ones you flip upside down to coat the fly. Jay, have you compared scotch guard to other silicones ? Thanks

I would vote against using scotch guard, Thompson's waterseal or any other kind of petroleum-based product. I did this with a few dries several years back, and when the fly hits the water, there is the rainbow oily sheen that you see when gasoline or oil mixes with water. I can't imagine that is good for the health of any fishery. I would use the other products mentioned earlier.

[Zepher]

We may need a petroleum engineer like Dave Whitlock in on this one.

[Bob Loblaw]

My trout dry flies don't float well after I've used them for about a half hour even if I keep applying silicone cream, dry fly floatant or sprays. What's wrong?

All dry flies eventually start to sink no matter what you treat them with, especially if you've caught a few fish. What I have learned after starting to tie my own a few years ago is that if you pay attention to detail when tying dries, get all your wraps close and tight, cover up all butt ends, you can keep the water out longer. Not forever, just longer.