If you tie four size 18 Rusty Spinners, all with TMC 100 hooks, with identical microfibbet tails, identical poly yarn wings, identical Superfine dubbing thoraxes, same thread, but with four different abdomens made of:
2. Goose biot
4. Superfine dubbing
Which would float longer without any floatant being applied, again all things being equal? Or would the fact that they are such small flies on light hooks the abdomen material doesn't make any difference, as long as it is a material that doesn't immediately soak up water?
I vote for biots, but since I tie all my spinners (except tricos) with biot bodies I'm a bit prejudiced. Floatation isn't much of a problem, but then I tie mostly Barr Hi-viz spinners which are hackled, so that probably wouldn't answer your question.
I like to use superfine dubbing. I think it floats fine even without floatant. Like most flies, does require a few smart false casts to dry off every few drifts........
Tie up one of each, put them in a bowl, check them,every so often.
This is not an acturate test on a stream, but would work for a lake test. Stream test would require a fountain or fish tank with constant rippling surface
Not fair, Not fair!
Superfine Dry Fly Dubbing (to give it its full name) is treated before you buy it. You are comparing 3 untreated flies with one that has floatant on it already.
Could you also explain the tying process by which you get "all things equal"? I've been trying to achieve this for years.
Recently I've been tying tiny olive spinners for a customer. CdL tail and poly yarn wings with just a thread body. To get the colour I apply brown cobblers wax to Lt Cahill Uni thread 8/0. Is this a floatant? A side effect of it is stopping the water soaking into the thread.
To borrow a phrase from Hans, "Running and ducking." ;)
Simply for floatability on it's own merit?....I would say the biot. Superfine dubbing, though treated, is a dubbed material with gaps of air which may not "absorb" water, but will "collect & hold" water and eventually sink.
When tied on a hook however, dubbing have fibers that hold in the surface film....biots have little, and I feel would sink faster.
Look forward to a test. :)
With the parameters you've set, I think they'd all float long enough to be out of sight by the time they started to sink. However, and just a guess, maybe the quill might last longer because it has a natural resistance to water, then the biot, dubbed body and the first to 'sink' would be the thread body. By the time the fly sank though, the hatch might be over and the trout may be looking for wet flies, lol.