Bob - you have struck a different kind of chord with me. I have always liked to evaluate fly rods, and have ffished nearly a thousand of them and casted several thousands. I love to discuss the engineering and wave dynamics of these with rod makers, a few of which have scientific backgrounds but mostly don't.

Our own BillT is a cane maker who specializes in quads, because the fact that so few have been made in years past means that the design front is wide open. He terms the format 'liberating', since most of the successful hex tapers have already been established by Leonard, Payne, Garrison, Winston, Thomas and Paul Young (no relation). With the exception of the Sir D, the tapers are nearing the century mark. The great designs by Kusse, Aroner, John Channer, Marty Karstetter, Bob Sigman and others could be construed as tweaks on the core designs.

The same applies to pents, tho' probably not to 3 sideds. The one and only 3 sider I've casted was done by Bill Fink, and he will never do another. The assymmetry of the cross section means that the forward and back casts are way different, which is disconcerting to say the least.

Yes - the 4 and 5 sideds do lend them to directionality - but this is what all the plastic makers strive for. Gatti is most uniformly successful with this, but certainly the products by Sage and others that get to the fly shop are quite good. The non-pejorative term is tracking.

Hexagraph already does with plastic what you are suggesting - but with hexes (no surprise?). The original English designs were maybe suitable for wet casts on some English tidal rivers, but were not popular with dry fly anglers. When the great Walton Powell hooked up with them, he really advanced their castability and ffishability (not at all the same thing). I prefer using these to hollow plastic tubes when in boats (especially with metal gunwales) and when bushwhacking.

tl
les