I know it is hard to generalize, but I have been wondering how good spinning rod tapers differ from fly rods. More to the point, what action makes a blank a good candidate for a spin/fly rod? I have come across a few rods that work well for spin/fly purposes. However, most don't.

I prefer fast actions for both spinning and fly rods, so anything along that line works well for me in a spin-fly rod.

Obviously, a person that prefers a fast action spinning rod and a more moderate action fly rod isn't going to be satisfied with a single rod action for both purposes. But that's one of the trade offs you have to accept with such a combination rod.

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I also like a fast action on fly rods. 9 footers or more. Like to cast quickly. But also on shorter blanks I feel they should be more of a Med- fast not Mod- fast. Because of the shorter blank. Can not stand the Mod blanks, too noodle like for me. it is all in how you like the feel.

Bill - willierods.com

I would argue that it really isn't "action" that is important, it is frequency.

Action, i.e,, where the rod bends, is a constant which is defined at the time of construction. While it is indeed a function of taper, it has relatively little to do with the "feel" of a rod. A fly rod feels different from a spinning rod because it has a different frequency. A typical graphite fly rod (when fitted with the "proper" line, i.e., ERN=ELN) has a frequency of about 83 cpm. A typical spinning rod has a frequency of over 90 cpm. One can never raise the frequency of a rod without taking off some weight, but one can lower the frequency of any rod by adding weight.

I would also argue the principle function of a fly line (or weight of casting lure) is to adjust the frequency of one's fishing rod and line (i.e., one's fishing outfit) to match what I call the angler's PPF or Personal Preferred Frequency, which is unique to each angler.

Obviously, with a judicious choice of line (length of line outside the tip) or lure weight, one can adjust the frequency of any fishing outfit to match anyone's individual PPF. When that occurs, one has found his "sweet spot".

A blank, be it a spin blank or a fly blank, doesn't react to what it's casting, be it fly line or lure - only to how much it weighs. The choice of a fly rod's action is chiefly governed by personal preference, but it is possible to roughly predict what weight fly line a "spinning blank" will cast best.
For the vast majority of actual fly fishing situations I overline one or two weights, and the following suggestions reflect my preference. note: 437.5 grains = 1 oz..

A spin rod blank rated for a 1/4 oz. lure should "like" a 5 wt. or 6 wt. fly line

A spin rod blank rated for a 1/2 oz. lure should "like" a 9 wt. or 10 wt. fly line

A spin rod blank rated for a 3/4 oz. lure should "like" a 12 wt. fly line

These are only rough predictions (which you can verify if you do the math.) They can help narrow your search for "cross-purpose" blanks. I have built a few fly rods on blanks marketed as spinning rod blanks. Some were quite successful, some weren't. With the profusion of fly rod blanks available today I would hesitate to adapt a spinning rod blank into a fly rod.

Good points. The only time I do it is when I cannot find the exact length fly rod I want in a production fly rod blank model.

I've been building rods for over 30 years now and I don't think we've ever had this type of selection of powers. lengths, actions and models. I can see where it would be a little overwhelming to many beginners.

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I was wondering if spinning rods tend to have a softer tip relative to the rest of the rod. I have experimented with different weight fly lines on a few different spinning rods, and that was the impression I got. The tip was prone to flopping around excessively, bouncing after the cast, or opening up the loop.

Maybe it is my inexperience with spin fishing, but it seems most fly rods will do a passable job of spin casting.

Spinning rods run the gamut from fast to slow, glass to graphite. You can't really pigeon hole all spinning rods, or fly rods for that matter, under one action or power category.

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