Sorry, guys. This whole spine thing baffles me. But let's assume that I have located the effective spine. I read last night that some (I think it was Forhan) does not line up the guides directly with the spine on a bass casting rod, but offsets the spine a little on rods that will be used for casting as opposed to flipping and pitching. His explanation was that bass fisherman tend to cock their wrist when casting, and you are really looking to align the spine with the casting arc--not the top or bottom of the rod. Any thoughts?

There is no right or wrong way to align the spine. It all depends on what you want the rod to do. At most, any particular spine orientation may result in subtle performance characteristics being enhanced or reduced.

The effective spine has almost nothing to do with casting accuracy and distance is determined by matching the correct amount of weight to the power of any particular rod axis (the idea that more distance is achieved by any particular spine oriention is dead wrong - that all depends on the casting load you're placing on the rod. The same spine orientation that gives the most distance with say, 1/4 ounce, might give the least distance with 3/8th ounce).

Many rod builders do prefer to put the spine in the same plane as the casting motion. On baitcasting reels, it's rare that anyone actually casts direction up and down - the human wrist does not work that way. Normally, the casting plane will be anywhere from 30 to 90 degrees from the 0 or 180 axis. The back of the casting hand is normally in line with the casting plane, to some degree.

The best thing you can do is mock up the rod and go out and cast it in the way and with the lures that you'll be using. Then you'll soon know which way you prefer to orient the spine on your rod.

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Tom,
When I first began building rods in 1960, a custom rodbuilder showed me two ways to "spine" a blank. The first was to place the tip on the flor and then gently push down on the butt imparting a bend in the blank. The rod blank would then roll into a stable position. The second method involved supporting the blank with your index finger under the blank about a third of the way down from the tip and then gently pressing down on the tip with the other hand to provide the flex. Again the blank would roll to a stable position. Any attempt to roll from this position and flex the blank, would result in a return to the "stable" position. I had assumed that the "spine" was the convex side and the most likely place for the guides for a spinning or fly rod were at the bottom or concave portion of the curve.

While my ability to do three dimensional force calculations are zero, my intuition leads me to believe that if guides were placed outside of this natural curvature plane, torsional forceswould result . I guess I would really like to hear from one and all about how out of plane flexing affects the rod blank. Thanks for listening.

Actually no. This is a bit of myth that has circulated for many years. In a fishing situation, you have guides on the rod, not a naked blank pressured by human hand. Any load placed on the line running through those guides will cause the guides to seek the lowest position. A rod with the guides on the bottom, such as fly and spinning, will never twist. Any rod with the guides on top of the rod, as in conventional casting, will always try to twist no matter where you orient the spine.

You can read more about this on the FAQs page.

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Lately I've been doing more and more with the curve or crook that exists in nearly rod blank. I think it has a lot more to do with casting accuracy than maybe the spine does. As far as rod stability I will concede that spine has nothing to do with that.

then why go to the effort of spining a blank if it doesn't accomplish anything?

I personally don't think that spine matters more than a minuscule.

I believe spine is one of those things that has come down from the past in an effort for the finished rod to look "correct". Can you imagine someone holding a new $600 custom fly rod with the tip cocked off to the right? Doesn't look like a good job of building. Nor could our forefather rod builders imagine the same thing when they began building rods themselves. So they figured out how to spine a road and then they taught us how to spine so the finished rod would not look funny, thereby reflecting adversely on the rod maker.

In essence, putting the spine either up or down is pure cosmetic.

The spine is almost never in line with any natural crook. In fact, rods that are spined, up or down, will crook off to one side of the other usually. Rods that are not spined and are built with the natural crook either up or down look straight when viewed by the fishermen.

For whatever it is worth, I have marked the spine. Then placed several blanks on my wrapper rollers with the spine at 0 or 180. put pressure on the tip. When I let go it would bounce in a straight up and down plain. Any other way the spine was it would bounce in a circular pattern. This tells me the spine has a lot to do with casting accuracy

Mike and Bill

You make two good points, both of which go to help my contention that spine is really not that important.

Mike - You say that a spined blank will normally or usually crook one way or the other. That being the case, then most rod manufacturers and rod builder either disregard spine or fudge on it a little to a lot in order to get the rod to lay straight in the owners hand. Therefore they are in fact saying that spine is really not that important other than in appearance.

Bill- Your test with a blank shows that a blank will react slightly differently when tweaked on the spine side and off the spine side. While that may be true for a blank, a rod with guides loaded with 30' of #5 fly line is not the same. I seriously doubt that any difference could be measured between the spine and an off spine setup when the completed rod is under a normal fishing load.

I have to admit that up until a year or so ago, I worried about spine in every rod I built. Then one day, I somehow mis-marked a rod with a definite, easily noted spine, completed the rod it and then found out that the spine was off to the extent that the spine was about 75 degrees to the right of top dead center. The rod layed nice in my hand with no side bend etc.

To my amazement, trying this rod on the river under actual fishing conditions, it was smooth and comfortable. If I did not know where the spine was in the rod, I would have never known that it was off the normal recommended way.

Since then I've tended to disregarded spine in favor of what I call lay-in-hand. My conclusions were re-enforced by Press Powell in Vol#7 of Rod Maker when he was quoted as saying the following about the 5,000 or so fly rods they make each year:

"Our system of mounting is kind of unique, everybody really cared, as each process went along. We have always mounted all of our rods by sight and I'll be darned, I have never seen any spining or anything else that is a better system. We always mounted on the opposite side of the natural curve, and even bamboo has a natural curve to it. What does the spine really matter? I hear about people who mount with it, on the opposite side of it, on the flat side of it, there are all these different philosophies. We have found our method works and we have never had a complaint, not one complaint."

Point taken Richard