On one hand, we seem to agree on this forum that the spine of a rod is the outside curve when performing the technique to determine rod spine. Simple enough.

Not! . . . I get the new 2006 Mud Hole catalog and on page 4, lower right section on "Determining the spine of the rod", I am now told that "The inside of the curve is the spine. Mark the inside of the curve with masking tape or a marker".

Is there ANY logical reason why an industry cannot agree on one of the basics of rod building? Look at it from a beginners point of view and tell me why we have such conflicting information. This isn't rocket science, yet some things which should be consistent just aren't.

As a beginner, it makes no sense. Or, because I'm a beginner, is it a case of "I'm just not getting it"? If THAT'S the case, then please educate me.

Ralph, My guess is that MudHole got it Bass Ackwards. I'm interested to see what the real experts have to say. Just remember that Spine is not a THING but an effect.
Dave

TERMINOLOGY here and in other subjects in rod-building can be confusing and is not always universal. ... So much for the obvious, but it is worth stating explicitly, because sometimes on a Forum like this, the answer to a question lies in the fact that two Posters are using slightly different definitions for a term, ... or they are mis-understanding the terms that each of them is using. And chasing each other around the table.

Most rod blanks have a "SOFT-SPINE" and a "HARD-SPINE". These two planes of resistance to bending or "spines" are usually NOT occurring at exactly 180 degrees opposite each other. And the other thing which most rod blanks will have is a natural CURVE in the tip section. This curve may have little relationship to the axis of either "spine". A severe curve or kink may overpower the spine effect and really confound things. The difference in the resistance to bending among the soft-spine and the hard-spine may be dramatic or subtle. Your hands may be the most sensitive tool to measure this difference, and it may depend slightly on how and where you apply force when you flex the rod, and how deeply you flex it. Chances are rod every rod within a single model number will feel slightly different from others in the batch-run with respect to spine and curve.

Mud-Hole is recommending to orient the SOFT-spine toward the fish, when the rod is in the fighting position. This reduces the tendency for the rod blank to twist against your grip when the rod is heavily loaded by a strong fish.

Other rod-builders recommend orienting the HARD-spine toward the fish, when the rod is in the fighting position. This is supposed to increase the pressure you can put on a fish.

Many builders ignore the spine aspect and build on the CURVE, placing the "belly" of the curve "down", and placing the tip section and butt section curving "upward".

And many builders would say that honestly it makes relatively little difference in your casting distance, or casting accuracy, or fish-fighting ability which way the spine (or the curve) is oriented. ... So long as you like it, and the way it looks.

Factory made rods are apparently routinely built with no regard for spine or curve whatsoever, and the difference may mean more to us custom rod-builders because we can detect it, than because it inherently produces a real or significant difference in rod performance. ... Apparently, it does not.

In my own methodology, I prefer to put the softer spine toward the fish, to reduce torsion in the rod blank; and to assure for myself the easiest plane of orientation that I can reproducibly discover when I am checking the alignments of my components (reel seat and line guides).

Another recent Thread on this subject came up just last week.

Guides on spine side or opposite side?
Tom Danielson 11-27-05 18:56
[www.rodbuilding.org]
"Rolling the rod blank while the butt is on a table-top and the upper end of the rod is in my palm, the blank takes a set or a bow.
"Is the OUTSIDE of the curve the spine side, or is the INSIDE of the curve the spine side?
"For a casting rod, will the guides go on the inside line, or the outside line? … Is it the same for both spinning and casting?" -Tom Danielson.

'Hope that helps. Adopt a system that works for you and the kind of rods you build, and refine it based on your own experience, and you'll be fine. ...
Good Luck, -Cliff Hall+++, Gainesville, FL-USA+++



Edited 1 time(s). Last edit at 12/03/2005 04:44PM by Cliff Hall.

Right, and since the spine is not a physical thing, but rather an effect, all you are doing is referencing a particular position of the blank so you can remember it later. For this reason, you can mark the blank for "spine" anywhere you want and as long as you can remember what position and how your mark references is, you're not wrong - you've done what you need to do.

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After you have all that down pat, Look for the straightest axis of the blank and built it on that with the "belly" down.

Mike

I've never posted on this subject, the spine, before.

Looking at it from a perspective (and it isn't correct, and I know that) that one side of the blank has a thicker wall than the other side because of an off-center mandrel, etc, then the thickest part of the blank would be most resistant to bending and would be on the inside of the curve, when the rod is bent and allowed to move naturally where it wants to go (such as placing the butt on a marble and pushing down on the tip of the blank).

To me, that stiffer part, the inside of the curve, would be strongest and therefore the spine. But that's just me, logically looking at something and either over-simplifying it or...

I don't really care about the spine, whether it's an effect, a thing, or a figment of my imagination. I just look at the blank and align the crook pointing up, throw the guides on and call 'er good.

Putter
Williston, ND

I remember reading that the eyes should be placed 90 degrees from the spine on a casting rod. This allows the rod spine to work for you on a overhand cast since you are casting with the reel facing sideways in the casting position. If the rod is wrapped with a spiral wrap there is no rod twist once it has a load. Now does this make everything "clear as mud"? I need an opinion, please.

John Keys

It's my understanding that spine has no bearing on rod twist/torque, wall thickness or most things mentioned. A search on this site for rod spine or blank spine with ALL DATES checked should get you enough info/opinions to keep you confused for many moons.
Personally, I no longer even consider spine when building a rod (Caveat - I may be all wrong, just ask my wife!!) IMO, the difference, if any, would be immeasurable



Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

As a custom builder, I'd love to tell a customer that a rod that I build for him is better than that high dollar factory one (along with MANY other things) because of this whole spine deal. But it's just not the case. The spine just doesn't measurably affect anything IMO, HOO.

Putter
Williston, ND

A rod is made of resin impregnated substance of choice, cut into a triangle, then rolled into a long tapered cone, right? There will be 2 points where the rod wall is actually , physically thicker. The seam on the inside, where the material first contacts itself as it is rolled, and the outside seam, where the material ends. This seam runs the length of the rod. I doubt if the seams line up on the same side of the rod, inside and outside, and I doubt that they are offset in any sort of repeatable manner. So, in summation, I dont know alot, as I roll a rod around looking for spine I feel hard and soft spots, of differing degree of feel, but can usually find one area the rod really slips into easily, and mark that "spine" and put it on the bottom, but may change my opinion over time. Also, I could very well be totally wrong on how blanks are constructed. Maybe some are investment cast, with tiny carbon fibers and resin forced into a mold under incredible pressure. Dunno. I bet someone here does.

John,

What you propose is a very workable method for setting up a casting rod. I know Bill Colby does all his that way. I don't know that it makes all that much difference, but you are correct that most baitcasting reels are actually cast with the reel handle pointing "up." That's just the way the human wrist works.

The spine effect has more to do with than just where the pattern flags start and stop - there are at least 7 manufacturing anomolies that all contribute to the effect. Some are more apt to cause it than others, but all contribute.

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Tom,
May reasoning has been that with the strong side of the spine on the top of the cast, as you cast forward, the rod will aid in the forward motion thus reducing the stress on the caster. This would help reduce angler fatigue. For a plug caster it would make for an easier day of casting.
John Keys

Remember that the softest and stiffest axii of a blank are not 180 degrees opposite each other.

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