I like to build spinning rods so the stiffest arc is on the back of the rod.
I used to build conventional rods just the opposite, and then I went to spiral wrapping my rods, so back to the back being the stiffest.

It probably makes little difference in reality, but I was taught this many years ago, and old habits die hard!

I made a spine finder and I was so proud of it. Now it will collect dust. My fault I should have asked everyone before I made one. I was having a very bad night and did this spine finder to get me through the treatment.

If you want to know the spine, fine. It doesn't take a tool you need to purchase. Just flex the blank on a carpet and you'll find the spine. Then build as you want.

I have made and sold many spine finders, I don't use the spine finder to determine where to place the guides but to demonstrate what the spine does and how to find it.

I don't mind reading posts that discuss the spine, when the thread gets tedious I stop reading and go off to other things. It may be boring and irrelevant but the newbies may find the spine posts interesting.

The spine discussions may be excruciating for the old timers and the subject matter is dull andnever changes but the audience does and that is why it perpetuates.

Have fun.

The problem with spine finders is that they do not duplicate what happens in real world fishing rod use. Use a spine finder on a naked blank and it rolls one way. Add guides, run a line through them and pull on that like a fish would and try it again on the spine finder --- the blank will flip the opposite way until the guides are on the bottom.

Lynn ......... you da man !!! LOL


Edit for addition ........ back in the day, very prominent and highly regarded people thought the Earth was flat. That it was like a table top, and you could just walk off the edge. That train of thought was deeply entrenched in society until it was actually proven that the Earth is round. Yet to this day,, despite proof that the Earth is round, we have The Flat Earth Society.



Edited 1 time(s). Last edit at 05/14/2023 07:42AM by David Baylor.

Sam, a spine finder may not be necessary, but you spent some quality time working on an interesting project that helped you get through a tough time in your treatment. I would call it a win.

You now have a device that you can use to demonstrate why spinning the blank is unnecessary, while also being able to demonstrate why a spiral wrap for a casting rod is stable under load.

I wish you all the best as you go through treatment.

I don’t think there are too many applications where you can get away with saying, I’m providing you a tool built that orients the material so that it’s weakest axis is aligned with the axis that is asked to carry the highest load and that this orientation may offer benefits that cannot be proven to be statistically relevant through experiment. Would you buy a box wrench where the thinnest part of the shaft is rotated 90 degrees so you apply force across the thinnest part of the cross-section?

The spine concept is ‘science’ developed from Aristotle’s school of thought where much of the effort went into finding cases that provided confirmation of a hypothesis instead of time spent understanding why many cases did not fit the hypothesis. This approach leads to confirmation bias and the reason why Aristotle’s teachings on natural philosophy have been debunked and replaced by Newtonian physics, and relativity and quantum physics where Newtonian physics fails. If physics can self-correct, rod builders should be able to do the same.

That said those flawed concepts take a very long time to disappear. Even Aristotle’s concept of antiperistasis (the notion that as matter moves through a fluid that the fluid will rush behind to fill the void pushing from behind and propelling the matter forward) that has been debunked for centuries still pops up in discussions regarding how fish can hold in current. Those eddy currents do not help the fish hold in place just as a semi is not propelled down the highway by its wake.

The spine of a blank falls into a similar trap. Yes there is a plane of least resistance, and it can be found by loading the blank at 2 points. The problem is that once the blank is loaded at more than two points that are offset from the surface of the blank, the conditions are significantly different and the line will seek the shortest path length as it loads the blank in multiple locations. Simply using Sam’s spine finder and blanks with guides located along various axes will demonstrate how a blank flexes under load generated at N>2 points along its length without bias.

That doesn’t mean that knowing where the softest axis of a blank is located is entirely useless. If an astute angler wants to really push the lower limits of a blank for casting light lures, then knowing the orientation of that weakest plane can be used to their advantage. The problem is that if the casting stroke deviates very far at all from that plane, it becomes a moot point, but I’m sure there are a handful of elite casters out there that could take advantage.

It’s the edge cases like this where custom rod building can become truly custom.

Tom, if your original rod building guide book is out of print, it would truly benefit the community to have it shared on the site. Even though some of the hardware shown in images is a bit dated, the fundamentals of how to make decisions in rod building are still 100% relevant.

Joe,

Yes, it is out of print now. The publisher printed 40,000 copies and once those were gone that was it. I do not expect him to publish a 2nd edition at this point.

Because I never owned the copyrights to that book. It's not something I could legally share here or elsewhere. Sorry.

.........

If spine was of any importance there would at least be a consensus from those that wrote about it. Gene Bullard’s book never mentions it. C. Boyd Pheiffer wrote two books and neither mentions it. The Herter’s book never mentions it. The GudeBrode book never mentions it. Tom’s book mentions it but explains what it will and will not do for you.

Dale Clemen’s wrote two books and in the first one he says the spine is the where the rod “kicks” away from you and in the second he said it was where the blank settled into a place where it did not want to move. He couldn’t even agree with himself from his first to his second book. Take any other book author that wrote about spine and half will use Dale’s first description and the other half will use his second description. Clemens started all this from an observation he made. He never had any evidence or data for his claims and all of those claims were based on what happens when you flex a blank by hand not what happens when the rod is loaded by a fish pulling on a line running through the guides.



Edited 1 time(s). Last edit at 05/14/2023 12:55PM by Mike Ballard.

"I never have any bias going in on the tests I do for the manufacturers. It is the results from those tests that create my position - not the other way around. For instance, my research on blank breakage now hangs in the warranty departments of rod manufacturers around the globe. It was impossible to have any bias going in, as none of this stuff was known. Sometimes you suspect things but it is the testing that either confirms your suspicion or requires you to change it.

Any good custom rod builder can glue a tiptop on a blank and feel the difference between that and the naked blank. At least until you start talking about very heavy power blanks. And it's worth remembering that the little things by themselves don't mean much, but added together many little things do make a difference. The original question was had I done any tests to prove my statement that building on the stiffest axis results in higher rod speed than if you built on the softest axis. Yes, the tests were done and results proved this to be so. Saying that the difference is not enough to matter does not overcome the fact that the difference is indeed there. Whether or not that difference is worth worrying over is up to the individual rod builder.

By nature of being a relative system of measurement the CCS is not at all imprecise, unless the person taking the measurements is imprecise"


I do not attempt to diminish your effort, and want to acknowledge and commend all you do for rod building, which to me is not a livelihood but an occasional hobby. So I have no real stake in this debate, but enjoy a good discussion. BUT we all have inherent bias, be it conscious or unconscious, as it is the nature of the human mind. In reality, there is no such thing as having an open mind when going into a product evaluation. Controls and exact measurement are put in place to obtain data to eliminate those inherent biases. If we had no inherent biases, then we would only need one Supreme Court Justice and one person on every jury. We all perceive and "feel" things differently and uniquely.

I spent 30 years in a consumer product industry and saw countless taste tests conducted with consumers. When it comes to perception, taste buds are amazingly sensitive. I continually witnessed people taste an array of unmarked products, often rating lowly the product they claimed (based on their experience and personal taste) was their favorite, while rating a product they would never buy (due to its taste) as being their top choice in a blind test. Typically individuals could not with statistical accuracy pick their personal favorite brand from among a half dozen different samples within the category.

If your life depends on a drug, you would be most glad of the rigorous, highly-controlled, double-blind, randomized, repeated and peer reviewed testing that is conducted by drug makers and the FDA. Millions of people per year will take an antibiotic for a cold and swear it made them better. This is a scientific and biological impossibility. But that is what they say they "feel," and they believe it 100%.

Measuring fishing rod blanks is far from a critical or a life or death issue, but a more true scientific methodology would be required to obtain exact measurements and data in order to truly obtain a blank's characteristics. Flipping a blank, rolling a blank, sighting down a blank, hanging pennies from the tip of a blank, are all readily available, easy, well-intended and inexpensive and rapid approximations of measuring the blank's characteristics. But I would content none are exact, though perhaps plenty good enough for our need. And none of this relating to axis may have enough of an effect on true rod performance to enable a person to perceive or "feel" a difference in a well made blank.

I indicated that I was confirming that I think your straightest axis claim is probably the more accurate of these readily available but non-scientific ways of aligning a blank. My point is a more true and exact method would not be that expensive or exhaustive for blank manufacturers, or a rod enthusiast or entrepreneur, to create, since it already exists in the evaluation of golf shafts and other tube analysis.

And, in my opinion, none of this matters if the rod maker/designer has not designed a quality taper to begin with. Sadly, you can have the best aligned rod in the world, but if the design of its taper @#$%&, then you still have a lousy rod.

Tight lines to all. Runoff in the Rockies is starting to crank up, so it's flatwater or nothing for a while.

The only way to have a bias is to enter into such research or tests with a hypothesis, which we didn't have. Nor were we trying to prove anything in particular. I was sent several hundred first quality, same model blanks and asked to break them and "tell us what you find out." So that's what we did and I reported the various findings via a series of articles.

..........

David Baylor Wrote:
-------------------------------------------------------
> Lynn ......... you da man !!! LOL
>
>
> Edit for addition ........ back in the day, very
> prominent and highly regarded people thought the
> Earth was flat. That it was like a table top, and
> you could just walk off the edge. That train of
> thought was deeply entrenched in society until it
> was actually proven that the Earth is round. Yet
> to this day,, despite proof that the Earth is
> round, we have The Flat Earth Society.


yes and the Son revolved around the earth.

Tom , while I cannot speak for David, I think that he is referring not to your objective testing but to your ability to detect the difference in feel/response (subjective) between a blank with a tiptop and the same blank without. Or similar evaluations. I believe his point is that any subjective evaluation has the risk of biases that may even be unknown to the tester but might affect the conclusions.

We used to do that with blindfolds way back in the 80's which made things less subjective although not absolute proof. But hardly anybody ever got it wrong. Just a tiptop vs no tiptop. In later years the numbers proved it.

I don't know about other people and won't hazard a guess, but I guess I may be an odd bird in these type matters. If I go into something even suspecting a particular outcome, I try to prove myself wrong.

............

I am not referring to blanks with tip top on them and without, as that does add weight and, even while minute in amount, it might be perceptible.

My point is that in a quality made blank, in a properly controlled test, I doubt whether you would "feel" a difference between a rod that is built on the straightest axis and one that is not. In controlled, randomized, blind tests with much more accurate measuring devices than used in fishing rod blanks, golfers continually choose wrong in regard to axis alignment, and extremely precise measuring devices show no statistical difference between a randomly oriented shaft and one that is aligned by a patented system called PURE, or by club builders using a very similar but more mechanical system known as FLO -- flat line oscillation.

The physics says there should be a difference but, if there is, it is so small that one cannot detect it. But people swear they feel a difference.

What people say they "feel" or "taste" or "hear" in testing is often not the truth, nor what the data say, or their choices just are not proven to be statistically significant. And this happens again and again in properly run tests. Here are a few real-life tests using expensive, high-quality graphite golf shafts which use high-precision measuring devices:

[www.youtube.com]

[www.youtube.com]

That's why I did the tests and ran the numbers. There is a difference.

As far as feeling the difference in a naked rod blank and the same blank with a tiptop glued on, try it yourself. Get your fishing buddies to try it, all blindfolded, or course.

..........

@Tom - I believe David, correct me if I'm wrong, is stating that anybody on this board or IRL wouldn't be able to tell the difference between a rod built on the spine or straightest axis or on its spleen or if the spine had Scoliosis. I believe him, I imagine the real world difference to be imperceptible to regular humans. I think part of the reason is this:

[www.youtube.com]

Start the video at 7:22 and watch how this rod behaves when casted in this manner - practically got suplexed haha no matter the orientation of the build it makes absolutely no difference in this situation where the rod is treated like a contortionist during the cast. We don't always cast the same way so it really makes minimal difference how the build is oriented.

This guy has laser beam homing on his casts, from all angles and types of casts and I don't think there was a whole lotta custom straightest spine building done to his manufactured rod.

Building rods in MA, Building the community around the world

I know that there is a difference in ERN for the CCS measurement if you measure on the spine versus any other axis, with the measurement on the spine always being slightly less. I was always surprised that the inventor did not specify that the blank be turned a certain way so that things would be more consistent. Maybe because it was designed to be used by manufacturers he figured they would do that on their own. With rod builders using it I think a particular alignment would help make the results more consistent.

Mike Ballard Wrote:
-------------------------------------------------------
> I know that there is a difference in ERN for the
> CCS measurement if you measure on the spine versus
> any other axis, with the measurement on the spine
> always being slightly less. I was always surprised
> that the inventor did not specify that the blank
> be turned a certain way so that things would be
> more consistent. Maybe because it was designed to
> be used by manufacturers he figured they would do
> that on their own. With rod builders using it I
> think a particular alignment would help make the
> results more consistent.

Good point. It seems (to me anyway) that when your loading weight on the blank to measure, the blank has a tendency to orient naturally.

Tom....after reading your article on the straightest axis I am going to try it on my next build when I find tip & butt up on my rod stands and building a spinning rod the guides would be placed 180 degrees of that finding correct?