I stripped an old Fenwick 6'-6" rod. I checked the spline. I was surprised to find the spline was off by almost 90° . Back in 1998 this was an expensive rod. I thought Fenwick was a good rod. I can't believe Fenwick skipped setting the spline.

I repaired a Fenwick rod the other week, tackle store just gave me the top half of the two piece rod, looked custom with the old fuji guides

But it wasn't..the spine was on the side, understandable(expected) for mass produced rods.



Edited 2 time(s). Last edit at 05/09/2023 11:14PM by Josh Bryan.

The "spine" is of no concern. It was something that an insurance salesman coined back in the 1970's. There is no data to show that it makes any difference in rod performance. No particular orientation of rod "spine" affects casting accuracy or rod twist.

Conversely, there is hard data to the contrary - [www.rodbuilding.org]


...........

Tom Kirkman Wrote:
-------------------------------------------------------
> The "spine" is of no concern. It was something
> that an insurance salesman coined back in the
> 1970's. There is no data to show that it makes any
> difference in rod performance. No particular
> orientation of rod "spine" affects casting
> accuracy or rod twist.
>
> Conversely, there is hard data to the contrary -
> [www.rodbuilding.org].
> pdf
>
>
> ...........

Well, I'll continue to set the spine on top, might as well when the blank is bare.

Makes for better fish fighting comfort, most of the time when the fish is underneath

And sets it apart from mass produced rods.

I trust Gary Loomis, I'm pretty sure he's not an insurance salesman and he still to this day advocates for building on the spine:

[www.youtube.com]

Building rods in MA, Building the community around the world

Guide orientation determines whether not a rod will twist under load. ALL rods with the guides on top will attempt to twist when a fish is on the line. Spine orientation will not overcome the lever arm effect of those guides. Rods with the guides on the bottom of the rod will not torque nor twist when the rod is under load. The only way to make a rod stable is to place the guides along the bottom of the rod.


.........

Gary doesn't mention rodtorquetwistload once in that video.

Building rods in MA, Building the community around the world

Sam,
Thanks for introducing a new word to my vocabulary --- Spline

[en.wikipedia.org])

I did not know what that word meant in the field of Mathmetics.

Thanks again.

He also isn't referring to the "spine" that many rod builders are. The stiffest axis will be along the blank's straightest axis, which is the natural curve that places the belly down and tip and butt high. That is not the spine nor is it 180 degrees opposite the spine. The spine is simply the weakest or softest axis. And it is not opposite the stiffest axis.

...........

oh good.... this again....

Facts are rarely accepted but myths die hard.

Tom, if you watch the video you will see that Gary rolls the blank to find the spine in the traditional sense, never once does he even imply anything regarding a straight axis. I'm not sure if this is some fallacy of ambiguity here where you are somehow referencing some specific different spine than most people mean when they talk about this - when you say "MANY rod builders..." I'm not sure who you mean, because all over this forum and everywhere else on the internet people seem to mean spine/spline exactly how Gary describes it.

roll the blank like Gary does and where the rod wants to rest naturally is how you find the spine and then build accordingly, just as Gary describes. He is referring specifically to the spine that most people are referring to when this topic comes up and the only mention of a natural bend he says will be on the spine already anyway and then goes on to absolutely disregard any other straightness/curve in a blank and just explains how to build according the the spine.

[www.youtube.com] Even Batson recognizes that people say spine/spline, but this is what we all mean when we say it.

Mud Hole's definition is the same [www.youtube.com]

Voodoo Rods agrees on the definition [www.youtube.com]

Get Bit Outdoors has the same definition [www.youtube.com]

Edit to add:

Gary's explanation for why the spine and on which side he builds is actually much more reasonable and actually contrary to others.

And sometimes truths are called myths when people agree to believe something else.

Building rods in MA, Building the community around the world



Edited 1 time(s). Last edit at 05/10/2023 10:33AM by El Bolinger.

Is our best argument really that Gary Loomis says to do it?

Al Jones Wrote:
-------------------------------------------------------
> Is our best argument really that Gary Loomis says
> to do it?

Appears to be, yes, but like Tom said Gary is not really talking about the same spine that most rod builders. All that stuff came from Dale Clemens way way back. Or you can realize that if building on the spine was somehow superior then why doesn't it make a superior rod? All it does is make a weaker rod and it does not stop the rod from twisting or make it more accurate. Those are just beliefs. A truth is something you can prove. Building on the straightest axis makes a stronger rod when lifting. And putting the guides on the bottom of the rod is the only way to stop rod twist. These things have been proven.

El Bolinger Wrote:
-------------------------------------------------------
> Tom, if you watch the video you will see that Gary
> rolls the blank to find the spine in the
> traditional sense, never once does he even imply
> anything regarding a straight axis. I'm not sure
> if this is some fallacy of ambiguity here where
> you are somehow referencing some specific
> different spine than most people mean when they
> talk about this - when you say "MANY rod
> builders..." I'm not sure who you mean, because
> all over this forum and everywhere else on the
> internet people seem to mean spine/spline exactly
> how Gary describes it.
>
> roll the blank like Gary does and where the rod
> wants to rest naturally is how you find the spine
> and then build accordingly, just as Gary
> describes. He is referring specifically to the
> spine that most people are referring to when this
> topic comes up and the only mention of a natural
> bend he says will be on the spine already anyway
> and then goes on to absolutely disregard any other
> straightness/curve in a blank and just explains
> how to build according the the spine.
>
> [www.youtube.com] Even
> Batson recognizes that people say spine/spline,
> but this is what we all mean when we say it.
>
> Mud Hole's definition is the same
> [www.youtube.com]
>
> Voodoo Rods agrees on the definition
> [www.youtube.com]
>
> Get Bit Outdoors has the same definition
> [www.youtube.com]
>
> Edit to add:
>
> Gary's explanation for why the spine and on which
> side he builds is actually much more reasonable
> and actually contrary to others.
>
> And sometimes truths are called myths when people
> agree to believe something else.

Are we "Beating a Dead Horse"?
He actually does mention straightness of the blank at 1.35 in the video. The guides are going to make the blank bend where it is supposed to bend. The great thing about a custom rod is you can build on the spine, the straightest axis, spine up or down, tip up or down or even with total disregard for for any of it, for whatever reason you have. I have cast 4 pc fly rods that were totally built on the spine, disregarding the straightest axis. They looked weird but actually cast great. With the same blank built on the straightest axis, it also cast great with little or no perceivable difference.
Does it matter? The answer is "Yes", if it matters to you.
It's your baby.

Gary interprets the "spine" as being the stiffest axis, which is also the straightest axis. That lies just about on the blank's natural overall curve.

Most custom rod builders and rod building books define the spine as the plane of least resistance. It is neither the straightest axis nor is it opposite that. Most often the spine (weakest axis) will be anywhere from 90 to 170 degrees from the stiffest/straightest axis.

...........

Gary interprets the spine in the video Tom, people can watch and see that he doesn't agree with you.

@Al, no argument here man - I gave up building custom rods decades ago. Shimano has a rod that is 140% more sensitive so that's all I use now - and they build on the curve of the straightest spine, but put the guides on an axis.

@Mike, you're right - ignore what Gary said because Tom said.

@Lance, wish I could like your comment bro, most reasonable thing said in this thread haha. Aside from useless dead lift data there is no data about the impact of spine or axis from either camp - Gary makes claims and others make claims and nobody has data. I don't think it would really make a humanly discernible difference either way - I don;t usually roll my fishing rods on the ground while I'm fishing haha. I've advised in other threads about this the same way - just build it how you want because obviously it can't make that much of a difference, people use store bought rods more than anything and spend $400-$600 for a rod that isn't on its spine and they love it. Custom build your custom rod however you wanna - just make sure you do it the right way or the other side might show up to correct ya ;)

Building rods in MA, Building the community around the world

Regardless of if it matters, one thing that stood out the most to me is Mr Loomis actually describes placing the guides opposite of what most other companies or videos suggested.

When I first started building, I learned that when determining the spline, spinning guides go on the inside of the curve, casting would be placed on the outside. In the video, Loomis said that spinning guides should be placed on the outside of the curve.. not sure what is right but Loomis is obviously one of the most knowledgeable builders ever to live.

The data for deadlift capacity is not useless - it proves something in terms of the strongest orientation for rod blank use.

There is no data to prove or even suggest that building on the spine increases accuracy or eliminates rod twist. Both fly in the face of physics.

..........

Evan Cobb Wrote:
-------------------------------------------------------
> Regardless of if it matters, one thing that stood
> out the most to me is Mr Loomis actually describes
> placing the guides opposite of what most other
> companies or videos suggested.
>
> When I first started building, I learned that when
> determining the spline, spinning guides go on the
> inside of the curve, casting would be placed on
> the outside. In the video, Loomis said that
> spinning guides should be placed on the outside of
> the curve.. not sure what is right but Loomis is
> obviously one of the most knowledgeable builders
> ever to live.


Gary is putting his guides so the rod is oriented to the stiffest axis which is not the spine nor the opposite of the spine

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