People who build on the straight-stiffest axis at least have some hard data as a reason for building that way. People who build on the spine have nothing other than opinions from a variety of sources none of which have never proved it or supplied data to show that building on the spine makes a better rod, stops rod twist, or makes for more accurate casting. They are the ones that need to step up and provide data to back up THEIR statements. That is what started this conversation--- somebody said they thought Fenwick built good rods but when they stripped one down it was not built on the spine. But like always happens they did not and cannot provide any proof or data as why a rod built on the spine is better.

Tom Kirkman Wrote:
-------------------------------------------------------
> 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
>
> ..............

Yes, that is what I meant.. Mr Loomis suggested placing spinning guides along the stiffest axis, and casting on the opposite side to balance the effort/energy and improve rate of return. Regardless, still the opposite of what most companies suggest and what I’ve been doing, which has been placing spinning guides on the inside of the curve (or softest axis)



Edited 1 time(s). Last edit at 05/10/2023 02:57PM by Evan Cobb.

A marketing perspective on this issue: Custom builders can orient guides to the spine (or opposite the spine) and builder-to-customer, they can convey their take on the benefits of doing so as a feature/benefit of the custom build. Production rod builders, and in particular, production builders who's rods are bought off dealer's shelves do not have that opportunity (or to date, their marketers haven't been clever enough to convincingly showcase the feature and its benefits.) Therefore it's wise for production rods to be built with the guides oriented to the straightest axis and in a manner that causes the built rod to appear as straight as possible when pulled from the rack and sighted from handle to tip like a rifle in it's respective cast or spin configuration. We've all seen folks do it at Cabela's etc. The exact same thing can be said for spiral wrapped rods. These features have a history of making appearances on off-the-rack rods and resulting in failure due to a lack of convincing marketing/available product info at the POS, a lack of dealer education, you name it.

-Geoff

Evan Cobb Wrote:
-------------------------------------------------------
> Tom Kirkman Wrote:
> --------------------------------------------------

> >
> > 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
> >
> > ..............

> Evan Cobb Wrote:
>
> Yes, that is what I meant.. Mr Loomis suggested
> placing spinning guides along the stiffest axis,
> and casting on the opposite side to balance the
> effort/energy and improve rate of return.
> Regardless, still the opposite of what most
> companies suggest and what I’ve been doing,
> which has been placing spinning guides on the
> inside of the curve (or softest axis)



Just keep in mind that the stiffest and softest axis are rarely 180 degrees opposite each other. Building on the spine is fine, but also keep in mind that doing so reduces blank strength and rod speed by a bit.

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

One thing I'm curious about is how this Fenwick with the spine misplaced fished? Sounds no one considered that the rod was deficient until the spine was found off the traditional position.

". . . reduces blank strength and rod speed by a bit." Tom, do you have data supporting the "speed" reduction? I presume you mean recovery speed.



Edited 1 time(s). Last edit at 05/10/2023 05:02PM by Michael Danek.

"reduces blank strength and rod speed by a bit" Tom, do you have data that supports the reduction in rod speed? I presume you mean recovery from deflection?

I am sorry. I am taking treatment for cancer. The pain is bad at times and the medication makes me stupid and tired. It's better than taking the pain. Rod building keeps me busy and takes my mind off of everything. If I survive I am going to Florida to go bass fishing. I can't even explain the stupid things I have done. I lost all my chargers to my chargers' to my battery operated tools. God what is next?

Everything I have read tell how to find the spline and how to place them on top or the bottom. I see spine finder at Mud Hole catalog page 185. I made one in my shop. The two bearings were expensive. Now I find out this is not important .Thank you everyone for your input. I am just starting. My skill level is below an armature.

Not everything needs data to back it up, a lot of it comes down to basic common sense .

A blank deflected by a certain amount on it's softest axis is not going to have the exact same recovery speed of a blank deflected by the same amount on it's stiffest axis .

Sam Kirk Wrote:
-------------------------------------------------------
> Everything I have read tell how to find the spline
> and how to place them on top or the bottom. I see
> spine finder at Mud Hole catalog page 185. I made
> one in my shop. The two bearings were expensive.
> Now I find out this is not important .Thank you
> everyone for your input. I am just starting. My
> skill level is below an armature.


Hang in there Sam , very sorry to hear about your health and wishing you the best outcome possible . Thanks for the laugh with the " Made my own spine finder and now I find out it doesn't matter" comment lol.

Sam my friend I wish you the best, hopefully you have a full recovery. In the meantime please stick around and continue to ask questions, the dogs don't always bite on this block.

As for your spine finder - if you have a blank that is already totally straight then it might as well build on the spine. Whether you build with the spine inside out or upside-down do some experimenting and discover for yourself if it's worth it or noticeable - some people will never build on the spine and some people will absolutely always build on the spine and some people are invertebrates.

Maybe we're all full of crap, but maybe you'll feel what Gary feels or Tom feels and it'll make you feel something - build whichever way makes you feel good.

Building rods in MA, Building the community around the world

Michael Danek Wrote:
-------------------------------------------------------
> "reduces blank strength and rod speed by a bit"
> Tom, do you have data that supports the reduction
> in rod speed? I presume you mean recovery from
> deflection?


Yes.

...

chris c nash Wrote:
-------------------------------------------------------
> Not everything needs data to back it up, a lot of
> it comes down to basic common sense .
>
> A blank deflected by a certain amount on it's
> softest axis is not going to have the exact same
> recovery speed of a blank deflected by the same
> amount on it's stiffest axis .


That is obviously correct. But you can prove this if you wanted by something such as Mike's TNF measurement.

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

I make golf clubs as well as fly rods, strictly for fun and my own use. I have tested rods on a table top by flipping them to find the "spine." I have built a spine finder with tube and bearings. Spine finders are also used with golf shafts by some club makers.

The straightest axis approach can be determined by 1) looking down the blank; 2) rotating the blank between two points a foot or so apart and look for the tip's high point, or 3) by doing number 2 but adding a bit of weight on the tip to help accentuate the difference.

Both spine and straightest axis methods are an approximation or trying to determine the rod's strongest axis, and each has somewhere between a small to a pretty large margin of error. In communicating on this subject with one of the world's premier fly rod companies designer, he employs the straightest axis method.

What I have found in the quality, four-piece fly rod blanks that I purchase, is that they are made pretty darned straight to begin with, and I doubt orientation matters much at all, particularly in the lower three sections of the blank.

The best scientific/technical way to find a steel or graphite tube's orientation, as the tube is never round but slightly oval, would be to use a laser, which is done in golf, to measure that shaft/blank's "flat line isolation," which finds that most "stable plane," which will sometimes only be a few degrees off from the spine, but other times will be quite off. Here are two good videos on how this is done with golf shafts, be they steel or graphite. So the outcome and results would be similar in rod blanks.

[www.youtube.com]

[www.youtube.com]

While a small industry has been built around FLO of golf shafts, and most pros use FLOed shafts, there is really no authenticated scientific study that proves it makes a meaningful difference. Most feedback is anecdotal or subjective, or biased by those who own the technology, or philosophically related to beliefs in physics.

My point, until a laser method of measuring a fly rod's "flat line oscillation" is created, you can choose spine or straightest axis. I've done both, and I think straightest axis makes the best sense, BUT unless you have a rather curved rod or tip, especially in 4 piece rods, I am not sure it will make any difference to the angler or the rod's casting, especially when you factor into the equation the effect of ferrules, guides, wrapping and epoxy, and multi-piece rods.

Spine determines the blank's softest or weakest axis, not the strongest.

.......

Sam, If you need anything to keep you busy I have plenty of overstock I can send you,blanks, reelseats, guides,thread. I've always wanted to fish Florida for Bass also.My email is open, give me a shout. Stay well.

Dennis J. Danku
(Sayreville,NJ)

I've got a lot of respect for you Dennis

Building rods in MA, Building the community around the world

Michael Danek Wrote:
-------------------------------------------------------
> "reduces blank strength and rod speed by a bit"
> Tom, do you have data that supports the reduction
> in rod speed? I presume you mean recovery from
> deflection?


Yes. Yes to which or both questions? If you have data, what does it show? Significant differences? Minor difference? I am also interested in how the data were taken, the test methodology.

Yes, I ran the CCF on the blanks in different orientations in order to find the difference in rod speed. The strength issue was done by dead lifting to breakage on identical blanks, all first quality Saint Croix blanks of the same model. All of these tests were performed on the stiffest and the weakest axis.which as I have pointed out, are not 180° opposite each other.

…………..

On 6 different blanks of 3 models (graphite 6 1/2 foot blanks) TNF showed 4 did not have a TNF difference due to spine orientation, 1 showed 8%, 1 showed 3 %. Testing was done with a video TNF process which should be VERY accurate and not sensitive to any operator interpretation. Thanks to a very inventive and disciplined builder friend for the data. It is my opinion that even with the 8% blank, one would not be able to feel the difference in recovery speed due to spine orientation.