I’ve seen several people talk of placing guides on straightest axis of blank vs finding the spine. What are the pros and cons of each and why one way or another? Thanks

Johnathon,
Prepare yourself; you have just opened Pandora’s box / let the cat out of the bag. Keep an open-mind while digesting ALL the replies which are certain to follow.

Mark Talmo
FISHING IS NOT AN ESCAPE FROM LIFE BUT RATHER A DEEPER IMMERSION INTO IT!!! BUILDING YOUR OWN SIMPLY ENHANCES THE EXPERIENCE.

Straightest axis assumes your blank isn't straight, do you want to stare down at a crooked rod forever. Otherwise, it doesn't matter.

Spine would be the weakest orientation. Straightest axis is generally the strongest orientation. The two are rarely 180 degrees apart.

You may find this interesting: [www.rodbuilding.org]

..........

Johnathon

1. For me, the dead lift capacity or other performance loss is offset by the aesthetics of the finished rod. I cannot see dead lift capacity but I can easily see guides located in spot-on alignment.

2. I primarily build fly rods for which it is frequently very difficult to locate the spine of the butt or mid-butt section while the straightest axis is easily located.

3. For all we know it just might make little to no difference in rod performance regardless of guide orientation to either the spine or straightest axis.

@Jonathan welcome to the forum !

I'm new and still doing research - I trust the experience and expertise of Gary Loomis and here is what I found from him.

[youtu.be] at 1:30 he states that about 90% of the time if there's a bend it lines up with the spine anyway - then goes on to explain you should put guides on based on the spine and never mention ls being concerned about a bend in another direction.

[youtu.be] from 1:10- about 3:00

Looks like Gary has been building on spine for like 40 years based on these 2 videos.

Take @MARK's advice, everyone has their own thoughts on the matter and will respectfully share theirs. We may respectfully disagree, and like @SPENCER said at the end of the day it's your decision and the differences may very well be negligible anyway (like I just saw Donald said too haha)

Even Gary himself said (in other words) if you're building on the straightest axis then 90% of the time you're building on the spine anyway. You could even take the quick way and just build on the straightest axis because it's almost always the spine too anyway.

@TOM has great data, hard to argue against data haha. Tom, do you have any thoughts on the percentage of times the spine and straightest axis line up?

If you get a blank in that 10% where the spine and bend don't line up consider who your building for, if you're building to sell I can't tell you one fisherman who has ever even heard of a rod's spine - but they all look down the rod and check if the guides are straight. Your priority may change with that 10%.

Which really means that any contention over the years of straightest axis vs spine has been over about 10% of rod builds- we could probably call that not much of a big deal and nothing to get worked up about. Build how your comfortable and according to what makes sense to you, listen to everybody's input and weigh it all equally. Experiment for yourself and draw your own conclusions, then share your experiment and results with the rest of us so we can all grow and learn together.

Building rods in MA, Building the community around the world



Edited 1 time(s). Last edit at 01/20/2023 09:28AM by El Bolinger.

Simply put, this is a topic that is not worth arguing about.

You have a rod blank.

Orient the blank to please your sensibility - what ever that may be.

Enjoy the finished rod, or if building for others, let the others enjoy the rod that you have built.

Best wishes.

If I could I would click the like button on @ROGER's post

Building rods in MA, Building the community around the world

Welcome to the forum .
It's my understanding that building on the spine is a somewhat older convention and not as much in favor as it once was ( although there are several folks who still swear by the spine ). The link that Tom Kirkman posted above makes sense to me and , as Donald La Mar said , the aesthetics are much better when built on the straight axis . Because of these two things I will always go by Norman Miller's advice and build on the straight axis with a "tip up" orientation . But when all is said and done it is your blank and it will boil down to what ever cranks your tractor .
Ron

El

The spine is almost never, ever in line with the straightest axis. Start checking the blanks you build on and see for yourself. Keep in mind that what some people call the "spine" is really the stiffness axis, which is the straightest axis. The spine as defined by nearly all rod building books and authors is the outside of the weakest axis. This will almost never be in line or opposite the stiffest/straightest axis. Generally the spine and the straightest axis will be somewhere from about 90 to 179 degrees opposite each other.

It's also worth remembering that the issue of spine wasn't born until a particular book author coined the term and effect in the 1970's. And a few years later he flip-flopped and redefined it. To date there has not been any data or research proving that building on the spine contributes to more casting accuracy or less breakage. It remains only a theory.

........

So FIFTY plus years ago an insurance salesman decides to write a book on custom rod building and puts some stuff in it about rods having a 'spine' and what you should do with it. No data was supplied just an opinion of the effect. All these years later guys are still worrying over something that obviously makes no difference. It is amazing how things can grow all out of proportion if you just get enough people to repeat it over and over and across the years. Who wrote the first book on rod building? Herter's? Bullard? Pfieffer? I think I have read those and not a one of them ever mention rod spine.

Survey says: Straightest axis.

I'm a new rod builder so I'm not stating anything as fact, just different opinions I've read in my short learning journey so far. I've watched a lot of the "This is how we do it" videos at Flex Coat. They're pretty informative to me. One thing I picked up on from Roger Seider (I think that's his name) is that a lot of blanks have more than one spine. He recommended going with the more predominate one. He also said that if a rod has a bit of a bend in it, that he goes with that and doesn't worry about finding a spine. And, lastly, he stated that the spine isn't that big of a thing on lighter rods. Another guy named Gary Loomis said he doesn't know what the term spine is. If I understood him correctly, he said he just finds the natural bend. It seems like they're all pretty much stating the same thing, just using different terminology.

Again, I'm new, and defer all questions on the subject to experience builders, but as for my first build, I went with the "natural bend" of the rod as that made the most sense to me. And, since it's a casting rod, I attached the guides to the outside of the bend. Is that the spine? I guess it depends on who you ask. I must confess, however, my analytical (I'm a retired CPA) brain questions whether or not it makes a bit of difference, especially with today's blanks.

p.s. I am glad I didn't spring for the CRB "Spine Finder". I think I'd have been kicking myself if I had, and I almost did. Fortunately, IMO anyway, I rationalized my way out of it.



Edited 2 time(s). Last edit at 01/20/2023 04:04PM by Tom Kirkman.

I build on the straightest axis because in the end it "LOOKS" right.

Daryl Ferguson Wrote:
-------------------------------------------------------
> I'm a new rod builder so I'm not stating anything
> as fact, just different opinions I've read in my
> short learning journey so far. I've watched a lot
> of the "This is how we do it" videos at Flex Coat.
> They're pretty informative to me. One thing I
> picked up on from Roger Seider (I think that's his
> name) is that a lot of blanks have more than one
> spine. He recommended going with the more
> predominate one. He also said that if a rod has a
> bit of a bend in it, that he goes with that and
> doesn't worry about finding a spine. And, lastly,
> he stated that the spine isn't that big of a thing
> on lighter rods. Another guy named Gary Loomis
> said he doesn't know what the term spine is. If I
> understood him correctly, he said he just finds
> the natural bend. It seems like they're all pretty
> much stating the same thing, just using different
> terminology.
>
> Again, I'm new, and defer all questions on the
> subject to experience builders, but as for my
> first build, I went with the "natural bend" of the
> rod as that made the most sense to me. And, since
> it's a casting rod, I attached the guides to the
> outside of the bend. Is that the spine? I guess it
> depends on who you ask. I must confess, however,
> my analytical (I'm a retired CPA) brain questions
> whether or not it makes a bit of difference,
> especially with today's blanks.
>
> p.s. I am glad I didn't spring for the CRB "Spine
> Finder". I think I'd have been kicking myself if I
> had, and I almost did. Fortunately, IMO anyway, I
> rationalized my way out of it.


No, the spine is not the "natural bend" of the rod. If you read the article I linked to above, you will find that the axis of the blank that has the thinnest wall will tend to resist flex less than any other axis. Keep in mind this isn't a perfectly straight line - the "spine" is an effect, not a physical thing, and is created by varying wall thickness and other manufacturing anomalies. It is not usually found on the blank's straightest axis, which is usually found along any natural bend or curve in the rod blank.

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

Building upon the spine was started when fiberglass rods were fairly new, and they had more prominent spines. Also most were one or two piece blanks. Even then it was questionable whether it had any effect upon casting or landing. In short, it's old school!



Edited 1 time(s). Last edit at 01/20/2023 07:28PM by Phil Erickson.

This should keep you busy. Lol. [www.rodbuilding.org]

First off, thanks to everyone for the warm welcomes and all of the interesting responses. I’ve been setting on a couple of blanks debating on which way to start off with these and from the conclusion I have drawn I think I may actually try one each way. They are identical blanks so maybe by doing this I’ll be able to see what style is actually right or wrong for me.

I turn the blank till the tip reaches it's highest point, this will be the top of the blank.

I never find the spine before building a rod. However, I did once get an ultralight blank that had an extremely obvious spine. If I bent the blank in my hands it absolutely jumped until I was bending it along the spine. Is this a sign of a less well made blank? I've never had a blank like that before or since, but I just couldn't bring myself to build on it. I felt that if the effect was that strong it might effect how the rod behaved while fishing. Am I nuts?