Read with interest what people are saying about the spine

I have trained as a rod builder and spent a lot of time thinking about this topic as I like to get things right and have an appreciation of fine details

A well made blank will have very tight tolerances in terms of the uniformity and thickness of the material.. this is obviously because blanks are rolled (manufactured) under extreme pressure

HOWEVER a short, powerful rod WILL accentuate any of this feel, and is thus best spine aligned.. And I would suggest it is thus on the plane it WANTS to bend to, i.e 90 degrees to the spine

On a very short precision fly rod I would suggest it MIGHT be better having the spine aligned either dead on or 180 degrees to the guides, this MIGHT help with casting accuracy, a LITTLE bit

BUT there is DEFINITELY a lot to be said for custom rod building, because with a custom rod you get a far higher quality blank ON THE WHOLE than anything apart from a very high end factory made rod

very high quality blanks are much nicer to use, more responsive, crisper, tougher and far more durable than cheap ones

When you think about it in more depth, if the spine could be either straight, uniform, wavering, bendy, or whatever, in reality it is an AREA of the blank that is slightly harder (NOTICE I DID NOT SAY STRONGER) than the rest of the blank

The only rods I have ever owned and not liked were some overpriced factory rods with a big name written on them which were dressed up and marketed as something they weren't. They were just lifeless cheap blanks in reality.



Edited 1 time(s). Last edit at 03/07/2017 03:36AM by Tommy Bee.

You are a right-handed caster you will naturally cast to the right. If you find the spine of the blank and place it at a 45 degree angle to the RIGHT of the guide train the added stiffness will bring your cast back to center-straight - in theory. That's the only way a spine alignment makes sense to me.

OK, I'll bite.

During more than 20 years I've seen exactly one, just one, graphite or bamboo blank (glass and especially s-glass is another discussion) that did not have a spine (or spline or hard vs soft side, etc.) detectable in at least one section, usually the tip section. It's there, and while it is not quantified, it nonetheless can be detected, can be described in relative terms (some are more pronounced than others), and is very real.

The quandary is what impact does the spine or spline, etc. have on a rod's real world performance. i argue it its existence means that it must impact a rod's performance, but that the impact is not quantified and that the unquantified impact certainly might be so small as to be essentially a non-event. I primarily build fly rods and have build rods spine up, spine down, and 90 degree offset and I can detect no rod performance differences for rods lighter than 8 weight. For 8 weights and above I think those rods built with the spine down (guides on the outside of the curve or on the outside of the curve or on the spine) do bring line off the water with a bit more authority, which is nothing more than a single builder's coincidental observations. At one time I suspected the relationship of spine to guide locations might be important to rod dampening, but I've no interest in spending the time and $s to explore this point.

What we don't have is an abundance of objective, quantified data to settle the issue. The absence of such data does not mean spine is not real and its impact on rod performance is truly zero.

Until I see data to make me believe the spine is in fact a non-event, I'll continue to fail safe and put fly rod guides opposite what I detect is the spine or most pronounced spine. If spine truly is meaningless, then I've wasted only a few seconds per build. In the meantime I'll snobbishly sleep well knowing I've done all I can to build the best possible.

I bought a few high quality blem blanks with the only issue is a slight but noticeable curve towards the tips. When I do the procedure to find spine the curve will make the blank want to rotate to the inside of the curve. I am going to build these rods either curve tip up or down and it won't be noticeable visually and mainly the fish certainly won't. Even blanks that look straight will have a slight curve when rolled on a flat surface. If the "spine" truly mattered we would have to build specific rods just for side arm cast left, right and only be able to fight the fish from the same side.

A rod blank does not want to bend on any axis. And it is the resistance to bending that makes it suitable for use as a fishing rod. Thinking that you're somehow protecting the blank by aligning the spine so that it will flex along the weakest axis ( [www.rodbuilding.org] ) is not only false, but exactly opposite of what you'd want to do if you want to utilize the blank's maximum deadlift capacity. And, of course, thinking that we cast and fish on a single axis is also false. It can't be done.

Orienting the spine in any given position does not stop nor even reduce rod twist. The lever arm effect of the guides will always trump any spine effect. All rods with guides on top will have a tendency to twist under load from a fish. All rods with the guides located on the bottom will be inherently stable under load from a fish.

We have the data and facts to argue against any supposed importance of "spine" and what it supposedly does or does not do in actual use. Those who continue to say there is no such data simply haven't bothered to read it, consider physics or perhaps remain unaware that it does exist, in spades. Conversely, there is zero data showing that there is any importance to orienting the spine along any particular axis. Most high end blank and rod manufacturers, in fact, build their rods on the straightest axis, not the spine. Given the cost of warranty replacement, it would not make sense for them to do this is there were any structural advantage to building on the spine.


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

Would having a blank aligned tip down make a more easier to flex "sensitive" tip or is this not much difference to tip up?

When I said earlier that I don't think it matters, I will build with the spine up, in case it does!

With the spine up/facing you/behind the side facing the water you COULD effectively and possibly be giving the rod more oomph and lifting power against a hard fighting fish

Where is the data about this please if any

I sincerely believe that the spine doesn't matter, HOWEVER it MIGHT, and I MIGHT be wrong so I will continue to build this way that I was taught

There is a school of thought that has many supposed ''highly expert'' backers from very high end rod manufacturers that building at 90 degrees to the spine, i.e allowing the rod to flex in its natural or comfortable poistion of easy flex aids accurate casting, but surely a rod for big critters is about the power, IF THIS MATTERS AT ALL (which many high end rod makers also believe it does not)

There is definitely a strong case to argue that the differences either way, here there or whatever are so minimal as to be imperceptible. A good test would be to build a very short, hugely oversized blank and use a machine to cast it dead straight, pull a dead weight on it etc. repeatedly then measure accuracy, pull strength, fatigue, twist, torque, wear on the guides etc. very pragmatically

I suppose a lot is down to how fussy (or anal)! you are, how much you give a (darn), and how much you want to understand something that is in essence very imprecise and theoretical..

Perhaps we should take more of a look at golf shaft manufacture, golf shafts are more extreme pieces of kit than rods, short, strong and subjected to very fast and extreme forces compared to rods.. obviously a golfers swing is nothing like a cast (even if it is done right which for anybody who has played that damned game is another story altogether)!

It is good to join the forum and I would be very interested to hear from anybody who knows where I can read more in depth on this subject. Even though I am a rookie I intend to take rod building very seriously.
I have spent a good few days already pouring over this odd and mythical subject and am running out of patience reading the same contradictory and confused copy on the great 'tinternet! So please advise me you wonderful knowledgeable passionate fellow fishing nuts!

PS

Here is a strange little theory for you to mull over:

Could it be possible that any rod built in a ''standard'' Spine UP manner (depending on where you live- in Europe the ''standard'' seems to be spine up or behind the guides, 180 degrees, and in the US I am picking up that the ''standard'' is weakest axis or ''preferred'' plane of bending)

OR, ANY rod built for multiplier reel use with the guides on top while playing a fish, will:

a) cast innacurately due to more torque/trying to settle into it's ''pop position i.e preferred/comfortable plane of bending
b) twist, torque and knacker both itself and YOU out more while playing a large angry fish (especially from deep)
c) weaken the hookhold and damage the mouth of the fish more due to this twisting and torque, while..
d) ONLY offer the PERCEIVED benefit of ''playing the fish against a ''backbone'' of slightly more strength??

I am beginning to think that certain US popular theory on this has got it right in that the guides should be built on the weak or comfortable axis and not on or opposite the spine itself

Thoughts please

David Miller Wrote:
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> Would having a blank aligned tip down make a more
> easier to flex "sensitive" tip or is this not much
> difference to tip up?

Doesn't work as a method of finding spine mate

Far and away easier to find spine with fat end of blank down, bending against a flat surface, holding one hand in the middle of the blank and the other near the tip of the section
You feel a very pronounced and definite ''bump'' when you hit the spine, and ''pop'' (settlement) when you find the preferred plane of bending

In theory this is a very easy thing to do

All you are doing by having the rod the way round you mention is making it harder

I can see what you mean though.. testing a built rod, right?

Well I have just this minute tested a built rod, I cut away the bottom of the grip and exposed the blank.. not advised on a very treasured rod but it is the only way to be sure. All I did was tape the grip up again.. PS the result was that I found the rod had been aligned when I thought it had not so it was worth doing, the grip and gimball muffle the test massively

No I was saying that most rod builders will align the rod with the tip curving up like Tom said. My question is how about reverse and does it make the tip essentially weaker being pulled down for bite detection.

You've lost me mate

I think you are talking about cosmetic alignment i.e rod straightness

Not my bag I'm more concerned about spine alignment and rod performance

There is no such thing as a straight fishing rod, pretty much impossible

How about you determine the spine of each section of a multi piece rod independently (they could differ) and then arrange the orientation of each section in the build so they cancel each other out? Of course this is impossible when building a one-piece rod.

What do you mean by ''cancel each other out''??

Straightest axis is what I am talking about when asking about tip curve down vs tip up. A curve in the tip will make the rod "pop" when doing a spine finding procedure but most rod builders and manufactures diisregard the spine anyways.If I took a wood rod that had a natural curve and pushed on the outside of the curve it will want to flip over which is physics but with a fishing rod we aren't putting direct pressure on the top of the curve and like Mr. Kirkman said there are the force applied from the guides.

I do find it funny when some folks are so concerned about the spine when it concerns to rod twisting but won't build their conventional bait casting rods spiral guide wrapped.

The softest and stiffest axis are not 180 degrees opposite each other.

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

Tommy: If one section has a measurable spine on the right make sure the next section has a spine on the right. Same goes for up and down. Of course this only goes if your goal is to neutralize the effects of spine, which I assume is the purpose of looking for it? Otherwise, make sure the spine of each rod section lines up with its adjacent sections.

If I happen to build on a blank that has a bit of a bend toward the tip, I will always build it so that the bend is pointing down.

I am not building it that way because I am worried about the blank being stronger or weaker in one direction or another. The blank will be fine, no matter how it is oriented during the build. I build it that way, because if the rod happens to get leaned against a wall, the blank will tend to self center. Also, I find that if the band just happens to be a bit more than a little noticeable, the bend just tends to be less obvious to the user with the tip of the rod drooping, rather than rising up.

But, with the very mast majority of today's new blanks there is generally a non existent bend in the rod, so it doesn't make any difference.

Be safe

It sounds to me like my original post was correct i.e that my tests twisting the rod in all directions with the guides and spine in all manner of placements and alignments and not noticing the minute-est squiffage of discernable feel whatsoever..

were 100% CORRECT!!

lol

But I will build with the bump at the back anyway



Edited 1 time(s). Last edit at 03/04/2017 09:19PM by Tom Kirkman.

You agreed not to use that sort of language when you registered. Please don't.

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

Tommy Bee Wrote:
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> You've lost me mate
>
> I think you are talking about cosmetic alignment
> i.e rod straightness
>
> Not my bag I'm more concerned about spine
> alignment and rod performance
>
> There is no such thing as a straight fishing rod,
> pretty much impossible


I'd offer that the orientation of the straightest axis of the blank, has just as much of an affect on rod performance as the orientation of the spine of the blank.

The concave side of the curve acting pretty much the same as the "soft" side of the spine. Both are going to seek the same position under load. Actually, I would think that the more rigid the blank, the more important the positioning of a curve in a blank becomes.

As far as the orienting guides in relationship to the spine versus orienting them to a curve in a blank goes ... if you're building the rod for yourself then perhaps cosmetics means very little. But if you're building rods to sell to other people, cosmetics play a very important role.

If I were buying a custom built rod and while sighting down the blank noticed the guides were wrapped without consideration to a curve in the blank, I'd put the rod down and look for another one. And that's not because I've learned that in this day and age the spine of of a blank has little importance.

It's because when I look down a fishing rod, I want it to look straight.



Edited 1 time(s). Last edit at 03/05/2017 04:22AM by David Baylor.