How much of a rod can you wrap? At what point does it affect the performance of the rod. Could you wrap all the way to the tip?
Thanks for your help!!

Any and everything you add to a rod will undermine performance/efficiency. How much so depends on how much you add. Each item or even each wrap of thread is extra weight that your rod now has to carry. What happens to the performance of you car as you add each additional pound of weight? An extra trim wrap on each guide isn't likely to do anything you'll really notice, but if you get carried away enough, you can certainly change the way the rod performs just with extra thread and finish. Did you read Emory's article in RodMaker where he tested the RF of rods with various guide and thread set ups?

The supposed stiffening effect of guide wraps is another one of the long held rod building myths that started long ago. If you take a rod blank and wrap it, butt to tip, with thread. The blank will not become stiffer. It will act softer or less stiff as it now has to carry more weight. Add finish and the effect is even greater. I've even heard of guys who believe that adding stiff, double footed guides will stiffen a blank. Not so. They add weight and the effect is to make the blank act softer and certainly to react and recover more slowly. One local builder wanted to argue this so we took a Lew's graphite blank, 7' and pretty darn stiff (flipping stick) and wrapped it with the old ultra-stiff Fuji SHG guides from the foregrip to the tip. Where one foot ended, the next began. The resuilt was a very heavy rod that flopped around like a green tree branch.

If you're wanting to add more glitz to the rod, I'd stick to butt wraps, handle stuff, etc., and leave the upper 2/3rds of the blank as bare as can be. Keep the guide wraps short and finish no heavier than it has to be.

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

Michael,
I could not agree with Tom more. There is one additional point that you might want to consider when wrapping your rod and thinking about how it affects performance. As near as I have been able to determine the affect on rod performance of added weight increases exponentially from the butt to the tip. In other words a little extra weight added toward the butt of the rod, like a decorative wrap, will not have a major affect on performance but that same weight added toward the tip of the rod can have a dramatic effect on the rods performance.

I was watching a fishing show yesterday where a guy said that he likes "a medium action rod with a soft tip", I think he said for pitching. I'm not really sure how/what he meant by a medium action with softer tip? But from the above discussion will extra, decorative, wrap on the top guides or tip-top 'soften' the tip?



Edited 2 time(s). Last edit at 02/13/2006 11:55AM by Steven Libby.

Steve,
Weight added to the tip has a number of undesirerable effects. It will slow the rod down, not in its action but in its speed (it lowers the resonant frequency) it also increases the time it takes the rod to damp out vibrations and lowers the rods efficiency (stiffness/weight). The rod will feel less crisp and responsive and have lower sensitivity or feel. Some Bass fishermen like the slow reacting rods for crank baits but there are better ways to achieve this then by adding weight to the tip of a rod and turning a nice rod into a club.

Sorry, double post.



Edited 1 time(s). Last edit at 02/13/2006 12:12PM by Emory Harry.

Steve,

Most likely what he meant to say was that he liked a medium power rod with a fast action. Many fishermen badly misuse the term "action."

If you want to see what extra weight will do on those tip-most guides, take some lead wire (fly fishing shops will have it) and just wrap a very few strands around the wrap on the rods you have now. Just the last 4 or 4 guides is enough. Won't take much to quickly illustrate just how much it will changet the way the rod reacts and recovers. Try it and see for yourself. Don't add much, just a couple or three winds per guide.


........

"How much of a rod can you wrap?
At what point does it affect the performance of the rod.
Could you wrap all the way to the tip? ..."

Tom Kirkman & Emory Harry have given us a verbal description of the complicated relationships between these variables. For those Readers who wish to look at some equations that describe these relationships, so that you can strengthen your intuition with a mathematical expression, please read on.

There are two models that seem to properly approximate a fishing rod: the Pendulous (Hanging) Spring; and the Cantilever (supported at one end only) Beam.

At this stage in my understanding, I only have equations relating these variables to Resonance Frequency. Dynamic equations for force-deflection (loading) or forward-thrust (casting) or rod efficiency are not within my purview yet. Rod performance by these realistic criteria is harder to describe, evaluate or calculate. If it were simple, you would have read about it a long time before now. (and maybe you have, …) If it were not for our Emory Harry, Mike McGuire and Mark Gibson, I may still be wondering where to find equations for this information. (They are the ArchBishop and Bishops of Canti-Lever, respectively, as far as I know, at RBO. I guess that makes Bill Hanneman the Cardinal of Canti-Lever? …)

For the Hanging Spring Hanging Weight Model of the end of a rod beam: Imagine a spring hung from a ceiling. A weight (M) is added by hanging from the free end.

FREQ = [ 1 / ( 2 * PI)] * SQRT [K / (M + m)]


For the Cantilever Beam Model of the free end of a rod beam: Imagine a horizontal beam fixed at one end, with additional weight (M) at the free end:

FREQ = [ 1 / ( 2 * PI)] * SQRT [(3*E*I) / ((M + m)*(L*L*L))]


where:
RF = resonance frequency (1 / sec)
Pi = 3.14159…
K = spring constant (mass / sec / sec)
M = point Mass of the added weight (line guide, thread, finish, tip-top)
m = intrinsic mass of the rod blank itself (spring or canti-lever beam)
E = elastic modulus
I = cross-sectional shape of the beam, factor
L = length of the beam (at the location of the new point mass)

For those Readers who know how to read equations, and can understand the effect of a change in the magnitude of one variable on another, further explanation is avoided. For a given rod blank, M (guide mass) and L (guide location from the reel seat) are the only rod-builder adjustable variables. …

For those Readers to whom this is all Greek, Tom’s & Emory’s explanations offer the basic conclusions we are after anyway.

The performance-robbing design error of using over-weight guides (relative to the mass and power of the rod blank) is magnified the closer you get to the rod tip. RF is a convenient indicator of rod performance. I don’t know how RF directly relates specifically to a kinetic energy analysis of rod-efficiency.

PRE-LOADING the rod tip with over-weight guides and thread and epoxy will: decrease the resonance frequency; lower the rod’s lure rating (both the lower & upper limits); lower the modulus; dull sensitivity; increase damping time; decrease casting efficiency, and increase angler fatigue. Pre-loading should be avoided.

In my estimation, …-Cliff Hall+++, Gainesville, FL-USA.
See “Guide Weight and Rod Performance” by Emory J. Harry.
EJH: RMM-8(3) for further discussion: Tables of Mass v. RF for rods

Cliff,
I have a couple of small arguments with your post. We all talk about the modulus of elasticity of a blank, and I am as guilty as anyone, and when we do we understand basically what we mean so it is not a problem but if we are going to be mathematically rigorous, as you seem to love to be, then actually modulus of elasticity is a property of the material that the blank is made of. The blank itself does not really have a modulus of elasticity. The modulus of elasticity of the material translates mainly into two properties of the blank, stiffness and weight.
I will go back and look but I am pretty sure that L in the second equation is the overall length not the length to the point mass and K (spring constant) is a function of distance and force not rate as you have defined it.

Emory - Addressing your three items: (1) On E, we’re both right. (2) On L, you're correct. (3) On K, you're mistaken.

(1): Yes the E (elastic modulus) is an inherent property of the material out of which the rod blank is made. I guess I was shifting boundary conditions and considering the “new” rod material to include the outer layer of over-wrapped thread, which would give a new net modulus lower than the original graphite’s modulus.

(2): L = length of the beam (at the location of the new point mass). Yes Emory, I have added the reference to guide location in a risky attempt to introduce the idea of a lever arm length for a point mass. By some approximations, all masses forward of that guide could be considered an additional point mass as well. Hence that idea.

(3): The UNITS of FREQUENCY are (1 / sec). Since the radical of the Square Root function (SQRT) must render a result whose units are also (1 / sec), therefore the units of K (the Spring Constant) MUST be (mass / sec / sec), so that when K is divided by (M + m) mass, the radical's units will be (1 / sec / sec). The units of the period component of the product [1 / (2*Pi)] are UNITLESS. Therefore the UNITS for the RF ALL are found INSIDE the SQRT RADICAL, and those units MUST BE inverse SECONDS SQUARED (1 / sec / sec). ... [Perhaps some confusion has come from the flattened form of the equation and all those parentheses!]

As further proof of this fact that the units of the Spring Constant K are indeed (MASS / TIME / TIME), I refer to two classic equations for force in ordinary physics:
Force against a Body: F = m*a = mass * (length / time / time)
Force against a Spring: F = K*D = (mass / time / time) * length
where:
F = force
m = mass
a = acceleration
K = spring constant
D = displacement
For the units of force to be consistent in both equations,
the units of K must be (mass / time / time). … Q.E.D.
-Cliff Hall+++, Gainesville, FL-USA*****

Cliff,
I am sorry but I think that you are mistaken. I just looked it up on the web and k (spring constant) is defined as being equal to the force divided by the distance. By the way it is small k.

Yes, Emory - Small k for the Spring Constant is correct as the customary symbol. I used a Big K because it is easier to read on this website's text, IMO.

And you are correct about the units of k. They are indeed "the force divided by the distance." ... But now, Emory, you have proven my original correction. Because when a force (kg*m/s/s) is divided by a distance (m), the resulting units are (mass / time / time). Now we are both agreed. The units of k could be N/m (Newtons/meter) or kg/s/s (kilogram/sec/sec), which is suggestive of an acceleration rate, as you described it earlier.

Emory, this misunderstanding has more to do with the limits of communicating on such a Forum than anything else, IMO. ... No hard feelings, I hope, ... none here.

I apologize if I seemed so dogmatic, but that is because I only write what I am able to demonstrate. So, substantial refutation is usually precluded from the word "Go!", unless I make a typographical error. And I check very carefully for errors in content, grammar, punctuation, logic or typography before Posting on such a complicated Subject and Text as this one. Especially one involving equations, rod component facts, data, or citations. ... I do not want to mislead anyone, and I do not want to be misunderstood. That really wastes our time.

Best Wishes, my friend. ... Shalom, Emory. -Cliff Hall+++



Edited 1 time(s). Last edit at 02/15/2006 01:31PM by Cliff Hall.

Cliff, I have no fear of MIS-understanding you, my problem is in Understanding you!!! LOL!

Mike

Cliff,
I see absolutely no reason for there being any hard feelings so do not worry about that. After looking it up I now see where the disagreement or the misunderstanding between us is and that is that there are multiple definitions of the word force.
There is a DYNAMIC definition, force being the agent that causes a change in momentum, with the formula f=ma. Obvious that is how you were using the word and I would certainly agree with your previous statements if that is the definition that I was using, but it is not.
There is another STATIC definition, force is an agent that produces an elastic strain, force=stress/square inches. This is how I was using the word and using this definition I would go back to my original disagreement with you.
I guess that the important question is, in the formula for k (spring constant) is it the dynamic or the static definition of force . I would suggest that in the formulas for resonance it is the static definition.
By the way, I looked this up in Van Nostrand's Scientific Encyclopedia not on the net.

This also means that when we measure the power of a rod or blank using the CC System what we are measuring is actually the spring constant of the rod or blank.

Again it is just a friendly and I think interesting disagreement and there are certainly no ruffled feathers on this end.

Hey, Mike - Thanks for letting me know its being read,
by somebody besides just me and Emory, ... LOL, ...
even if it's just so much ... blah, blah, blah, ... -Cliff+++