Thanks, David.

[www.rodbuilding.org]

Since our last discussion on potential to measure sensitivity using TNF I went into deep thought and referred back to my studies of barrel harmonics. If you look at the image you will see an oversimplification of harmonic frequency travelling through a raw blank. Where the wave crosses your zero point (midline) you will have minimal effect and where the peaks and valleys lie you will have the most effect. If you were to have a higher frequency these zero crossings would move to different positions on the blank. So in theory, where you sense the vibration is very important. AKA where your hand/handled components are placed. So frequency pitch alone isn't the full picture in sensitivity.

Also, this being an oversimplification, your frequency will not be so perfect as placing components will alter or tune the frequency. The CG can also have an effect on where the zero crossings because the CG will not be perfectly in the middle of the cone.

The goal in barrel harmonics is to make the zero crossing at the muzzle so harmonics have minimal effect on consistency. It is altered by tuning with a weight on the barrel in most cases. The goal in sensitivity of a rod would be maximizing the effect by making the spot where we sense the vibration to be at a peak.



Edited 1 time(s). Last edit at 10/13/2022 01:17PM by Aaron Petersen.

I don't mean to be snarky or negative, that is not my intent, but how do I use this information to make decisions on which blanks are likely to be more sensitive than others, and whether this guide set or that guide set adversely affects sensitivity the least? I suspect it will take sophistication and expensive equipment?

And how does this information direct a blank designer's work?

Michael Danek Wrote:
-------------------------------------------------------
> I don't mean to be snarky or negative, that is not
> my intent, but how do I use this information to
> make decisions on which blanks are likely to be
> more sensitive than others, and whether this guide
> set or that guide set adversely affects
> sensitivity the least? I suspect it will take
> sophistication and expensive equipment?
>
> And how does this information direct a blank
> designer's work?

Not taken snarky at all. I am an engineer so I take joy in the process, even if it is minor.

To be honest, someone who does not engineer or test just does it by feel. Trial and error.

The information at this level would be more for enthusiasts and the engineers designing blanks and finished rods. With a proper setup, a blank taper can be designed, components placed, and materials chosen in such a way that the most effect from a given frequency is tuned to be in the right spot based on where the engineer places the seat. Then when someone like you or the rest of the super majority of anglers handles the rod you will feel the difference.

Thanks, that is what I thought. And from what I have heard, St Croix just may have a setup like that. It would be interesting to know whether they use it to check on what they have done, or use it to lead/direct their design process.

It is my belief that TNF does a pretty good job of, when it's all done and the blank is designed and built, and even the rod completed, telling which is the most sensitive because TNF is proportional to stiffness to weight ratio, and sensitivity is, it has been argued for years, proportional to stiffness to weight ratio. So far the rods I have tested that have the highest TNF's are the most sensitive based on my subjective feel.

That geometry gets into it is shown by one blank of RX6 that I have that has a TNF that is normally in the range of RX7's and 8's. I use it for many things, among them finesse. It appears to me to be a very sensitive rod. Interestingly it is a 3 piece travel blank.

The point I keep emphasizing about TNF is that while it may be imperfect, it's pretty good. And it takes just minutes and no sophisticated equipment. I am going to demonstrate it Saturday so I wanted to check it out before doing that so I took a blank and tested it and had data in less than 5 minutes with essentially just a few seconds of setup time. Probably two minutes.

TNF is a measure of recovery speed. True or false? If it's related to a rod's sensitivity, it is through anecdotal evidence, and nothing more. It's conjecture

It's no different than David postulating that taper and blank thickness have an affect on a rod's sensitivity. No different at all.

Because there is no definition of sensitivity we cannot say what is related to sensitivity. Weight, length, power, and action have (or can have with CCS) actual definitions. If Mick thinks that rods with a higher TNF feel more sensitive to him, he is right. We can't argue with that. Now, if we wish to define sensitivity as recovery rate, or ability to transmit vibration, we can measure that and figure out what things on average make a blank more sensitive. It is interesting to me that we never argue about what makes a rod have more power or a faster action. It just does. So we can either pick a physical property that we define as sensitivity, or just admit that it is all subjective and we have different opinions. After all, you can't argue with me if I think a rod "feels heavy" or "feels light " you can only tell me the weight of the rod. So it is with sensitivity.

Peter, agreed. My little outburst above has to do with this whole "where is the data" thing that seems to be taking over discussions such as these. At least to me, it's like we must now prove, with supporting data, everything we say we believe.

It's becoming reminiscent of some not distant enough discussions where marketing claims could only be verified with hard data. And just like those discussions, it's getting old.

Peter Yawn Wrote:
-------------------------------------------------------
>... If Mick thinks that rods
> with a higher TNF feel more sensitive to him, he
> is right. We can't argue with that.

What?

In God we trust...all others bring data.

Why does everyone keep saying there is no definition of sensitivity?

"Why does everyone keep saying there is no definition of sensitivity?" Because for some reason TNF is a threat to their understanding of fishing rods. They need a reminder that from the first post on TNF I defined, for the sake of the TNF process and discussions, that sensitivity was the ability to feel a bite.

I later discussed other definitions of sensitivity and the fact that there is no direct, objective way of measuring sensitivity, whatever it is. I argued that TNF is proportional to the stiffness to weight ratio. Simple physics. I mentioned that many rod experts for many years have believed that both stiffness to weight ratio and the natural frequency of a blank/rod are related to sensitivity, the higher the better. I have admitted that TNF is not the whole story of sensitivity and that there are probably other and possibly better measures that relate to sensitivity. However, so far, all other methods have required sophisticated and expensive equipment. But TNF is easily and quickly measured with equipment most of us already have plus a free Android app.

Is TNF a measure of recovery speed. Of course it is. I have stated it many times before and it is obvious that if a blank has a higher natural frequency it will have a higher recovery speed. Simple physics. Not rocket science.

I have repeatedly stated that since we have no "sensitivometer" then there is no way to prove that TNF is a measure of sensitivity. And I've been clear that it is my opinion, based on SUBJECTIVE EVALUATIONS, NOT OBJECTIVE MEASUREMENTS, that with the rods I've tested the higher the TNF the higher the sensitivity. SUBJECTIVE

I agree that the discussion has gone far enough. But those who are disinterested could just ignore the whole thing instead of attacking it. For those curious rodbuilders who have ideas on the subject that they would like to discuss, my email is open. I'll check out now with the reminder that if anyone is interested in a simple, easy, repeatable, cheap, OJECTIVE method of measuring something that appears to be related to sensitivity, they can contact me and I'll send the instructions.

"Why does everyone keep saying there is no definition of sensitivity?" Because for some reason TNF is a threat to their understanding of fishing rods. They need a reminder that from the first post on TNF I defined, for the sake of the TNF process and discussions, that sensitivity was the ability to feel a bite.

I later discussed other definitions of sensitivity and the fact that there is no direct, objective way of measuring sensitivity, whatever it is. I argued that TNF is proportional to the stiffness to weight ratio. Simple physics. I mentioned that many rod experts for many years have believed that both stiffness to weight ratio and the natural frequency of a blank/rod are related to sensitivity, the higher the better. I have admitted that TNF is not the whole story of sensitivity and that there are probably other and possibly better measures that relate to sensitivity. However, so far, all other methods have required sophisticated and expensive equipment. But TNF is easily and quickly measured with equipment most of us already have plus a free Android app.

Is TNF a measure of recovery speed. Of course it is. I have stated it many times before and it is obvious that if a blank has a higher natural frequency it will have a higher recovery speed. Simple physics. Not rocket science.

I have repeatedly stated that since we have no "sensitivometer" then there is no way to prove that TNF is a measure of sensitivity. And I've been clear that it is my opinion, based on SUBJECTIVE EVALUATIONS, NOT OBJECTIVE MEASUREMENTS, that with the rods I've tested the higher the TNF the higher the sensitivity. SUBJECTIVE

I agree that the discussion has gone far enough. But those who are disinterested could just ignore the whole thing instead of attacking it. For those curious rodbuilders who have ideas on the subject that they would like to discuss, my email is open. I'll check out now with the reminder that if anyone is interested in a simple, easy, repeatable, cheap, OJECTIVE method of measuring something that appears to be related to sensitivity, they can contact me and I'll send the instructions.

"Why does everyone keep saying there is no definition of sensitivity?" Because for some reason TNF is a threat to their understanding of fishing rods. They need a reminder that from the first post on TNF I defined, for the sake of the TNF process and discussions, that sensitivity was the ability to feel a bite.

I later discussed other definitions of sensitivity and the fact that there is no direct, objective way of measuring sensitivity, whatever it is. I argued that TNF is proportional to the stiffness to weight ratio. Simple physics. I mentioned that many rod experts for many years have believed that both stiffness to weight ratio and the natural frequency of a blank/rod are related to sensitivity, the higher the better. I have admitted that TNF is not the whole story of sensitivity and that there are probably other and possibly better measures that relate to sensitivity. However, so far, all other methods have required sophisticated and expensive equipment. But TNF is easily and quickly measured with equipment most of us already have plus a free Android app.

Is TNF a measure of recovery speed? Of course it is. I have stated it many times before and it is obvious that if a blank has a higher natural frequency it will have a higher recovery speed. Simple physics. Not rocket science.

I have repeatedly stated that since we have no "sensitivometer" then there is no way to prove that TNF is a measure of sensitivity. And I've been clear that it is my opinion, based on SUBJECTIVE EVALUATIONS, NOT OBJECTIVE MEASUREMENTS, that with the rods I've tested the higher the TNF the higher the sensitivity. SUBJECTIVE

I agree that the discussion has gone far enough. But those who are disinterested could just ignore the whole thing instead of attacking it. For those curious rodbuilders who have ideas on the subject that they would like to discuss, my email is open. I'll check out now with the reminder that if anyone is interested in a simple, easy, repeatable, cheap, OJECTIVE method of measuring something that appears to be related to sensitivity, they can contact me and I'll send the instructions.



Edited 1 time(s). Last edit at 10/13/2022 10:06PM by Michael Danek.

Mick....You stated above, "I respectfully submit that we cannot measure sensitivity;"
When you make statements like that...how are we supposed to react? Just believe you?
Are we to take the stance of Peter and suppose "We can't argue with that."?

Just look at some of the contradictory things your posting:
"...many rod experts for many years have believed that both stiffness to weight ratio and the natural frequency of a blank/rod are related to sensitivity, the higher the better."

Then this...
"....then there is no way to prove that TNF is a measure of sensitivity."

Mick...take your time with your thoughts and formulate a clear concise white paper for peer review and then publish it.

My method is very unscientific but used by salmon and steelhead anglers for decades to describe sensitivity of drift rods, if I was drifting my sinker and bait through a hole trying to keep it drifting near the bottom and occasionally ticking the bottom the RX7 would be a 7-tick rod and the RX8 series, in general, would be a 9 or 10 tick rod as far as sensing the bottom.

"Just look at some of the contradictory things your posting:
"...many rod experts for many years have believed that both stiffness to weight ratio and the natural frequency of a blank/rod are related to sensitivity, the higher the better."

Then this...
"....then there is no way to prove that TNF is a measure of sensitivity."

The statements are not contradictory. The first states the opinion of others as I've read in their statements regarding sensitivity.

The second states that since we don't have a "sensitivometer," a device that objectively measures the ability to feel a bite, then it obviously cannot be proven that TNF is a measure of sensitivity. I furthermore have often characterized TNF as an indicator of sensitivity, or proportional to sensitivity, and have presented the statements as opinion. I have chosen my words very carefully knowing how others will mischaracterize them at every opportunity.

I challenge you , Chris, and any other readers to show me the device that can objectively, directly, measure sensitivity (the ability to feel a bite) as a ruler measures length. It will be nice if this device is inexpensive, quick, easy, and repeatable.

No doubt TNF is part of the puzzle, and likely a large part, but much like other tubular structures the frequency needs to be read at the right spot. I fish with my index finger on the blank above the seat. If I could tune a rods frequency to be at max value in the exact spot my finger lies...that would be ideal. I will experiment some once I get my new shop setup. I am going to try to tune a frequency on a blank. I have been working on micro strain gauges that can be data logged. Hopefully they work for something like this. Then there will be data. With values.

Here is where I stand on this ..... if my post before this one came off as an attack, it wasn't an attack on TNF. It a direct response to an earlier post where a member postulated that taper and blank thickness play into the sensitivity of a rod, Clearly a reasonable belief as taper affects action, and blank wall thickness affects weight. Yet this postulation was met with the response "How do you know. You have data?"

This isn't someone saying that the reason they haven't found any remains of dead Bigfoot is because they are inter dimensional beings. A person making a wild and crazy claim like that should expect to be asked to prove what they're saying.

Am I the only one that thinks it's more than reasonable to believe that taper and blank thickness are factors that could play into a rod's sensitivity? Where is the data that says it doesn't? Have those factors ever been taken into consideration in any testing of any kind? I mean, those factors affect how a rod fishes. Surely their influence has to play a role in some kind of testing or another?

As far as TNF goes, it is not a threat to my understanding of fishing rods. I've spent time trying to figure out what factors of a rod blank may affect it. I've even asked if a blank's action has an affect on it. It was said that it appears to. So if action appears to affect TNF, and the taper of a blank affects its' action ....... why the "How do you know? You have data?" response when a member mentions taper affecting rod sensitivity?

I don't know ..... all I know is objective data doesn't always mean or prove what we think it might. If it did, shouldn't the entire eastern seaboard be under water by now?

David Baylor Wrote:
-------------------------------------------------------
>> ...
>Where is the data that says it
> doesn't?

David...The burden of proof is on the person making the claims.
One of the fallacies of debate is "an appeal to ignorance". Its a claim that something is true because it hasn't been proven false.

Mick....I have your device that measures sensitivity (with all your specs). I am in the process of writing a paper and documentation for it.
I think it will give us the data were looking for in some of the questions raised in this thread.
I don't think it's going to be much of a game changer...but we'll see.
One problem I see with any kind of measuring gizmo is this
Even though a certain model blank(s) can all have the same exact cut flags...none will be "exactly" made the same.
I see this all the time...the spine is different....the thickness of the butt. I can only assume that it effects other aspects (but I need the data).

Chris Catignani Wrote:
-------------------------------------------------------

> David...The burden of proof is on the person
> making the claims.

Chris, were this a debate between politicians where one candidate lobbed an accusation at another candidate, then yes, the burden of proof is on the person making the claim. If a marketing department for a rod manufacturer states that their rod casts further than another manufacturers rod, then asking or expecting them to prove it, is completely reasonable. But we're not talking about an accusation being made here. We're not insisting that a manufacturer proves the claims of their marketing department. In this thread and others, members have offered their reasonable thoughts on what might affect a rod's sensitivity.

Nobody,, other than myself, has made a statement in this thread that said their statement was fact. I provided a link to an experiment that I did dealing with the affects of adding weight to the butt of a rod, has on that rod's tip weight. The only reason I did the experiment back then and the only reason I linked it in this thread is because I made a statement that I classified as fact. If you make a statement and classify it as fact, then you had better be prepared and able to prove it, if asked to.

The only challenge to anyone I have seen in this thread, is the challenge as to whether or not a rod's sensitivity can be measured. Whether or not it can be measured depends on your definition of sensitivity. Every aspect that defines a rod's sensitivity can be measured .... except one. And that is the sensitivity of a rod while it is in the hands of an individual angler. And there is no amount of testing or objectively obtained data that can prove that, one way or the other.

Chris C posted something earlier ..... "In God we trust...all others bring data" Now I personally think he was making a joke, but I'd like to modify it to ...... In God we trust, in reasonable opinions we trust ..... all others bring data..

Touché Dave.

[waves white flag]