Norm,

Agreed, I recall the same conversations with Gary on Bamboo, Phenolic Resin, and Fiberglass blanks - there are so many variables that affect sensitivity of a blank, including the diameter of a blank, as the bigger the diameter, the more "vibrationally" sensitive the blank can be (outside of just the fact that more receptors on a hand are touching the larger surface area of a bigger diameter blank) but just like a bull-horn, a bigger diameter blank will amplify the vibration more.

I always chuckle when folks drop a blank on the ground, and try to tell what "modulus" the blank is by the higher ringing sound. The latter is a function of blank diameter and wall thickness, but it makes for some great marketing :D

Best Regards,
Aleks

Norman Miller Wrote:
-------------------------------------------------------
> Aleks, thank you for sharing the details on your
> research and development efforts. I really enjoyed
> reading about the new developments in antenna and
> fishing rod construction concerning sensitivity,
> and how one led to the other. I learned a lot.
> I’ve always been confused about the term
> sensitivity. Back when I started building rods
> there were no such things as carbon fiber rods,
> small light guides, or braided line. All we had
> were fiberglass rods with god awful heavy guides
> and components, and we used monofilament line.
> However, we were still able to feel a fish bite.
> There were times when the bite felt quite strong,
> other times the bite felt subtle, and some times
> we felt nothing and just saw the line moving. We
> bragged about how sensitive our rods were back in
> those days, but had no idea what made a rod
> sensitive. Fast forward to today. We have high end
> carbon fiber rods, much lighter components and
> braided line. The rods today are much lighter, and
> feel much better in our hands. However, even with
> these modern fishing marvels, some bites feel
> quite strong, others quite subtle, and at times we
> didn’t know we had a bite until we saw the line
> move. Seems like some things have changed and
> other things have not. Like many others, I’m
> convinced there are multiple factors involved in
> sensitivity or its perception. Some are objective
> and can be measured and others are subjective and
> much harder to understand. Fishing tackle has
> evolved quite a bit in my life time.
> Norm

Right off the bat, I thank Aleks for his openness and personal involvement in sharing this detailed information. This builds trust with me. I value that NFC keeps pushing the envelope and educating me along the way.

There are several themes going on in this discussion as I see them so far:

1.) A physics and engineering discussion.

2.) An anecdotal/personal experience discussion.

3.) A definition of terms discussion.

It's all great!

Aleks, thank you for this post and all you and your company do. I also think it speaks volumes that a manufacturer would sponsor a forum where it allows its competitors an equal voice. It shows a confidence in one's engineering prowess and product line while encouraging the idea that brilliant ideas can come out of "the mouth of babes".

Kendall brings up a lot of good/astute points.

Awhile back we used to have a bit of discussions on this topic. It is common to use measurements that are easy to obtain to "estimate" what you are really trying to measure. Recovery rate was often used to provide an estimate of sensitivity. Never mind that some were neglecting to factor in what a human's hand is capable of feeling:)

Anyhow, I thought I'd comment on the fact that a rod's sensitivity isn't only about detecting a bite. For a lot of my fishing there is no need to "detect the bite". There is though, a great need to feel what is happening at different stages in the fight with an oceanic pelagic fish.

In closing I like to say (IMHO) one should consider using an impulse for testing (rather than a sustained constant hertz). I'd like to see the harmonic breakdown of what is measured at the butt end.

Russ in Hollywood, FL.

Aleks,

thank you very much for sharing those observations. I would like to ask you kindly to address following issues:

1. is it the end of the 'slim' blanks ? In other words, would you agree that if we are looking for sensitive blanks then 'big taper' should be one of the cosiderations and we should generally avoid 'slim' blanks ?

2. would you still describe sensitivity as the stiffness / weight ratio after those experiments ? I have an impression that stiffness/weight is kind of a consensus (as for now) for sensitivity 'formula' - is it still valid in you opinion ?

3. there are manufacturers using fibers such as titanium, kevlar and boron in rod blank construction - have those metals similiar properties to nickel ? In other words, should we assume that use of titanium, kevlar or boron in rod blank construction generally increase sensitivity of such blank ?

Best regards,
Pavel

Build two identical rods - same action and power, same material, same handle, guides etc., but one a foot longer than the other. The longer rod will be more sensitive in real world fishing situations. It will have a lower stiffness to weight ratio, but it will be more sensitive. Its recovery time won't be as fast as the shorter rod largely do to having a lower stiffness to weight ratio, but it will be more sensitive.

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

A budget 10’ long fly rod gives an angler all sorts of feedback. When I pick up someone else’s five-ish footers (only my halibut rods are this short), they feel numb. I built a shorter rod than my usual selection to keep from slapping the water while working jerkbaits. It’s a minimal build on an SCV blank. It’s nice, but it doesn’t give quite the feedback of my similar, longer rods.



Edited 1 time(s). Last edit at 01/18/2023 02:50PM by Kendall Cikanek.

Tom Kirkman Wrote:
-------------------------------------------------------
> Build two identical rods - same action and power,
> same material, same handle, guides etc., but one a
> foot longer than the other. The longer rod will be
> more sensitive in real world fishing situations.
> It will have a lower stiffness to weight ratio,
> but it will be more sensitive. Its recovery time
> won't be as fast as the shorter rod largely do to
> having a lower stiffness to weight ratio, but it
> will be more sensitive.
>
> .................

Tom, it will be also heavier then. What you wrote is actually exactly opposite to what this board educated people for last 10-15 years.
I am aware of latest revelations by Emory Harry but I also remember tha E.H. at least once jumped to quick into conclusions regarding sensitivity issues ;)

Anyhow, my question was directed to Aleks because I am curious of his opinion in the light of recent experiments/measurements he described.

Best regards,
Pavel

The board is made up of individuals - it is not necessarily a consensus.

Emory Harry wrote an article for RodMaker many years ago. It was about sensitivity. I told him that he was wrong on the point of rod length - that a longer rod would be more sensitive. He built two rods and tried my test. He wrote a correction to his article and said that there was no doubt that the longer rod, even though it was heavier, was more sensitive. It changed his mind about sensitivity and what and how we feel things with a fishing rod.

Try the practical test - build two identical rods. Same action, same power, same material and same components. But one longer than the other .Now take any crankbait you like and retrieve it with both rods. Take a bullet sinker and drag it across your lawn with each rod. Pull a spinnerbait through the water with each rod. You will come to the same "revelation" if you want to call it that. I figured this out while I was in high school doing sensitivity testing in a friend's swimming pool, although it should have been obvious all along.

..........



Edited 1 time(s). Last edit at 01/18/2023 08:38PM by Tom Kirkman.

Pawel

There were blanks made with boron ( 80's-90's ?) and I built a number of pistol grip and spinning rods with the boron blanks. They were good blanks but for some reason cost, public support etc. they never became popular.

@John

there are still blanks being made with boron (and available for rodbuilders), that is why I am curious if Aleks findings regarding nickel may be true for other metals as well. This is very interesting because adding metal to the blank construction often results in weight increase. What Aleks wrote sounds quite revolutionary - especially that it comes from Loomis - that's why it is so interesing.

@ Tom

if I recall correctly, about 15 years ago EH wrote an article about sensitivity and the conclusion was that more elastic rod will be more sensitive. Which would correspond with longer rod being more sensitive. He then corrected this article here that in fact it is just opposite and more stiff / less elastic rod will be more sensitive. Has he changed his mind again ?
I used 9-10 ft spinning rods quite a lot, stopped and switched into lighter, faster, shorter rods for jig fishing. Garry's opinion about weigth and performance proved in practice.

Best regards,
Pavel

Pawel,

You have it backwards. When he wrote the article he said that a shorter, stiffer rod would be more sensitive. That was incorrect. After trying an actual practical test, he decided that a longer rod will be more sensitive and wrote a correction. Lever mechanics still rule the day.

.........

Hello All.

Here is the main "Sensitivity articles.

Vol/Issue...............Name...................................Author..................................Page....
10/1 Sensitivity (What is it? What makes one rod more sensitive than another?). By Emory Harry. 28
25/5 Sensitivity- A Practical Test By Tom Kirkman. 24
23/1 Sensityvity… By Tom Kirkman. 18

Good Luck.

Tight Wraps & Tighter Lines.

Bob,

New Bern, NC.

I would also add this tread from 2007 ;)

[www.rodbuilding.org]

Best regards,
Pavel

My purely anecdotal experience regarding rod length is that while longer rods are indeed more sensitive, there is a point of diminishing return.

For me, the tipping point seems to be about 8 1/2 feet. Meaning that a rod of 9 or 10 feet or more seems less sensitive than a rod of 8 or 8 1/2 feet.

My point of reference is a particular steelhead/salmon presentation where small crankbaits are moved extremely slowly, even simply hung in current. Intense focus on what the crankbait is doing is imperative, as fish often simply grab the lure and remain in place. After nearly 40 years of fishing and building rods to present baits this way, I've arrived at 8-8.5 feet.

I'm open to believing that this phenomenon is not a function of rod length, but more one of the practicalities of building long, light, balanced rods, and the resulting interpretation my hands make of bites, and the changes in the vibrations of the lure.

I'd be interested in the perspectives of anyone else that has experience with using rods of these lengths for presentations that require great 'feel".

Pawel,

Very good questions.

1. Yes, Boron is more sensitive than carbon, but two things impact why more of boron is not used in blanks. Reason number one is the cost of boron, and its use in wing panels of fighter aircraft. There is really one manufacturer of boron fiber - called specialty materials, but it is almost impossible to compete with the demand of budgets of governments and the like. Second is how it behaves in a laminate, and it is incredibly difficult to process and it really does not like being made into a tube - it only allows for one ply - which eliminates a lot of products.

2) Titanium - actually titanium is less sensitive than both steel and carbon (the modulus of titanium is 120 gpa, and the modulus of steel is 210gpa), but it its tube form (which is how it was used in blanks) it is much heavier than fiberglass (in short, the formula "lighter in weight, higher in modulus usually means "more sensitive") and less sensitive. (Nickel is on par with Steel).

Nickel is possible to vaporize at a lower temperature, steel and titanium are not, so you can't really vaporize them without damaging/degrading the fiber (the temperature is too high)


Best,
Aleks

Pawel Tymendorf Wrote:
-------------------------------------------------------
> Aleks,
>
> thank you very much for sharing those
> observations. I would like to ask you kindly to
> address following issues:
>
> 1. is it the end of the 'slim' blanks ? In other
> words, would you agree that if we are looking for
> sensitive blanks then 'big taper' should be one of
> the cosiderations and we should generally avoid
> 'slim' blanks ?
>
> 2. would you still describe sensitivity as the
> stiffness / weight ratio after those experiments ?
> I have an impression that stiffness/weight is
> kind of a consensus (as for now) for sensitivity
> 'formula' - is it still valid in you opinion ?
>
> 3. there are manufacturers using fibers such as
> titanium, kevlar and boron in rod blank
> construction - have those metals similiar
> properties to nickel ? In other words, should we
> assume that use of titanium, kevlar or boron in
> rod blank construction generally increase
> sensitivity of such blank ?

@ALEKS et all please share your thoughts on the link below.

[trika.com]

Link to testing process

[cdn.shopify.com]

Building rods in MA, Building the community around the world



Edited 1 time(s). Last edit at 01/21/2023 08:57PM by El Bolinger.

Cobalt has a slightly higher density to amu ratio… cost doubles but if it could be substituted the rod would be even more sensitive!

El, what are your thoughts on it? ........ the competitors weren't named. The specific rods from the competitors weren't named. The specific rods from Trka that were used for comparison sake, weren't named.

That should tell you something.

It looks like they are being tricksters to me ........

Tricksters? Trika?

Aleks Maslov Wrote:
-------------------------------------------------------
> Chris,
>
> It's a balancing act for sure - we roll our blanks
> under 250 psi, the industry standard is about
> 40psi. This means that we can do get a dense
> enough laminate with less resin in the material.
> Less resin means that you can put more of the
> "good stuff" in the blank (more fiber for
> strength, a scrim, etc.)
>
> I am not worried about someone trying to use the
> information above...I wish them luck with the
> learning curve, and our lawyers are pretty good.
> It is more for the annoyance of someone saying
> that they are using a "metallic" fiber in their
> pre-preg, even though they are not...in case that
> happens (and it will) you heard it here first :D
>
> Aleks


Aleks, thank you for your discussion on your research. I guess it must be obvious to everyone else, but help me understand how rolling a blank under higher pressure gives you a rod with less resin when the Resin in the scrim is solid when rolled?

The pressure remains and will force out additional resin when the blank is "cooked" in the oven. The resin liquifies during that process.

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