I'm trying to wrap my mind around this after playing around and hoping a few of you engineering types can help -

Most methods of measurement use a set standard for deflection.
Two rods can measure out at the same point with the same weight.

Here's my dilemma... How do you measure how the blanks loads?

Bill Stevens' photo (http://www.rodbuilding.org/photopost/showphoto.php/photo/9985/cat/500/page/1) may help explain what I am getting at. These two blanks are deflecting very closely at that measurement. The AA is different as well as how the blank loads.

But I'm sitting here thinking, I could load up two blanks, have similar AAs, similar deflection weights, but have totally different "loading", flex point, etc (choose your method of description) and those blanks are going to perform differently although at a set point they may have numbers that are very close.

Also, what if you measured and deflected at different points? Couldn't two blanks that measure the same at the "set" deflection point have very different characteristics on the way there?

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To determine how a blank loads, one must make more than one measurement.
Consider the CCS and the URRS. These systems use three points in an attempt to better describe how a rod loads.

The measurements are made for ERN, TP, and PR. Many rods can have the same value for ERN, but the TP and PR values will probably differ considerablly.
For example, rods described a 2:5:9 and 4:5:8 both have an ERN of 5 but they load entirely differently.

Dr Bill - Thanks for the reply and probably comes back to some of my earlier struggles with TP/PR and not putting the whole picture together.

On a side note: I noticed North Fork (them going out on a limb again with publishing CCS data - no harm intended by this comment) doesn't show the TP or PR numbers. Any reason?

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Quite right Alex.
Two completely different springs can have the same deflection characteristics at one pont and be completely different at others. Depends on where the blank tapers are positioned.

Companies have to decide how much information they believe is necessary in order to help their customers select the proper blank for their desired task. They have to balance the time it takes to record all the various measurements versus how their broad customer spectrum values such measurements.

North Fork is already way ahead of the curve by offering the industry's only across the board power and action figures. The best anyone else has done so far is to offer across the board length measurements. North Fork may add PR and TP numbers at a latter date, or not. They're pretty busy just getting blanks designed and tested at the moment.

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Correct me if I am wrong, but wasn't the original premise of CCS intended to give us a means of comparing blanks so that we could obtain a blank from one manufacturer that is very close to a particular blank by another manufacturer? This thread seems to indicate that we would have a good chance of getting poorly matched blanks.

You're mistaken. The intent of the CCS was simply to put quantifiable and relative power and action figures on rods and blanks - something that had never been offered prior to the advent of the CCS. Obviously it does that perfectly.

As far as obtaining identical or very similar blanks from one manufacturer to the next, the only way to do that is to put as many numbers together as possible, and this would include not only power and action figures, but also length, weight, weight distribution, material, frequency, etc. The more numbers that match, the closer you'll be.

The CCS numbers do the same thing as length and weight measurements do - provide relative measurements. It's up to the rod builder to take the data/measurements and use them wisely for the purpose at hand.

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Mistaken?

Quoted from Rodmaker Volume 12 - Issue 4 page 26 - preface.

"If you wish to objectively measure power, action and/or speed in order to make relative comparisons between different rods and blanks, the information in the following brief article will allow you to do just that."

Ditto on that. There are a lot of aspects that have to be matched in order to make sure you would get a nearly identical blank from one maker to another. But the more information you have the better off you will be.

The advent of things like PR and TP in the CCS make it even more valuable for comparing blanks. Before all we did have was just length and sometimes weight. The power and action labels in the catalogs did not translate from one blank maker to another. So now we have...

length
weight
material - IM6, 7 whatever
ERN power
AA action
TP tip power
PR power reserve
CCF frequency

The CCS has given us a TON of new useful measurements if you want to take the time to use them. Only thing left would be weight distribution which is no doubt a very important thing when looking for an identical or nearly so blank. But I cannot imagine how that could be arrived at unless it would be at least partially covered already by the frequency measurement. I feel fairly certain that weight distribution would greatly affect frequency.

Bobby,

Yes you're mistaken. The quote you use does not say blanks with identical power and action measurements will be identical in all regards. In fact, we've said many times, both here and in the articles, that to get the exact blank, in every respect including "feel," you have to match more than just power and action numbers. I would have thought this would be obvious.

I can guarantee you that a blank with a higher AA has a faster action than one with a lower AA, and blanks with higher ERNs will have more power than those with lower ERNs. A blank with a higher CCF will possess quicker response and recovery than one with a lower CCF. And if the numbers match, those particular properties match. The system works and works perfectly - if it didn't we'd all be in really big trouble because our system of length and weight would be failing us as well.

To get an identical blank, you have to match as many numbers as possible, in as many areas as necessary. That's your job as a rod builder and today you have more tools at your disposal than ever before.


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Edited 2 time(s). Last edit at 11/27/2009 01:28PM by Tom Kirkman.

Peter,

Yes, the frequency, or the Common Cents Frequency, is affected by the weight distribution along the rod. A rod with a more weight near the tip is going to have a lower CCF reading than one with more of its weight closer to the butt. The material the rod is made from has a lot to do with frequency as well, but you're certainly correct about how that material (weight) is distributed along the rod.

The higher the CCF number the more rapid the response and the quicker the recovery of the rod will be.

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Using Eugene's comment:

How would you compare/measure blanks for how the action changes as it's loaded? Why - example ot a crank rod - it could exhibit one action while working the crank but another once a fish is on - this could be good or bad given the scenario or evenly highly effective knowing the blank could change. I'm guessing having to take measurements at different deflections - or that's what I come up with.

For Dr Bill:

I think I am confused on the 2:5:9 - I thought a rod with ERN = 5, TP = 2, PR = 9 would be written 5:2:9 based on the URRS article?

Could we safely assume (using your examples above) that the 2:5:9 rod would not flex as deeply as the 4:5:8 rod?

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The action doesn't change - action is a property which is measured in a single static position. This was true even before the Common Cents System came along. Action is "where the rod initially flexes." And this is the definition given by 95% of all the rod and blank designers who have ever lived.

So it doesn't matter if you're working a crank bait or fighting a large fish - the blank will still initially flex in the same place. A fast action rod remains a fast action rod, even when it's flexed back into the butt.

Any rod builder that's been around very long, understands that action is "progressive" - as the load increases, the flex in the blank moves from the tip towards the butt. Even a very fast action rod, with enough load applied, will flex back into the butt area.

It sounds to me like you're wanting to know something more along the lines of how far back the blank flexes with different loads on it. You'll have to simply take measurements with increasing amounts of weight to get that information. The rate at which the progression takes, however, can be reasonably arrived at by looking at the difference in taper between the tip and butt.

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How does one quantify: "where the rod initially flexes."

Take a rod blank and begin pushing its tip into the ceiling. Look at it. Where does it initially flex? In the upper 1/3rd? Then it would be labeled as having a "fast action."

The only problem with the old "fast, moderate, slow" rating system has to do very poor resolution. A lot of blanks initially flex in the upper 1/3rd of their length, so they're all rated fast. But some initially flex closer to the tip than others, which are also rated "fast." Same problem with "long, medium and short" and why inches and feet are greatly preferred for measuring the length of a rod blank.

With the advent of the Common Cents System, much greater resolution became available but the definition of action didn’t change - rods with higher AA numbers will initially flex nearer the tip than blanks with lower AA numbers. And this remains true even though the actual measurement is taken with the rod under a very extreme flex. Try it for yourself - take two blank with widely different AA figures and push their tips into the ceiling, noting where each initially flexes. The rod with the higher AA figure will initially flex closer to the tip than the one with the lower AA number.

All rod blanks, regardless of their action, will flex deeper and deeper towards the butt as the load is increased. The idea of Action, has always been to provide a “picture” of where the flex initially begins. Blanks with different actions will flex at different points when initially loaded, but put enough load on them and all blanks, fast, moderate or slow, will appear the same. They'll all flex deep into the butt area.


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The ability to quantify fast, moderate or slow is there, but takes some subjective means as there are going to be points where one overlaps the other and so no two builders may arrive at the same claim. This is another reason the CCS is so much better. Definite numbers beat terms and opinions any day! I do believe it is the future for all builders and manufacturers. Its just going to take a little time.

First: "where the rod initially flexes."

When a tip is pushed into the ceiling, is the direction of force kept parallel with the initial straight line that the blank made or is the force applied in a manner that would be directed thru the very butt and the very tip (in other words create a bowstring effect)? Neither case having any twist applied.

Or another option, does one simply apply a moment at the butt by twisting the hand to create the desired bending?

These three options make a big difference, which is why I asked the original question

Second: Parameters

Stated above: "...rods with higher AA numbers will initially flex nearer the tip than blanks with lower AA numbers." Does this now mean that we have come 'full circle' and are proposing that AA's given by CCS should now become a set of parameters used to define action?

It's not hard to take a rod blank and give it a flex and easily determine where the initial flex takes place - with such a wide space of resolution it's not at all hard to do. Any good rod builder can make a reasonably good judgment in this regard. But that's part of the problem with that system - poor resolution.

The CCS doesn't use such parameters - it functions just like your tape measure or thermometer. A board 6 feet in length is neither long nor short, but it is longer than a board 5 feet in length and shorter than a board 8 feet in length. Likewise, a blank with an AA of 65 is neither fast nor slow, but it is faster (initially flexes closer to the tip) than one with an AA of 55 and slower (initially flexes further back from the tip) than one with an AA of 75.


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I see what Bobby's getting at in how you bend your blank. You can force the blank into a bend that isn't totally natural and skew the results. But I think most would know if they are doing that or not.

If you are still using the old fast, medium and slow system, here is a surefire way to make sure you get the blank's natural initial flex. Hold it firmly about a foot or foot and a half from the butt end. Then smack or rap the butt end sharply with your free hand. Notice that the blank will waggle or wobble along its length. Note the point from which the tip moves back and forth. That is the natural point of the initial flex. It's pretty easy to tell if it takes place in the upper 1/3, or upper 1/2 or even behind that.

But having mentioned that I do feel the CCS is much better at determining which blank has a faster or slower action than another. It breaks things down into 30 to 40 points instead of just 3 or 5. Much easier to get the really fine comparisions with the CCS than with the old system.

Ken

Good point. I'll give it a try but I feel that it may still be somewhat subjective. I'm hoping someone has a quantifiable way of obtaining the action of a blank. Currently, the only way I can find that has been proposed (by searching the internet) is to graft load vs deflection over a wide range of loads and look for distinct changes in the slope of the graft line. Remember we are looking for the point "where the rod initially flexes".

My question remains: "How does one quantify: "where the rod initially flexes."