I agree, but if you have two blanks of the same length and "virtually" the same CCS numbers, IP and AA, they will not have appreciably different shapes under load. And they will not have appreciably different tip stiffness. If they have the same numbers and don't have the same loaded shapes and tip stiffness, the numbers have to be wrong. Right or wrong?

Too bad ERN had to get into the discussion; it's just a "conversion," a derived number to help fly rod users correlate a blank's power to what may be the right line. For all other types of rods we would be better just discussing IP. IMHO Great thread, will help us all get a better understanding of what's going on.

If AA and ERN are very close or even identical, then overall power and action will be very close or identical. But other characteristics may be very different.

ERN is a rod power number, not a line number. A rod with an ERN of say, 5, could fish equally well with fly lines from 3 to 8, depending on you and your fishing distance. ERN provides simple power number figures like Fenwick, Loomis, etc., have done for years, except it runs across the board, isn't limited to one manufacturer and has a standard behind it. So instead of 1-power, 2-power, etc., you have ERN-1 or ERN-2, etc.

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Tom, your last post is exactly the point I was trying to make in my earlier post. I haven't delved into the CCS beyond the "Big Picture", but I can see how it would fill in the parts of the picture that simply checking for IP, and AA would leave blank.

Michael, I'm not poo pooing CCS entirely. I'm just saying that CCS AA and IP (or ERN) numbers don't tell the whole story. The Big Picture does. But to do that, you have to have the blank in hand.

Thank you to all for the continued replies to this topic; I have learned, and am continuing to learn quite a bit; including being guilty of previously comparing apples to oranges. Excuse me for substituting ERN for IP as well. It now seems to me that CCS can be as simple or involved as one desires it to be, or possibly “makes” it to be is more precise. CCF has barely been mentioned and I was surprised to learn many veterans rarely exploit its contribution to the over-all picture of blanks. Through my adolescent rod building eyes, CCF has a lot of merit. None the less, it is a true travesty Dr. Bill’s contribution of CCS, IP, AA and CCF has not been universally accepted and adopted across-the-board so as to be included or stamped on every blank or rod; what's wrong with the simple life?

Mark Talmo
FISHING IS NOT AN ESCAPE FROM LIFE BUT RATHER A DEEPER IMMERSION INTO IT!!! BUILDING YOUR OWN SIMPLY ENHANCES THE EXPERIENCE.

There is some advantage, according to many manufacturers, that blanks cannot be compared in all aspects across the board. They're sort of locked in to using inches and feet to describe length, and some will give you a physical weight for a blank as well. Beyond that, many prefer to use their own in-house system for things like action and power.

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"If AA and ERN are very close or even identical, then overall power and action will be very close or identical. But other characteristics may be very different." And the loaded shapes of the two rods will be VERY similar.

The best rod for angler "A" is likely not the best rod for angler "B". This is especially the case with fly casters. Rod builders can build to a user's specifications or to a user's actual needs. When "form" (AKA appearance) trumps function the rod builder's job gets easier.

I see my last reply came in after Tom and Michael's replies. My apologies for not addressing things more thoroughly, I was in a bit of a hurry when I was making the post, but I wanted to state that what Tom said about blank's having different characteristics, despite having the same IP, and AA numbers. And I use IP because I personally cam relate to it more than ERN. Anyhow .....

The example I am siting of two blanks with similar numbers having different characteristics. Before I go any further, I want to know if a 31 gram difference in IP is too large of a difference to be considered similar? If not, these two blanks have characteristics that I consider odd for their respective powers. The blanks in question are an NFC DS6107 IM, and an Rainshadow Eternity2 ETES610MXF. The numbers for the blanks in order of mention are, AA 77 with an IP of 387, and AA 79, with an IP of 346. I performed the tests myself, and tested them 2 different times. I tested them twice because in my initial testing I didn't have the blanks supported 10" from the butt of the rod. I had them supported on the blank just ahead of the reel seat which put the support 13 1/2" from the butt. The numbers didn't change drastically though, and the numbers I quoted are from having the support in its' proper location. I have a jig set up against a partition wall in my basement. I have a level line drawn on the drywall for the blank. and level lines drawn at various distances from the base level line that represent 1/3 of the length of the various blanks I tested. It's right against the wall so it is easy to see when the tip hits its' required point of deflection. I have the AA chart taped to a piece of pegboard and I put a small torpedo level on the bottom so I know the base is level, for checking the AA.

As I have an over abundance of worm weights, I just put those in a bag until I achieve the required amount of deflection, then I weigh the bag on my scale. I'd say my measurements are pretty accurate, but I would love to hear numbers from others if they happen to have the blanks mentioned.

The DS 6107 blank flexes deeply into the lower section of the blank, actually pretty much to the reel seat, yet it's a more powerful blank. The 610MXF blank doesn't flex near as deeply into the blank, but it has a much softer tip. And when I say much, I mean by quite a bit. Michael, their loaded shapes are not that similar. Even though it is a less powerful blank, the 610MXF has very little flex in its' lower 1/3, and it certainly doesn't flex to the reel seat. I am deeply disappointed with the 610MXF blank. I laid that rod out when I built it. Full length carbon fiber rear grip, KR concept guide train using Fuji T2 titanium guides with SIC rings. It is an absolutely gorgeous rod ..... that I very rarely use.

So anyhow ................I consider the numbers to be very close, close enough that they should at least act somewhat the same, yet they don't. At least they don't to me.

Carry on

David,
Thank you for your contribution as well. Please excuse my nit-picking. In your comparison of two “similar” rods, I get a difference of 387g – 346g = 41g, not 31g. None the less, 346/387 = .894 or slightly more than 10%; my novice eyes sees that as too much to be considered “similar”; possibly 2-3% would be OK. Your AAs = 77* and 79*; 77/79 = .974 or slightly more than 3% = more “similar”.
I am very curious to learn how slight (yes, a generic/relative term) of a difference in the above type measurements produces a noticeable difference in the characteristics of a blank. I am (still) here to learn.

Mark Talmo
FISHING IS NOT AN ESCAPE FROM LIFE BUT RATHER A DEEPER IMMERSION INTO IT!!! BUILDING YOUR OWN SIMPLY ENHANCES THE EXPERIENCE.

David,

No the blanks are not extremely similar. Keep in the mind the extremely high resolution of the CCS. The numbers you list for the NFC and the Batson indicate that the NFC model will be more powerful, albeit a bit slower in action than the Batson model. The Batson model will be faster in action, but less powerful than the NFC model. It appears to me, that the CCS was, as usual, absolutely spot on. In fact, your numbers are a testament to just how good the CCS is. (If you'll get away from IP and use ERN the difference in power is a lot more evident.) Beyond all this, something seems amiss with the numbers. Are these super ultra-light blanks?

One other thing - the forward support should be at a distance that is equal to 10% of the blank's overall length, not 10 inches.

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Since ERN is a "derived" number why is it better, more accurate, or more desirable to use than the "pure" IP number which is the actual observed power with no corrections or tweaking added?

From my experience I agree that the power of the two blanks is significantly different, not "similar." The AA's are significantly different also, but not to the same degree as the power. I used to use the same method of measuring AA and thought I was probably plus/minu 1 degree, maybe a bit more. I think now that I use a digital level there is very little error in reading the AA. An indicator piece taped to the tip of the blank is necessary, presume it's being used?

Never said it was better or more accurate (it's the same thing) but a simple whole power number is easier to employ. The average fisherman can look at a 4-power rod and a 5-power rod and most likely will get the idea that the 5-power rod is stiffer/more powerful, without needing any education into where the number came from. Looking at numbers like IP387 vs IP346 won't mean much to those that don't have a thorough understanding of the system.

Plus, with ERN no one can get the idea that it represents the amount of weight that a rod will cast - which has been the case with some who look at IP in weight and due to lack of understanding will assume it is the amount of weight the rod is capable of casting. I've gotten phone calls wanting to know why a rod broke when it was "supposed" to cast that much weight.

The idea of using common pennies as the weight standard and relaying that to ERN was intended to make the system easier for most people to use. ERN is the power figure decided upon by the inventor of the system, which should count for a lot. The simpler you can make something the more likely it'll be used.

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Got it, thanks.

Mark, thank you for correcting my math. How in the world I got 31 out of that is beyond me. lol And ok...... I'll go with the majority and say that they are not similar. In my defense, or more as an explanation ..... with the majority of the blanks I've built on thus far, 41 grams, or roughly 16 pennies, does not make much of a difference in how the blanks feel. As Mark pointed out, on blanks with the kind of power as the two blanks mentioned, 10% is quite substantial. When most of my rods have IPs of 800 or better, 41 grams isn't that much. Be that as it may, when I see as others have spelled it out in the manner it has. I digress.

With that said, Michael, we will have to agree to disagree as to whether the AAs are similar or not. I will definitely use 10% of the rod's length for my forward support in any future CCS tests I do.

And Tom, to your question are these super ultra light blanks. They aren't marketed as such, but they certainly are in my book. The DS 6107 is rated 1/8 - 3/8, and 4 - 10# test line. The Eternity 610 MXF blank is the one I am extremely disappointed in. Its' ratings are 3/16 - 1/2, and I believe it was 6 - 14# test. I built the Eternity blank as a replacement for the DS 6107. I fish Lake Erie occasionally for smallmouth bass, and I wanted something with more power for those deeper water fish. Despite what I expected because of their ratings, I ended up with a less powerful rod.

My experience with that blank actually has me scared to even buy a blank that I can't actually handle, or that I haven't already had experience with. I have a beautiful, extremely sensitive rod that I rarely if ever use.

Ah well ....... thanks for setting me straight on the blanks not being that similar guys. I guess my disappointment with the one rod had my head spinning a bit.

David, your disappointment in the power of the Eternity doesn't reflect a problem with the CCS process. CCS, done correctly, describes the blank/rod accurately, objectively. I have seen comments before that have indicated that the Eternities of that series have power ratings that are not consistent with builders' perceptions which, like yours was, were based on the SUBJECTIVE descriptions provided in the "specs."

Michael, you are absolutely without a doubt correct when you say I am disappointed with the Eternity blank based on what "I perceived it would be" based on the weight ratings listed in its' specs. It's not the first time I have been disappointed with a blank based on specs, or on what others have said about a particular line of blanks from a manufacturer. Luckily I was able to sell the rod I built on the other blank I was disappointed in, but if I sell this rod, I am going to end up taking a bath on it.

Anyhow ...... I'm most likely going to strip everything I can off the Eternity blank, and use the components on another build.

Thanks for the participation guys. Much appreciated.

David, you are making a really good argument for CCS. The more one uses it and understands it, the fewer surprises one has. Obviously, if the manufacturers, like Point Blank, provided it on all the blanks there might be no surprises. And no disappointments with respect to power and action.

Michael, I may be making a good argument for CCS based on how haphazardly manufacturers rate their blanks, but I still stand by what I said earlier and that is that I believe the type of blank also plays a role in how a blank acts and feels. AA and IP, or ERN numbers are going to paint a picture, but not the whole picture. For that you need "Big Picture" kind of testing to find out where the power is or isn't.

Everything is relative to something else. If you came here from another planet and were told that an item was 84 inches long, you'd have no idea what that figure represented. But you would quickly understand that 84 inches is longer than 65 inches and shorter than 100 inches. Over time, you'd get used to what the length of a single inch represents and could even better envision actual length in your mind's eye. So, too, with the CCS. Most understand that an rod with an ERN of 12 is more powerful than one with an ERN of 7, but what, exactly does one unit of ERN represent? Well, if you use the system enough you'll get it at some point. The best advise I can give people is to take their favorite rods - rods they really use and know, and measure them. From there you have a fantastic basis for comparison because you'll have a better understanding of what ERN and AA represent of their own accord.

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The major problem with using ERN, is that it is not a constant unit of measurement, it varies. Thus it’s not intuitive. A measurement of one inch is alway a constant unit of length and ten inches is always ten times longer, same is true with centimeters, ounces, grams, grains, cents or any other constant unit of measurement. ERN on the other hand is not a constant, or even a proportional, unit of measurement. An ERN value can’t be measured directly using a defined ERN unit. It has to be converted from a measured IP number, which does use a constant unit of weight, by looking it up on a chart or by using an ERN calculator. If you don’t have the chart or calculator you are out of luck trying to convert an IP measurement to an ERN value, and vice versa. For example, an ERN of 1 equals an IP of 14.25 cents, an ERN of 2 equals 20.46 cents, an ERN of 10 equals 82.1 cents and an ERN of 20 equals 231.03 cents. As one can see ERN is not a very logical or intuitive measure of power. This is my major problem with using an arbitrary and artificial ERN value vs a directly measured IP number. Just my thoughts, and the reason I report my CCS blank data as IP vs ERN.
Norm