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Is it possible to calculate the weight of a blank before building it just using the raw taper? I'm taking another run @ Vince M's. 9' 5 wt. sub 4 oz rod and want to know if I got the tapers close to what is needed. Weighing the other components is a snap as compared to figuring out the blank weight.

As cane weight varies somewhat + the weight varies depending on the size of the 60 degree piece, I would think that representation samples 1" long started @ 0.030 and increasing @ 0.025" of thickness to about 0.180 would yield enough info on the cane itself. But then, my math gets real fuzzy. (Don Anderson)

I also thought about this to include into my own taper calculation  software, but did not do so so far. First of all one should know the  exact specific gravity of a piece of bamboo strip, which should be  possible using a high quality lab scale.

I would predict that a series different size test pieces will be  necessary (pieces from a butt strip, midsection and tips) in order  to end up with a halfway decent result. I could imagine that the  specific gravity of a piece of bamboo strip can vary according to the  part of the rod it comes from. There certainly are variations from  culm to culm, according to the age, moisture content, etc. Something  to be done in a physics lab.

Anyway, next comes the math. If we are looking at a strip section  (from a 6-strip rod of let's say about 5" long) we are dealing more  or less with a frustum of a three-sided pyramid. To make things a bit  more manageable one could calculate the average cross section area of  both ends and multiply this by the length (e.g. the 5" mentioned  above) and we get the volume of that section.

Do this for all the other 5" sections and add-up all the values and  you get the volume of a strip. This result multiplied by 6 and you  get the volume of the rod. Then multiply this by the specific gravity  of bamboo (or do this in steps if there are variations according to  the size of the cross section and there is the weight of the blank.  Add a few 100 milligrams for the glue...

All this should also be possible with a raw taper. Then the specific  gravity of a piece of a rod blank should be determined the same way I  explained above, which means that a whole rod blank must be  sacrificed (cut to pieces). Hmmm, what a waste... maybe one should  give it a try to measure out a whole blank and weigh it on a lab- grade scale to arrive at an average specific gravity of a bamboo  blank...

Anyway, that's the way I would try to attack that problem. As I see  there is ample room for inaccuracies... One should give it a try with  a couple of rod blanks and the measurements of the finished strips to  see how accurate this method actually is.  (Frank Neunemann)

If you have a copy of Garrison's book, go to page 251. The formula for calculating the bamboo taper weight by 10"  segments should give you what you need without cutting up a rod. Garrison assumed bamboo weighed .668 oz. per cubic inch. Where he got the number, I've no idea.

.668xh/3x(A+A1+sq. root of A+A1)

Where:

h = 10"
A = area of one end of 10" section
A1 = area of other end  (Don Schneider)

This work has been done for you. If there still remains a way to access Wayne C's Hex96C version of Hexrod, it automatically calculates weight. Wayne was kind enough put it in there at my request, but apparently I was the only one who appreciated it, and it's not in subsequent versions as far as I know. The weights  calculated are theoretical, based on the .668 density, and become inaccurate as the volume of pith in the sections increase. As I recall, the calculated weights are about 10% high for trout rods. I can't make a working copy on my mac, and can't send it through the Mac even if I could. I do have it on floppy disc. Is anyone out there able to help Don?  (Tom Smithwick)

Take a look at page 251 in Garrison's book "A Masters Guide to Building a Bamboo Fly Rod". It shows how to calculate the volume of a hex rod section in cubic inches. Then use 0.668 oz/cubic inch for the density and you'll get the weight. For simplicity you might use a straight taper and you'll get close.  (Ray Gould)

I was pondering rod weight the other day after quite a few customers were asking about it and wanted to get some input from the list. The customers that asked own many older rods and have fished bamboo for many years.

Background

Makers used to use rod weight as a factor in determining line weight and rod action, etc. and routinely inscribed the rod's weight on the rod. My understanding and my empirical experience was to use the weight of the entire rod as finished but not include the weight of the reel seat/insert and grip, as these elements do not contribute (at least not substantially) to the action of the rod.

I then weighed some old rods that have the weight inscribed on them, and most indicate the actual weight (including grip and reel seat), with about 40% indicating a weight less than the actual weight which is, presumably, the actual weight minus the grip and reel seat.

My questions are:

1) Does anyone inscribe a rod's weight and if so, which method do you use and

2) Is the rods weight inscription and use somewhat irrelevant today based on stress curves, lightening, impregnation etc.  (Larry Tusoni)

I inscribe the rod's full weight as part of its description: taper, length, weight, my name and date.

I only use one type of hardware (Garrison style cap and ring over cork) so that is not relevant among my rods.  (Bill Lamberson)

I tend to agree with this info from the Jenkins Fly Rod site.

"Why don't you write the weight on your cane rods?

We feel that writing the weight of the rod on the rod isn't of a great deal of value - unless for some reason the owner wants to compare it to another rod that has the weight written on it.  It is true that the amount of cane in a rod tells much about its power and action, but only to a knowledgeable person.  So, the weight of the cane alone does mean something, but the number written on a rod is often its total weight, including ferrules, grip, reel seat, etc.  Since the weight of these components can vary (an aluminum cap and ring reel seat with a cork insert is lighter than an uplocking, nickel silver reel seat with a wood insert) the total weight of the rod doesn't say much about the actual weight of the cane itself. "

Wise words in my opinion.  (Adam Vigil)

I think the weight tells a lot about the rod, mostly for comparative purposes, but the distribution of the weight is ultimately far more important.

I think the location of the centre of gravity of the finished rod says more about the rod than the weight alone does. Ideally, for the required action, the rod should be as light as possible and the C of G should be as near to the hand as possible.

I think if the weight is indicated the C of G should be too.  (Stephen Dugmore)

But the center of gravity is going to vary greatly depending on the weight of the reel, line etc.  I don't think it's particularly relevant.  The feel of the rod/reel combination is relevant.  Most of my reels weigh more than the rods.    (Neil Savage)

I’ve found that the CG should be very nearly at the center of the grip and that’s a LOT dependent on the rod and reel combination as well as where the reel is mounted.  If the CG is under your hand during casting, even a heavy rod feels good.  I put a 3 ounce weight on my reel mounted to a PHY para 15 and it made a world of difference in casting comfort.  Beforehand the rod tip felt anchored to the stream bed.  Afterward it was a dream.  (Al Baldauski)

I guess it raises the question why write anything on the rod? The proof is in the pudding - test cast the rod and establish what line (and reel) feels best then go fishing - or just go fishing (I wish!)

Presumably if we write on the rod it is in order to provide a 'hands-off' description of the rod. In which case finished rod weight is a perfectly valid item to include in the description. But if it is included then I think the Center of Gravity must be too, for the simple reason that, all else being equal, a heavier rod may well feel lighter if the Center of Gravity is closer to the hand.

On the issue of reel weight, sure the reel makes a difference, but if we are interested in rod assessment (and design) we have to compare rods and if we are to do so we have to assume constants where possible - such as reel and line. Presumably no-one assessing two 7‘ 4 wt rods would test cast one with a Hardy Cascapedia and weight forward line and the other with a Sage Ultralight and a double taper and then compare them on that basis?  (Stephen Dugmore)

So where is the c of g? Is determined on a rod with or without a hundred or so different reels, lines, backing?  Does that also  include the 3’ of leader and a #2 weighted woolbugger hanging from the tip?  There ain't enough room on the rod for all that.  (Tom Kurtis)

Maybe that is why some are building the 13 strip rods.  (Scott Grady)

Sorry to harp on about this but I really don't see the difficulty in leaving the reel and line out of the equation initially so if you'll bear with me let's do that for a minute

The c of g is where the finished rod balances on a single finger.

If we accept that:

1.. 99% of rods have the c of g on the rod side of the hand

2.. the location of the c of g has a direct impact on how heavy the rod feels,

3.. the closer the c of g is to the hand the better in terms of how light the rod feels,

4.. a rod (and reel) should ideally not be any heavier than necessary (to perform the required action)

5.. no well designed flyfishing reel is going to tip the c of g onto the reel side of the hand unless it is itself unnecessarily heavy

then..

I think that all things being equal, no matter what reel or line you mount on the rod, the rod that has a c of g closer to the hand is the better rod, regardless of the weight of the rod.

I incidentally don't write the weight of the rod on the rod because on its own I don't think it is essential information and I don't think anyone intuitively understands what it means. I also don't write the C of G onto the rod because it is also not essential info (even if it is more useful). I do however design or tweak a design using the c of g.  (Stephen Dugmore)

Is it really possible, let alone desirable, to move the center of gravity to the handle without a reel and without adding unnecessary weight to the butt?  I have just been comparing c of g of a few of my rods, and without a reel, the rod with lowest (nearest the handle) c of g balances about 15" above the top of the handle.   It is a 7' 3"  #4 built as a one-piece.  It weighs 2.9 oz.  If the #13 ferrule was added (.15 oz for titanium or .23 oz for nickel silver) it would move the c of g up even further.  With Hardy Featherweight reel with line, it balances just above the center of the grip.  (Bill Lamberson)

My ideal is to keep both rod and reel as light as possible without compromising desired performance, so I wouldn't want to add any 'extra' weight at all. The idea is to move the c of g towards the grip by fine tuning and removing unnecessary weight not by adding it.

I would say your rod is well designed - it balances in the right place with a light reel. As the c of g gets further away the reel and/or reelseat would have to get heavier to balance the same way. On the other hand if it gets closer you could use a lighter reel or a grip that rides over the reel foot so that your hand can move further back.  (Stephen Dugmore)

My suspicion would be that true parabolic would not fare well using Steve's rules. Comments? (Doug Easton)

I believe Steve’s rules DO apply to a parabolic if you define CG as that balance point of the Rod AND Reel combination.  Even though a parabolic may have relatively more weight in the mid section, it is not “unnecessary” weight for a parabolic.  And while this “extra” weight in the mid tends to make the rod tip heavy, this necessitates a heavier real to balance it.  In an email of Friday I mentioned weighting a reel on a Para 15 to get the CG over the handle which made a huge difference in comfort despite the “excess” weight.  I do believe that, in general, a rod should be designed to be as light as possible, but a para will always feel heavier that say a straight taper of the same line weight IF balancing the CG is not accomplished. (Al Baldauski)

I don't want to to make a big deal out of it, but someone who wants to remain anonymous, sent me an e-mail couple days ago in which he said the following:

"Just checked an original PHY Perfectionist and its [CG is] between the stripper guide and first snake - one of the finest fly casting rods I have ever owned......."

Now I realize  that by design, a parabolic Rod is going to be tip heavy. I guess the question is are some parabolic rods better than others because they have CG that is closer to the grip? Or alternatively, are they better because they cast better? In my estimation, the proof of any theory is in practice.  (Doug Easton)

And I never said it didn’t cast well.  It SURELY does with enough line out to load it.  My OPINION is that it is “much more comfortable” to cast when the rod/reel combination is balanced at the hand.  The added weight to do so, while it sounds like a lot, doesn’t noticeably slow down the acceleration since it is located near the hand and it doesn’t cause casting fatigue the way the unbalanced rod did. (Al Baldauski)

Routinely, I write the rod weight on the butt. I report the weight of the rod full dressed immediately  before the varnish operations. Why? Well, for me it is a sort of homage to the tradition, just an indication for the owner without a real practical use. Considering that my rods with same length, same line, same dress, but different action, like progressive and tip action, have relevant different weight.  (Marco Giardina)

I suppose weight of the rod might be useful if every maker used the same construction method. I hollow build some of my rods. What will the weight or the weight distribution tell you about one of my hollow rods? Not much I  think.  (Jerry Drake)

I should know better than get involved with C of G discussions and actual physical weights of rods but I've noticed something interesting of late when I use a Driggs taper rod which I have been a lot of late.

When I want to cast for distance I tend to hold the handle deeply near the reel but for tight short casts I tend to creep up on the handle ie. farther up from the reel.

This isn't something I intentionally do it just seems to happen that way.

The only other rod taper I use much is a much heavier line weight as well as physically heavier Dickerson taper and I never tend to alter my hand position when casting this rod because anything other than the normal for me hand position is uncomfortable no matter what sort of cast I want to perform with it.

I mention this here because it's occurred to me that either the action of the rod or it's weight may have more to do with the kind of work the rod's doing that a single rule or thumb that can be slavishly applied to the C of G vis a vis.  (Tony Young)

Although a rod balanced at the hand feels good,  any weight(mass) added to achieve this balance will slow acceleration and reduce line speed. Marinaro suggested trying a cast without a reel (impractical of course) and with a heavy reel to exaggerate the difference. But this really is a game of aesthetics and I prefer my rods to balance in my hand, shotguns too.  (Harry Walters)

I don't mean to be pedantic but a couple of shells in the breach of a shotgun don't affect the balance of a shotgun as much as a reel on a fly rod does and is useless without one. None of this stuff matters one bit if the rod doesn't feel right when it's fished and if that takes a weighty reel so be it.

The argument of reduced acceleration that accompanies the introduction of added mass is also something I just don't get in the field. That implies there is the same amount of force applied no matter what the rod/reel combination which isn't the case of course.

When you fish a light rod you use less force, a heavier rod more. Yes, you'll use a few more ergs of energy with a heavier set up but you wont detrimentally affect the casting because in practice the caster adjusts to the balance or otherwise of the rod/reel and line. Any extra weight that may be required to the reel or whatever will be taken in stride. Assuming the rod taper is good and the caster understands the rod and the right balance of rod/reel is there and it's still not right perhaps the problem is with the line weight?

To return to the example I used in a previous post where I noticed that using a Driggs taper rod (parabolic) I've found that altering the position on the grip improves the feeling of balance depending on the length of cast. A short cast feels best with the hand farther from the reel than a long cast. That's altering the C of G constantly.This rod is reasonably light and I use a light reel on it.

Conversely a Dickerson 8015 I used for a time required a reasonably heavy reel to make it feel balanced to the hand. This rod would be virtually impossible to cast without a reel yet it gets a lot of line speed when you cast it with one which is of course the only way you would use it.

It takes a bit more energy to cast than the Driggs taper but then again the Driggs wont cast a whole line like the Dickerson does not for me anyhow.  (Tony Young)

Some of the old competition casters, in the English tradition at least, used drop the reel into their jacket pocket so as to reduce the inertia to be overcome in  the cast.  (Peter McKean)

I know but the fact still remains that if the rod feels top heavy use a heavy reel.  (Tony Young)

This thread got me thinking about a possible alternative way to express a rods center of gravity. What about listing the amount of weight at the real seat that is needed to balance the rod at the center of the grip? This would tell the buyer/user what weight reel would be needed to balance the rod if that was important to them.  (Will McMurrey)

The rod weight we feel is actually the acceleration due to gravity.  A static rod balances due to equal moments on either side of the balance point, but due to the rotational acceleration we apply to the rod when we start to cast the apparent CG moves away from this static position. Add the weight of the line which varies with the length of the cast, the aerodynamic drag of the fly and the variable rate of acceleration during each stroke and you can see that we can see that the balance point  (which we have been calling the CG) is rarely where we think it is.  (Harry Walters)

I have read all this with interest. Sounds reasonable, most of it. However, I think what most people forget is that the time a FFman spends casting is by far inferior to the time he spends following his fly on the water with his eyes, or his indicator, or just enjoying the scenery because no fish is showing; All that time he has a rod in his hand, and when the center of gravity is off balance, he will have to lift it to hold it more or less horizontal. When the CG is inside the grip, this effort is not needed. However small the effort is, after a couple of hours it will be a nuisance. A well balanced rod will not have this problem.   (Geert Poorteman)

Excellent point, Geert!

It is the rotational force on the wrist, generated by a C of G which is not in the hand, that becomes uncomfortable after a few hours of fishing.

WRT to casting, Harry is correct that the C of G must move about under different dynamics, but the direction of movement must be further up the rod than the static position and the rod therefore exerts more, not less, rotational force on the wrist when casting.

I therefore believe the argument for having the C of G as close to the grip as possible (rod action not being compromised) still stands, especially when you take Geert's point into consideration.  (Stephen Dugmore)

Some crude casting mechanics:

When you’re casting a rod, most people are accelerating it thru and arc with some straight back and forth motion.  In any case, the input force is a torque around the elbow joint which is located about 16  inches below the center of your grip.  So you can calculate the moments around your elbow contributed by various components of the casting system of say an 8 foot rod

1. 60 feet of 5 wt line (0.6 ounces) at 106 inches from your elbow.  Therefore: 0.6 X 106 = 64 oz-inches

2. 3 ounce rod blank with a CG about 42 inches from your elbow. 

               3 X 42     = 126 oz-inches

3. 6 ounces if reel, grip, and seat about 10 inches from your elbow.

               6 X 10     =  60 oz-inches

               Total  =  250 oz-inches

If you increased the reel weight by an ounce to balance up the system, the increase moment is only 10 oz-inches out of 250.  That’s not much.  It’s the equivalent of only another 10 feet of line out.  And if that extra weight to balance your rod/reel system made it more comfortable, you’d be out there casting it a lot longer!

250 oz-inches is the equivalent of a 1 ½ pound ball in your hand.  If you increased the weight of that ball by 1 ounce, do you think it would significantly affect the speed with which you could throw it? Well it’s only 4% difference.

The balance point in your hand is what makes it feel good.  The total of all the moments about your elbow is what determines how much force you have to apply to accelerate the system. (Al Baldauski)

How did our flyfishing forebears ever manage those 10 to 15 foot long rods made out of wood and later, even those 9 foot  three-piece GBGs? I guess we are just a bunch of degenerated wimps who have to have the CG of our 7 1/2 foot 4-weight rods just right or we will get too fatigued to even cast for an hour!

How do carpenters work all day with a 20-ounce hammer? Someone needs to talk to them about the CG and also get OSHA to revise some regulations.

If the rotation is at my elbow, do I have to add the weight of my forearm to determine the CG?

With everyone buying heavier reels, my lightweight Hardys and Orvis CFOs probably aren't worth much on today's market. (Garage sale?)  (Steve Weiss)

I think you're right basically. I think the fear of heavier bamboo rods though possibly not 10 footers is largely undeserved.

Just recently I had to nail about 10,000 roof nails. Started with a 20oz hammer and wound up with a 24oz. Heavier hammer but a hell of a lot easier to do the job overall.  (Tony Young)

It's a proven fact, that people today, are stronger, taller, and  better nourished, with more leisure time, than our forbearers.  What are we a bunch of pansy's, can't handle an extra ounce or two.  (Larry Downey)

Yeah,  I've  wondered  about  that too.   Can't  have a cane rod over 8'???  (Neil Savage)

They have a lot of advantages. Mend line better and handle bigger water easier as well as often allow you to get over reeds etc easier.  (Tony Young)

Yeah guys, I'm a 5 foot 8" 157 pound weakling.  One of my very favorite rods to fish is an 8'6" Granger Aristocrat 8642.  It fishes a nice short line off the tip and a good long line off the midsection.  It supposedly weighs 4 1/2 ounces, but I that's the blank only because when I put it on my scale, It comes up just over five.  At the end of about half an hour's fishing my wrist  gets a bit tired but soon after, things loosen up -- Then I'm ready to fish it all day.  It's certainly nice to be able to mend line and to follow your strike indicator without a bunch of line on the water.

I'm not sure that we  make rods in the 6 1/2 to 8 foot range only because were too weak to fish anything over 8 feet. Those who make rods to sell are trying to satisfy clients who are used to fishing inherently lighter plastic rods.  Interestingly the trend in plastic rods has been toward rods in the 8 1/2 to 9 1/2 foot range.

Of course collectors pay the big bucks for ther rarer short rods from the golden age.  (Doug Easton)

I have a rather delicate two piece  spliced 12' greenheart rod, made by John Enright of Castleconnell more than a hundred years ago, which I don't think anyone would find terribly heavy.

Long, heavy, powerful rods are needed for really large salmon water.  They used to fish rods all the way up up to 26' on the Ness, where extremely long casts were needed to reach the fish.

In Europe, Canada, and on the West  Coast these  days, two-handed rods are decidedly back in fashion.  If you are trying to fish big water, long casts are necessary, and if you are wading with obstacles behind you, you need to spey cast.  Today's large graphite rods are only somewhat lighter than the greenheart and split cane rods of the last century.  I've tried both, and I think that the wooden rods have much better action and casting properties. People who have practiced can get good distance with those carbon rods, but it's a lot more work.  (David Zincavage)