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How many ways do we have of describing/understanding rods?
How many of these are almost quantifiable? (Jerry Foster) I'd add two measures: 1. Percentage change in taper from station to station - easy to calculate and is remarkably similar to the shape of a stress curve for a similar rod. 2. Difference between a taper's dimensions and another taper you're familiar with. Bob Norwood's program uses a series of "straight-line-tapers" for comparison purposes. (Tom Bowden)
How many types of rod actions are there? ... Wet fly action.. etc.. can we name them? (Jerry Foster) I think you are screwing with us.............. But here is a start, Soft, Stiff, Quick, Slow, English wet fly, Parabolic, Semi Parabolic, Tip action, Mid action, Butt Action, Parametric. Any of the above can mean anything to anyone, at any time, and frequently does. Aghhhhhhhhh.......................... (Peter Jones) Add a few like, Medium, Progressive, Dry Fly, Full Flex, Nymphing, etc., etc. (Jim Bureau) And Hi Peter.. Heehee, no, I wasn't screwing with anyone this time... There are two obvious approaches from the responses so far. Those who use rod speed, (fast, med, slow) and those who use more descriptive language.. The thought was, some guy meets you in the store and sees your logo shirt and says, " Can you make me a streamer rod?". Of course you can, but does your mind bring up a particular shape, or do you have to run home and see what a streamer special looks like? There are probably n kinds of rods and they may all correspond to a particular kind of shape (stress). As we call ourselves rod makers, surely we can know that much about rod making. Maybe not. So maybe one at a time Dry fly action... what is a good picture (representation) of this kind of rod? (Jerry Foster) I will go along with you for a little with the "two obvious choices", rod speed, (fast, medium, slow), or "more descriptive language." The problem is how do you quantify by definition? This group for example has a tendency to want absolutes, and I don't know how to get there just with descriptions. Dry Fly Action, my mindset says this is going to be a quicker action rod, but the door will always be open to invite comparison. Three rods/tapers I have spent some time fishing dry flies with are the Garrison 109E, Paul Young Martha Marie. and a Dickerson 7613. The 7613 is a decidedly quicker action than the other two. All three rods fish dry flies the most, but are not opposed to a few soft hackles and the occasional muddler. All have very different rod actions, different pace in casting action.......... All dry fly rods? Descriptions by definitions from each of us are going to be subject to interpretation. We are all going to have to cast the same rod and check the boxes as to fast, medium, slow, and tally the results with which I am sure we will all agree with. This is not going to solve the "What action do you want" question from the rodmaker to the purchaser. I would want to put several rods in that person’s hands, and ask "Which do you like? Is this what you want?" and work from there. If he doesn’t have this option, but says "Just make me a PHY Perfectionist." Then there will be a lot more to define by all. (Peter Jones) Actually, the only actions I have heard of are: fast, moderate and slow and some in between. I can't think of what a wet fly action is! Most of my wet fly fishing is done with a 10 ft moderate action rod. (Grant Adkins) Pretty much what I was getting at, though you put it more succinctly. I think I know what 'fast' is, but if you've cast any of the newer plastic/graphite/carbon/boron/whatever-you-want-to call-ems, those can be incredibly fast, much quicker than I imagined possible even a decade ago. So what we call fast for bamboo has to be graded on a separate scale. I prefer the bamboo, naturally (no pun). Seems to me, you work less to get the fly out to a reasonable distance and everything from the leader to the fly to the fish appreciate a softer landing. Where it comes to 'slow,' well, if you ever seen my Uncle John, you'd know what that means! (Bob Brockett) The folks at F.E. Thomas listed six rod actions available from their company in at least four models: The Bangor Rod, Dirigo, Special, and Browntone Special. Not to mention the Streamer Special and possibly others. I'm trying to remember all of the actions but I can't right now. Three were listed under Dry Fly and three listed under Wet Fly. I'll have to go back to some reference materials. After casting a whole lot of FETs, my guess is that they did not have specific tapers for all six. I think they simply made rods, gave them a wiggle, and declared their action. (Reed Guice) I don't have too much experience with these things, but I thought there were only two rod actions: sweet and not to my taste (AKA crap). (Dan Zimmerlin) You know, Dan, I think you are pretty well right on the money here. There has been a little thread on shotgunning here in the last few days, and there is a great similarity. When I was a shotgunner, there were skeet guns, trap guns, trench guns, field guns and Lord knows what else. They had differing barrel lengths, stock lengths, comb settings and rib heights. But in the end the blokes who shot the good scores, the REALLY good scores were those who had the gun fitted by a competent fitter so that it was right for that shooter. When the gun came up to the shoulder, the master eye was looking down the rib at the correct angle and the gun moved well with the line of sight. I had a couple of beautifully fitted guns, a Beretta, a Winchester and a Stephen Grant, and I could shoot pretty well anything with them. With the Beretta especially. I have often shot 50/50 skeet with it, and best trap break with that gun was just under 300, and it was also my field gun for snipe and ducks. I think the same applies to rods - if you get a rod that suits you, that operates at your speed and in sympathy with your casting style, you will be able to use it for pretty well any type of fishing and/or casting. The actions available in this paradigm, then, are (1) those that suit me and (2) those that don't. How you design them, though, is beyond me. Up to now it has been a hit and miss thing. (Peter McKean) Another "vote" for "suits me or it doesn't": Coming back from the Colorado gathering and conclave, one of the things that struck me was how you can watch one guy cast a half-dozen rods, and just watching from a distance, not knowing what rods he's casting, you can sometimes say "There! That's the rod for him!" Of course, some guys at those meets can pick up any rod on the rack, club or wisp, and make it do whatever he wants, in a beautiful lack of effort. But many of us have a narrower range of strokes, and only certain rods really fit. For that "normal" guy that you're watching, some of the rods, his timing is off, too early or too late, and he throws a mix of tailing loops or open loops into the ground, and as soon as he puts some additional line out, problems magnify themselves. But then one rod clicks for him, the timing works, his loops tighten up, he drops tippets where he wants, and he gets another 10 or 15 feet out without thinking about it. The funny part is that if you talk with him, he may not have noticed that that one rod was the right fit for him. He'll talk about the nice finish of one of the other rods, or he'll talk about the rod upon which he read "Payne 98" (or whatever), or maybe he'll say "Yeah, I guess that one rod did feel pretty good...", as if it's news to him. I'm sure that many of us can grow into better casters, but I'm thinking that it's easier to get better if you start with a rod that fits your natural rhythm and stroke, get good with that, then expand your skills. Sometimes I wonder if part of our job as rodmakers isn't just sometimes to try to help those "normal" casters see what is right in front of them. (Lee Koch)
If the geometry of a rod makes a difference... To what do we attribute this?.. (could it just be a different taper?) with the exception of Robs none symmetric rods. Question...Thinking of rod speed...fast, med, slow... is there really a definition? (and I am aware each person has a different feel). As a starting point, think of holding two broomsticks in hand...one 7' and one 8', could we say they have a different speed? (Jerry Foster) They'll have a different speed if you spin them on a lathe and give them different speeds. Quicker tip tapers = faster rods. You can "slow' the whole apparatus down by lessening the diameter just ahead of the handle. Lots of ways to effect speed, lots of ways to kill it. (Bob Brockett) I don't think the descriptions of graphite rods match those of bamboo, for example, parabolic doesn't mean a single slow taper in bamboo. The codes only seem to me to complicate the issue. (Bill Lamberson) I am not familiar with those definitions by composite rod makers, but I agree with Bill in that your proposed codes have little utility for a cane rod. One of the nice things about cane rods is how much variability and variety we can build into our tapers without greatly changing where bend is concentrated. Most cane trout rods would probably fall somewhere between your class 1 and class 1/2 and yet could have very different characteristics in terms of what is called “speed.” I think Bill also makes a good point that slow and parabolic are not synonymous for cane. I find it difficult to believe they are for composite rods, but then I have not seen many composite rods being called parabolic today. (Tim Anderson) Highly recommend anybody really hung up on all of this get a copy of "Trout", both volumes ideally but Vol II specifically by Ernest Schwiebert and start reading at about page 57. After you read all Schweibert has to say on the subject citing Nat Uslan, Don Phillips, random Aviation and Naval engineers as well as personal opinions of himself, PHY, Dickerson etc you'll get a good idea of what when it all comes down to it is whatever the person casting the rod thinks the rod action is. He also has a good bit to say on different geometries and what you may expect by way of advantages and disadvantages of them in the pages before he leads onto actions. (Tony Young) For the purposes of this forum I would like to recommend that we first try to define what rod speed is and its importance in rod design. Giving a numbering system to system of rods (plastic) that could best be defined as fast, faster, fastest does not make sense for bamboo. Secondly I would like to point out (opinion) that words like parabolic and tip action have no relevance to rod speed. Any rod action can be made fast or slow. For-instance, we have one major faction of bamboo makers who like the terminology, "fast tip” ...in fact these rods when analyzed have fast butts and slow tips. But again this has little to do with overall rod speed. Any rod shape can be fast or slow. Defining the speed of various parts of rod may be important in design and FEEL but the rod is cast as a WHOLE, so the aggregate of all the parts define rod speed. (Jerry Foster) It seems to me, as previously mentioned I think, that looking at Schwiebert’s “Trout", book II, chapter six, “The Iconography the Split’Cane Rod” is to encounter about as good a philosophy/theology of the rods as has been ever written. Best would be to read the entire chapter that puts the reader in the mind of a superb analyst of the rods. There is a discussion of the tapers from P 965, but it seems so isolated just to read that. If you want numbers, there are plenty thereafter, but there is no attempt to classify the rods by number. Do we need it? (Sean McSharry) Rod speed is real..., tangible...What is it? (Jerry Foster) To me, rod speed is the amount of force needed to propel the line from fully laid out back cast to the forward stop without overpowering the tip. Using the right amount of force (arm speed) results in a decent cast. Too much or too little and the cast falls apart. For a rod that flexes down to the grip less force or arm speed is needed because the rod does a lot of the work so it is "slow". For a rod with a stout butt more force or arm speed is needed because the rod does less of the work so it is "fast". The tip also is involved because a soft tip is easier to overpower than a stiff one so a rod with a soft tip will be slower than one with a stiff tip. The line used is also involved. Over lining makes the rod slower and under lining makes it faster. It is a combination of all these factors which determines the rod's "speed." Anyway, that is what I think it is. What do you think rod speed is Jerry? (JW Healy) Great response... I believe you have captured the essence of how we feel, adapt to rod speed. And indeed, the application of force is probably how we judge speed. The problem we have is how do we quantify that force? The mechanisms would be impractical for most rodmakers and still don't resolve the issue for caster to caster. That's why I tried to use the standard of two rods in hand at the same time. You can set your own values. And I am trying to consider a predictive value and not post glued up rod value. (Jerry Foster) I am a biologist by training, a veterinarian, and not an engineer or a physicist, and very wary of getting into the "definition" thing! It seems to me that speed is a function of the time taken for a rod to pass through a neutral axis, or resting position, following displacementj from that axis. Which, if not the most useless piece of information for a working rodbuilder I have ever heard, is at least a lot more useless than whatever is in second place! What I want to do is make a rod that suits the purchaser, and does what he wants it to do. If he wants a fast rod, then I want to build him a rod that, at least, HE thinks is fast. Most of the buyers are one-time buyers, and really, they want their new bamboo rods to feel pretty much like the graphite rods they have been fishing all their lives. So while I, in between plating tibias and neutering German Shepherds, may like to cogitate on the mathematical underpinning of what I spend so much time doing, in order to have a predictive facility to offer potential buyers I have gone back to non-technology. I just keep giving them rods to try until we find one they like a lot. The old bespoke London gunmakers used "try-guns" to determine fit, and I think the concept of the try rod is quick and practical, too. If they want a fast rod, I keep handing them rods (sometimes the same rod more than one time, at that) until they find one that they feel is "fast", and that they like. I often send the rod away for them to play with at home and to fish, until they are pretty sure it is what they want. It's nice to feel academically justified, I guess, but basically I want to build a rod that the buyer likes, and continues to like. Interestingly, even if their tastes change and they end up with rods in the stable which are more classically "bamboo" in action, they nearly always continue to love the first rod (which is, more often than not, a derivative of the Payne 98 with a beefed-up butt section. " The Cannon," a guide friend of mine calls it). (Peter McKean) Ironic, isn't it? Half a century ago when fibreglass rods appeared on the market many were advertised as having "bamboo" action. Now we're trying to build bamboo rods with "graphite" action. Hmmm. (Ron Grantham) Cantankerous beasties, are we not! But really, in my position, and I imagine I am far from alone, I build rods because I like them and I enjoy the job of building them; surgery is not a very precise business - if you put two bits of a cat in he same ROOM, they're going to heal. It is nice to do work where I DO have to be reasonably precise. And not to have to worry about blood! I am not a real professional. I have built getting on for 150 - 200 rods all up. I can easily sell more than I can, or want to, build. With the result that I tend mainly to build rods, whether I sell them or give them away to friends or fundraisers, for people that I know and like. If somebody rubs me up the wrong way, I just will not agree to make him a rod. So, in this scenario, of course I want to build rods that the owners will be happy with, and will want to fish; and that will stand up to a fairly big workload in a lot of cases. So I am very grateful for the designers and the thinkers for what they do for me and for the craft; I do occasionally build a rod to a design that seems to me to be very avant garde, but to be honest I am a poor enough caster that they are beyond me by the length of the home straight. And I can tell you that I would have b....r-all chance of selling one to someone who really wants a brown hexagonal version of his favourite graphite. It may be worth noting that, after 49 years of it, I am a competent veterinarian - but I don't develop new surgical procedures nor diagnostic techniques. I just use what has been handed on to me by the ground-breakers, bless their little hearts! (Peter McKean) Shapes, (character) progressive, linear, parabolic. are just that, named shapes of certain contours and are independent of rod speed. Not everyone uses pure linear rates of change between stations (slope) to define their rods. it is true that slope (the taper) does define rod speed... But as I previously stated the rod does not actually cast in sections. When a force is applied to a rod the force is applied to the entire rod, simultaneously. The energy of the force is absorbed, transferred, dependent on the mass of the bamboo at each moment, the taper. As to how each of feel speed, I agree, it is individual, but I believe within good casters there would be a general agreement about whether a rod is fast or not. (Jerry Foster) OK... Here's the pointI don't believe that it is impossible to build a family of rods. A 7' 4 wt. and an 8' 6 wt that, other than static weight, feel the same when cast. Not just similar, but the same. You have all cast and made a lot of rods. So it should come as no surprise that the like-ability of a flyrod comes down to two major components: The Shape of the Taper Most all have used A Garrison stress curve program (or one of it's derivatives) to evolve/modify or define a taper. The Stress curve model very clearly shows the shape (character) of the rod. Whether you think it is accurate or not it is a constant that has a predictable outcome. We can use this program to change the basics (length, line wt) of any existing taper and be reasonably assured that the resultant rod will be very similar to the original. So the character aspect of the equation has been adequately accounted for. The problem is that any modification of this type (wt or length) does not account for the resultant change of speed. If you shorten an existing rod it becomes faster, and the corollary. In my wanderings I had found NO definition or Rod Speed. Just words... And we are left with no accurate way to programmatically (mathematically) solve the problem. Mainly guesswork based on the slope. Thus my quest...and my incoherent questions. The cast. We have a stick with a taper, we are going to apply a force to it, it has a resistant load of a length of line. I am going to fling it out there somewhere. It takes a certain amount to time to do that. Milliseconds. Immeasurable and irrelevant if measured. The force causes the rod to move and load (stress) the rod and results in the rod bending (deflecting) up to the stop point. Then the rod unfurls (springs) and flings the line out there somewhere. So What. What do we know...we know that our hand has felt the pressure of the resistive load (feedback), and the micro-timers in our brain have registered a timing interval? Without the latter we could never cast graphite because we don't get much of the former. How well we do this as individuals is defined by our athleticism. Doesn't mean much but it is my contention that, that is what we are using to register ROD SPEED. The time it takes to go from Stop to Stop, or maybe stop to loop stop to loop. (maybe Robin even concurs). Back to my Broomsticks. I don't think that you can argue with the fact that the two broom handles would have the same speed. The longer would have more line speed but the rod angles (a line drawn from the tip to the butt at the stop point, the point of maximum deflection) would be the same. Straight down the rod in this case. Currently Larry and Max have commercially available programs that show this angle...although I understand that Larry's doesn't define that angle yet. The point is, I can know that angle. Hypothesis: ANY ROD AT MAXIMUM DEFLECTION THAT DEFLECTS TO THE SAME ROD ANGLE WILL HAVE THE SAME ROD SPEED. Arguments now. (Jerry Foster) What you say makes sense Jerry. Just one thing.... you say " Then the rod unfurls (springs) and flings the line out there somewhere". I think technically this is a very small part of the process of getting line out. A rod is primarily a lever, not a spring. Hence one can cast with a broomstick or with one's hands - a full line even. I think the bending of a rod is primarily to assist in keeping the tip following a straight line - and thus keeping a tighter loop and greater line speed - with minimal need for making this correction by moving the hand position relative to the body (as one would have to do when casting with a broomstick). I think the speed of a rod is the angle of the arc it travels through from stop to stop- which defines a time period. Smaller arc = shorter time = faster rod. The angle of the arc is in turn defined, as you say, by the angle of deflection at maximum deflection for a given length of line. The arc that the rod travels through is defined by the path of the tip. Which should follow a straight line. So the 'stop' points are defined by the points at which the tip would start to dip below the straight line unless the position of the hand is moved to compensate for this or the cast is stopped. With regard to the broomsticks assuming the same arc, time period and hand position the longer broomstick would generate more linespeed through the faster speed of the tip but this may well be offset by the larger loop size which would slow down the linespeed. Certainly it would in practice be much easier to generate faster linespeed with a shorter broomstick. The shorter the better in fact. In my experience faster rods typically have tighter i.e smaller radii of bending in the tips and larger radii in the butts. i.e relatively thicker butts and finer tips. (Stephen Dugmore) The reason the spring is in play is because the rod tip is still 2' +- from forming the loop. Therefor the spring must continue to accelerate the line till the rod straight position... I don't think it has any effect on rod speed however. A rod that has bent a lot will have a lot of unbending to do. Which just continues (in this case) the slow paradigm. (Jerry Foster) A further thought... The speed of a rod could equally (possibly) be defined by the distance the tip lies at maximum deflection from where the tip lies at zero deflection (i.e. after recoil) (Stephen Dugmore) I would like to point out that there is one variable. The line out, or line to fish... The rod must be loaded with length of line appropriate to the fishing distance for that weight of line... especially when changing line wts for a new rod. (Jerry Foster) Actually it couldn't be 'equally' unless the rod length is defined. The angle of deflection is a better measure. (Stephen Dugmore) Again, why is rod speed so important. You have all of your demo rods laid out and the guy says I love this rod (7' #5) but I need a longer 4 wt. So you manipulate the taper using stress only to discover that the rod is similar but not the same... The problem is when you stretch the rod out it becomes slower. If you manipulate the slope to make the rod faster, you also change the plane of the stress and indeed have a truly new rod. But it is not the one you set out to build. However, If you know the rod angle of the original you can bring the entire stress line down on the new rod until you match the rod angle of the original without distorting the original slope. I know some of you have questions or challenges... Please post them (Jerry Foster) Jerry, with each of your posts I grasp a little more of what you are seeking. Jerry's goal is an important one, I think. If we can quantify rod speed with some degree of confidence, the math to adjust tapers to new rods is possible. The Bokstrom taper slope measure that RodDNA calculates should be related to speed somehow: the greater the slope of the taper the faster the rod, other things being equal. I'm not super comfortable with choosing two arbitrary points to characterize the rod though. The default is the 10% and 60% points as measured from the tip; but surely what is going on in the rod butt from 60% on is critical to the speed. And the Bokstrom measure doesn't account for ferrules. If you take the same taper and add more metal ferrules I think we agree it will slow the rod. The stress curve seems to tell us something about rod speed as well. High in the middle and low in the butt means a fast rod, and vice versa. Stress numbers also account for weight, like ferrules and hollow building. But the curve itself is often so higgledy piggledy (technical math term) that judging something from two arbitrary points is dumb. You need to look at chunks of the stress curve. It also seems to me that the tip region (top 10-15 inches) while critical to the cast is not where the rod speed is determined. Based on this line of thinking, I've added a calculation to Hexrod, just for discussion purposes, that computes a rod speed index. It has two components: a ratio based on the stress curve and an adjustment for rod length. Here is how it works:
You can try this out on on the Hexrod website for some rods you know and see if it jives with your judgment. (I'll be amazed if more than 2 people agree on anything.) (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) I'm getting the basics of what you suggest Frank (though I must admit I am largely procrastinating because I don't feel like wrapping this rod today). I like the ideas but think the implementation may need a little refinement over time. Most rods have a high point for stresses somewhere between 10-20 inches. I have always felt like any part of the rod above that stress high point largely folds out of the way as we cast. (Jerry has done quite a little work with this idea.) Perhaps rather than skipping a standardized 15% at the top you could ask the program to move to the high stress point, wherever that is. Should be close to the same area. I compared a handful of 7 foot, 7.5 foot, and 8 foot rods with which I am familiar. Your ratios seem to me to make the 7.5 footers a little faster than what I would have expected. That may be simply my perspective. I hope others will weigh in. (Harry Boyd I read Frank's post and understand that he would like to modify his program to simulate deflection rod angles...That would be great for everyone. But that puts everyone the cusp of another problem. I will offer this up as a starting point… I will call it "Max's Law" because thats where it originated. It is a way to break rod angles down to speed ranges. -15 Very Fast (telephone pole stiff) The numbers are degrees of deflection (bend). NEXT... and most important Everyone on the list can contribute to this if you fish. It would be nice if we could accumulate a set of semi-standard values for line out or line to fish for the various line weights. HOW MUCH LINE DO YOU TYPICALLY CAST WITH ALL THE DIFFERENT LINE WEIGHTS. YOU USE. EVERYONE. I understand that most fish or caught within 30' so you can skip that... We are looking for the rods sweet spot with a given line wt. THE PROBLEM: I recognize that most of the software programs use 30 and 40 ft as a default for all of the line weights. That is fine if you are using and existing set of numbers (known rod) and just comparing stress values. BUT... when you change line wt. or rod length this value now defines the load for the original rod and therefor the derived new taper numbers. This is lot different than showing differing stress values at different "to cast" distances. It actually defines the rod angle of the old/new rod, so it has to be reasonably accurate. If you are using rod angle to adjust for speed the original rod must be stressed with the appropriate load. (Jerry Foster) I think 'deflection angle' (defined as "A LINE DRAWN FROM THE EXTREME BUTT TO THE EXTREME TIP") is an interesting and arguably important factor in determining the character of a rod. However, I don't think it is an accurate way to define 'speed', at least as the term exists in the common vernacular. As a general rule it might work OK but as you for many tapers (parabolics - of which I know you love that term - are a good example) I'm not sure it holds up as well. Of course, if you want to define 'speed' to equal 'deflection angle' than that is fine, but what you are not doing is pinning down the commonly used meaning of 'speed', rather you are changing, or perhaps limiting, its meaning. I put together a web page a while back that shows the deflection of various common rods (or for those that are not 'common', rods that are indicative of a 'type' of taper or have some other specific trait that is worth comparing) at the point of highest stress/bend during the casting stroke. I also only included rods that I have personally built and cast so that I could have a decent grasp of their real life casting action. All of the rod deflection simulations were made using DynaRod and are all 8' 5 weight two piece rods with 50' of line cast. At the bottom of the page are Garrison stress curve charts including the rod taper numbers used, most of which are in Hexrod and/or RodDNA (the straight taper Powell B8.7 is an exception but is easily computed using the Powell B formula). For many of the rods the 'speed' and 'deflection angle' correlate just fine; the Dickerson 8013 (1949) is commonly considered 'fast'. According to the deflection angle the parabolics, on the other hand, would be considered much faster than any of the others and, please correct me if I'm wrong, very few people would consider these rods to be anywhere near 'fast' action. The Winston 8052 is another that is interesting as I would consider it one of the slower feeling rods (parabolics aside) but using the 'deflection angle' definition for 'speed' it is faster than several of the rods that I would in real life casting consider faster - the Dickerson 8013 (1951) is a good example. Using the definition of 'deflection angle' above, if you turn off all the curves except for the Clark Gierach/Best, the Payne 102 and the Powell b8.7, you can see that all three of these rods would have very near identical 'speeds'. However, if you put these three rods into most caster's hands, they would say the Clark is the fastest, and even if all casters didn't agree, I would wager none would call them all the same 'speed'. So again, if we're trying to find a definition for that ephemeral yet commonly used word 'speed', the 'deflection angle' is, at least in my opinion, only a part of that definition. I think Frank's suggestion would be extremely interesting to experiment with. It potentially takes into account more of the character of the rod, that is, where along its length a rod bends, as well as the [adjusted] deflection angle. I'll try to mess around with it some as I can get time this week.Like Frank mentioned, I've always found that a trend line through a Garrison stress curve or a DynaRod action genome is a decent way to get a general feel for a rod's action. Of course, that is both anecdotal and somewhat inaccurate, as you clearly mentioned Jerry, given the wild nature and extremes of many of the stress curves out there, especially those whose tapers are measured from existing rods. (Chris Carlin) I consider rod speed as how fast I can put it together and feed my line through the guides so I can beat that guy parked beside me to river so I can get a better spot than him. 4 piece rods are always a lot slower.... (Ken Paterson) One comment on slope adjustments. Most of the rods we make are compound in nature. they have various meanderings through their length (some planned some unplanned). Unless you build pure linear rods.When you use slope to adjust the rod speed the you cannot help but skew the relationships of those high and low points. This does not make it a bad method; in fact it works well. but it does NOT accurately duplicate a rod if you are trying to make its big ugly twin. (Jerry Foster) And I had a typo in a previous post... the numbers should read: -15 very fast Would it be possible to export the experimental Rod Speed number(s) for all the tapers at once? Perhaps in a delimited or Excel format so they could be more easily compared to each other? (Chris Carlin) Here is a link to a spreadsheet with the speed index number for all the rods in the old Rodmakers taper list. Those who are interested can see if the index jives with their judgement of rod speeds. And here is my take on where we are in this discussion:
I'm going to have to leave this topic alone for a week or so. I'm a couple weeks behind in stuff I promised to paying clients. If they don't publish they perish, and I don't get paid. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) This information puts 2 of my Bamboo rods in the class of 10 to 25 Medium Fast and 2 rods at 25 to 30 Fast. I also have a St. Croix that is Very Slow - Noodle and worthless. (Lew Boyko) Yes I could get the speed index for the rods in the Rodmakers listserv taper archive. I have the stress numbers alreadycalculated. Jerry's point about line weight & length is very important here. Most of the trout-size rods in the Rodmakers archive I set up with 30ft of DT line cast. That was a long time ago (15 years?!) If I were doing it today, I'd use 40 feet. Anyway, stress numbers depend on the line weight and my experimental index depends on the stresses. So if you are comparing rods, or designing a new one based on an old one, you have to be careful to get the line weight & length right. Whether there is a consensus standard, I don't know. And also, the line weights Hexrod is using now (prepared by Chris Carlin from the Cortland website) are more detailed than what I used back then. For the Dickerson 8013 in the archives, with 30 ft of DT5 line cast, the A/C ratio is 1.37. Go to 40ft of line cast and the stress values in the A region go up more than the C region, elevating the A/C ratio to 1.51. I've got some good ideas from people on directions to explore. I'll work on them as time permits, and ask for help when I get stuck. It may all turn out to be a blind alley. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) What a thoughtful response. First, about Para's. I had to tussle with that myself. My conclusion was, the numbers don't lie, so why do I think they or slow? I have tried to point out that there are 2 factors involved in the feel. Speed---Shape. In the case of the para's my conclusion the feel of the shape overwhelmed the sense of speed. And the casting stroke is modified so there is a pause between direction changes which makes us think slowness. There is no doubt in my mind that para and 8013-49 (the closest you have listed) take almost the same amount of time to deflect. The speed I am talking about is the rod itself, as designed, not just limiting it feel or sales verbiage. No inference. But rods on the market get called a lot of things. Secondly, if you want to modify a Para, wt, length, the rod deflection angle works. That is if you want the same feeling rod. My point has always been that speed alone is not a good way of classifying rods. I am only trying to pin speed down enough to allow us to make rod families. And you are doing what I and most others do which is conflating character and speed. They coexist in the rod and one may be more dominate to the feel, (in any given rod) than the other. There is little doubt that we feel the way the rods are bending. Speed is just an impression. And overall, my intent is to propose a method of predictably modifying rods. If you don't like speed, we can call it the x factor. The other unmentionable here is that speed is a function of force. We tend to modify it when casting from rod to rod. But as a function, the 4g standard serves as a good enough constant. It may well be that after one stroke with and unknown rod we recognize para and change to 3g's. But that is irrelevant to programatic modification. I am trying to take the human out of the equation for this purpose. How many times have people told you a rod is slow and you KNOW it is fast? (Jerry Foster) I have been making rod "families" for about 5 yrs in that, if I come up with a design I think I will like I make a 5 wt and if I do like it I will make a 3 wt or a 7 wt or both using Larry Tusoni's Designer program to calculate the dimension changes. When this discussion started I went back and looked at the charts and I am not quite sure how to interpret them. In all cases the stress curves for the different weights and lengths of a given family were the same. The deflection curves, which I hadn't paid much attention to until now, consistently showed the lighter weight rods had a greater deflection than the heavier weight ones and the shorter length rods (7'6" vs. 8'0") had a greater deflection than the longer ones which I think means that the lighter, shorter rods are slower than the heavier, longer ones. Some of the rods have exactly the same beginning and ending points on the deflection curve but are different in the middle so the angle from tip to butt is the same but the total curve is different. I am not sure how to interpret this. However, if I use the same casting stroke when casting these rods, while the "feel" is different, I get proportionately similar results (7wt throws father than 5wt and 5wt farther than 3wt but the differences seem to be proportionate to the line weights). So I am wondering if we are not seeing differences without any meaningful distinction. If the caster is happy with the 5wt won't he/she will also be happy with the 3wt and the 7wt? (JW Healy) I think I get where you are going. Sorry, got my 'hows' mixed up in the paragraph below. Here is 'how' it should read: Ah, I see, word definitions. Deflection and Stiffness looking at one side, or the other. Maybe a term like "Imbedded rod speed” would be a better fit. This gives us a way to see the rod speed part of the stress curve. It all goes back to. Put two rods in your hand, make a cast, each with appropriate line load. At the theoretical stop, both tips line touch the same max deflection line. Why aren't they the same speed? Maybe they are, but they don't feel the same. I think I just explained it to my self again... Your argument is based on different rods. I have been arguing for a long time that the Character (Shape) of the curve is as of much importance as the speed. So, your argument is based on the real world of "perceived rod speed" which is the combination of the two. So if we contain our discussion to my real point, a big brother rod. The same taper, modified, retrofitted to the same rod angle, does it make more sense? And JW, these changes are subtle, I'm looking for brothers or sisters not what I would call cousins. (Jerry Foster) You folks have me all confused by trying to change the language of beam deflection that has been in use since the mid 1700s. None of what you are saying correlates well with the Euler-Bernoulli or the Timoshenko beam theory. The line drawn between two points on a graph of the function(x) that represents the taper of the rod is called a secant line and is the average slope of that function. The same can be said of the function(x) that represents the deflected rod and represents average slope of deflection of that deflected rod. I for one would like to see the language of rod design be a little closer to the language of classical engineering and physics rather than some new made up terms. OK, I am done here, continue. (Jerry Drake) That's nice...And yup... Bosons also...so much I don't know. It would be helpful if you would explain how a secant would solve an issue with flyrods that has never been resolved before, since the 1700s anyway. Averages are an anathema to Fly rods, unless we are speaking in generalities here. Hehee (Jerry Foster) How about we look at rod "speed" as a measure of the fundamental vibration of the rod and state it as the period of vibration in seconds? (Jerry Drake) There was an article published in the American Journal of Physics, volume 58, pp 234-240, 1990 by John M. Robson, "The physics of fly casting". He considers the rod as a simple harmonic oscillator whose mass load and frequency includes the line until it decouples and is launched into the cast, where upon it reverts to just that of the rod. He gets some decent results comparing his calculations of the shape of the loop to high speed video of fly casts. His model of a rod was fairly rudimentary, but it at least considers a bend in the rod. The math level of the article I would say is that of advanced engineering/physics undergraduates. That's nice Mike. Did Mr. Robson resolve our issue? (Jerry Foster) It's much more of a step in the right direction than forlorn hopes that various slopes, angles, ratios of stresses will some how be a magic bullet that characterizes the timing of events in the casting stroke. The oscillation frequencies are direct measures of this timing. The extension needed for the article is a consideration of real rod tapers rather than the simple model. The validation would be the comparison of the calculated cast loops produced to that of a rod with the taper in question. (Mike McGuire) The whole thing about pinning down rod action is, I think, at the risk of sounding all touchy feely is all a bit like music. The Garrison or Robson models or whatever else comes along are describing the notes, very good at pinning down discrete sections of the rod, not that difficult to pin down and describe but the music is really in the cords and these work with the notes. Cords are almost unlimited in their scope and only mean something when listened to overall. Some hit the sweet spot and make the notes work better, others don't. (Tony Young) Didn't John Long measure oscillations in the Grand Experiment? (Bill Lamberson) Dangerous territory here, with so many people so much more qualified than myself, but a thought that has not been discussed for a while is how we adjust our casts with different rods. With a fast graphite rod, my hand and arm doesn't move much to cast, and hence all the beam theories come into play. With a softer bamboo rod, I move my arm back with the line, load the rod with a longer forward movement then once loaded, allow arm and wrist to determine the loop I want in the forward cast. So beam theories don't work completely as my fulcrum is moving. A fast rod takes less arm movement along the casting direction, while a slower rod uses more arm movement to load and deliver. So not just angle and arc, but also length of arm movement in the cast. When I watched those old videos of Lefty Kreh and 12-year-old kids casting a full lineon the lawn, it was about getting the rod loaded, not fulcrums that delivered the cast. So in summary, I'd suggest some measure of the angle as well as the distance the arm travels to load the rod as starting points in determining fast or slow actions, as indeed we casters (poor or good) do adjust to make our various rods work. Thanks for the discussion and thoughts. (Tom Park) Doesn't matter if your fulcrum moves - it's still beam theory, and statics and strengths of materials. A beam, is a beam, is a beam. All moving the fulcrum does is move the stresses around a bit. (Mark Wendt) A welcome respite. In summary: There are two major factors at play here, (plus he entire universe of imponderables, quantum vibrations and all) Humans, Rods. The person holding the rod is the final arbiter of Speed. I didn't intend to step on anyones sensibilities by using the term "perceived speed", I was simply trying separate the rod from the person. As Tom pointed out, and as we have discussed through the years the are a myriad of ways of defining the casting stroke and the feedback loop. For my intended purpose it doesn't matter. Take any one of us, the thing we all do is start the cast and end the cast (stop to stop). This motion gives you an impression of the rod (shape, speed), For these purposes I hope it made a good impression because I want to make you another rod 7 in longer with a different line wt., BUT I don'f care how you came to your decision. The mixture of speed and shape were to your liking. So this isn't about new design, or how you make a rod, or how a rod should be made. This was about, after dozens of attempts at making a family of rods why doesn't this new rod feel the same as the original. I also know that no two rods will ever be the same. But I should be able to get closer than, it feels kind of similar to that other rod. I'm not looking for identical here just closer. We all, including myself, understand that in making a rod longer or heavier it will not feel the same in hand. The objective is to make you say, after casting it, it gives me the same feeling as the other rod. Separate from what what the caster is doing the rod is doing what it does. It is stressing and bending and unbending. A little aside here. these are not original thoughts but are based on insights after using Dynarod program for about 10 years (and I know I'm slow). What did it do? It showed me that there was this rod angle. The angle from the butt to the tip at the stop, max deflection. It doesn't matter how quick, how long, how powerful, each us will reach that point in the cast, the rod will be at max def at the stop.And whether the scientists out there like it or not, it represents a time frame. It doesn't need to be measured, and it doesn't matter what it is. It is each of our strokes, individually, from stop to stop. It doesn't matter what the shape of the rod is, if any rod at max def lies on the same deflection angle, given the same stroke, it took the identical amount of time to get there. In this case we are discussing rods with the same shape. Is it dispositive, you decide? (Jerry Foster) EXACTLY! (Peter McKean) In fact, as I am always scratching for something to use as a model name for rods, I build an 8-footer of my own design - oops, sorry, my own empirical blundering about - which I think I will call the "Timoshenko Triumph!" Quite appropriate, as I must admit a slight tendency for the rod to twist a little bit under load, due, doubtless, to a perceived lack of .0001 accuracies in form setting and planing! It is a delightful rod with which to fish, nevertheless, though the taper demands more technical skill in the casting stroke than I am able to bring to bear in order to realise its distance-casting ability. We have a local casting guru, Peter Hayes, who is almost in the Rajeff category, and it is a delight to watch him cast the thing. :-) (Peter ( if-he-had-another-brain-it-would-be-lonely ) McKean) That's your mistake right there! Had it been the Euler-Bernoulli Behemoth it would have been stiffer, if that's what you wanted. A rod is not as well suited to Timoshenko since it's best used for short sections. Also not that sure it's really a beam. (Tony Young) Aha! But not RESTRICTED to short sections, and very appropriate in that it acknowledges twisting as a possible occurrence. However, my Applied Math II is just not up to showing me the short beam/long beam bias in the expressions. You are doing a good Wikipaedia quote there, though, Tony! Very thorough research work, as Tom Lehrer would say.... I would not consider Euler - Bernouilli because the first part of the name may lead people to think that I may "oil" my rods, and because Bernouilli is more inexorably fixed in my mind as associated with bloody haemodynamics and venturi effects, and many painful hours of slog work in my University days. So the choice was not a serious one, but purely a light-hearted jibe. (Peter McKean) Nope, it's the basic difference in beam theory. Aaron's was deeper into it more then I, he for Naval Architecture, me for civil engineering though I must say it was a very big target too good to pass up. Smart lad is my son. (Tony Young) That was a very strange reply. Comes of editing and not looking at the big picture. Sort of like hoping that study of discrete points of a rod themselves make for a good rod.
Now while Timoshenko beam theory is not restricted to short sections the action it describes is not something to be desired in a fishing rod and should prob be designed out of it which is why I prefer the idea of the Euler-Bernoulli Behemoth but that's just me. You don't have to have been to school back in pre WWII days to have been taught things. They're still teaching it today. (Tony Young) Tony, it was a joke! It was not any of it serious! It was a shot at pretentiousness. I said very clearly yesterday that I am not a designer. I am a builder and very occasionally, a modifier. I drew the analogy that I am competent also at my profession but am not a developer of new techniques of either diagnosis or treatment - I just depend on the researchers for all that, and I am filled with admiration for their work. There are truly few Renaissance men extant, and I am certainly not one. However, I think I am moderately able to tell significant work from mumbo jumbo. I have been doing it for a long time. And it is a characteristic of these "rod design" sessions that not only are they largely mumbo jumbo - but also that the couple of people who speak in favour of keeping in touch with accepted scientific method tend to get put down quite severely. I said that the part of the prodigous Bernouilli output that relates to haemodynamics caused me a lot of angst in my student days, to the extent that I have a tendency to think of him only in relation to fluid mechanics. I made no comment on what they teach these days, though I DO employ some of the graduates, or used to. Here is a comment, though, that is both serious and considered - in my student days, we could get in to University pretty easily. To make up the leeway, they did teach the hell out of us because we were not all that clever academically. If you had two of most things you were supposed to have two of, you were in! These days, matriculants need to be geniuses to get in. They are academically miles ahead of what we were, and able to cope with floods of information that would have made our minds boggle. This has resulted in a style of teaching very different from the one we experienced. Worse, perhaps? Who knows? Just different. Certainly, the changes, along with the fact that most courses have been shortened, have meant that room has had to be found for all the extra stuff; and that room has come largely at the cost of reduced basic academic underpinning, which is NOT a good thing! HERE ENDETH THE SERIOUS BIT. Apart from that, it was a light hearted sally, spearheaded with barbs equipped only to pierce the thinnest of skin. (Peter McKean)
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