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I'm getting ready to makes rods 3 and 4 and in the process of selecting a taper I recently had a nice online conversation with Larry Blan in which I looked at Hexrod for the first time and "sort of" used it to adjust a taper. I was hoping that maybe I could start a little hypothetical conversation about how to use Hexrod to adjust tapers. I really enjoyed reading all of the recent taper discussion, but to be honest it was way over my head in terms of understanding bamboo. So I was hoping that all of you who have lots of experience could help me (and probably other new makers) become more familiar with Hexrod. Here's what I think I understand. If I have a taper I like and would like to make a rod that has the same type of action but is either a different length, casts a different line weight, or is a different number of pieces then I should strive to change the dimensions of the rod while keeping the stress curve the same. Right? I also think Hexrod will help me do so. Right? Is it as simple as calling the rod up and changing the fundamentals of the rod while holding the stresses the same? That seems too easy. What else is involved? Here's what I'd like to work on. A hypothetical example. Take the taper for the Driggs River listed in the archives (the one Wayne posted). Right now it's listed as a 7'2" 4 wt 2 piece. What if I wanted to... Change it into a 3 piece (I know it's already been done and posted, but I'd like to investigate the process myself) Or, change it into an 8' rod. Or, change it into a 6 wt. Am I right in thinking that all of the above could be done to create new rods that have the same characteristics (casting action/feel) as the original? I'd like to keep the discussion to changing an existing taper not creating my own (I'm no where near that point in rod knowledge). (Aaron Gaffney) Sounds to me as though you have a pretty good idea on how Hexrod works. In its most basic sense all you do is plug in the numbers as you describe, hold stresses constant, and voila -- new rod. Only when I want to change the action of the rod do I find myself doing much more than that. I am a little more careful when making big changes. To use an absurd example, I would not think that Bob Nunley's 6' 2 weight could just be bumped up to a 9 weight with no further adjustments. But why would anyone create a 6' 9 weight??? Making big jumps usually requires a little more thought. You really do not want a 9' rod to cast with the same action as a 6' rod. That's not in any way a problem with Hexrod. It's more a rod-design consideration. Here are a few of my own thoughts on rod modification. They are just my opinions and assumptions. These are not written in stone, and I really hope others will challenge some of these thoughts: 1. Parabolic tapers like the Driggs, Para 15, and others work best as two piece tapers. Since the rods bend most at the 1/3 and 2/3 point from the tips, in three piece versions the ferrules (which create stiff points) are in the worst possible places. To adjust a two piece parabolic taper to a three piece may require more fiddling around with the taper to make it behave similarly. As a disclaimer, let me add that I'm a former para-hater. Though I'm coming to like them more and more (or dislike them less and less, depending on one's point of view), I do not have tremendous experience with parabolic tapers. I did build a three piece version of a Para 14 as my first rod, and have never really gotten the hang of casting that rod. It just feels soft and mushy to me. 2. Increasing or decreasing rod length a foot or more forces you to think about how the original length figures into the original rod action. Almost everyone likes the PHY Midge taper at 6' 3". If you were to extend that taper to 8', or even 7' 6", you would want to question some basic assumptions about the rod design. 3. Same as above goes for increasing or decreasing suggested line weight by more than a few designations. I think you can pretty safely go up or down 1 or 2 line weights without a lot of worry. With faster tapers, you can probably go down two or up two, giving a range of four line weights. For example, I think the Dickerson two piece tapers are pretty easily adaptable. 4. Keep ferrule sizes and tip sizes in mind as you make adjustments. Tips smaller than .050" can get tricky. Changes which result in ferrule sizes right at 1/2 of a 64th of an inch might need to have their flat to flat diameter increased or decreased a little, especially when using step down style ferrules. Moving a Dickerson 7613 down to a 3 weight, for example, could possibly result in a ferrule size that didn't make sense. There are exceptions to all the opinions above. The Leonard Tournament 8' 3 piece rod in Jerry Foster's Rodmakers page Taper Archive should not work at all. It uses ferrule sizes that make one think of a 5 weight rod. But it somehow winds up being a heckuva nice three weight. I don't understand that taper, but I do like that rod! (Harry Boyd)
I'm trying to keep up with you... Reading Wayne's page on Hexrod he states The Dimensions To determine the dimensions for the proposed rod design the total moments and the allowable stress values are placed into the following formula What formula??? (Ren Monllor) This is the formula, which is found at the top of page 258 in Garrison: Dimension[i] = Cube Root (Total_Moment[i]/(0.12*stress[i])) This formula is applied at every point _|_ (e.g.. every inch) along the rod. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive)
Hexrod has become a mythical beast that cannot be slain by man or computer. It’s one builder's lodestone and another's whazzat? My recollection is that Hexrod is the electronic version of what Garrison did back in the 20's. So its mantle is solid. Just as solid as the fellow that apprenticed under a well known and respected rodmaker. If drinking beer at the rodmaker's shop counts as apprenticing. And I suppose if the rodmaker shows the fellow how to open a can of beer all by himself, the well-known rodmaker is now the new guy's mentor. You can be whomever you want on the net. In the Garrison/Carmichael book, taper design is stated as, and I quote, "In truth, most of the successful tapers used by the great rod makers have evolved empirically, often as a result of their customer's preferences." And, "Men like Jim Payne knew what a fly rod should do in the hands of a competent angler, and his face would broaden in a smile as he felt one of his rods perform on the patch of lawn next to his shop...." Finally, and tellingly, "He (Garrison) experimented with, and ran calculations against, tests that he made between the years 1927 when he first undertook the job and 1933 when he finished the first pair of rods that he was satisfied with;" Five years till he built two rods he was happy with. Hardly the same as punching in a couple of numbers on the computer and coming up with your eight foot six inch 8 weight based on a Payne 98! Taking a classic taper and inputting it to your computer and stretching it 6 inches is NOT charting new ground. And putting your name on the "new" taper to boot is, well, just wrong. A well known fly fishing writer recently stated that there are only about 30 good tapers. That is closer to the truth than most care to admit. Because they ain't on that list. And again, today, another fiber is woven into the mithril-fabric hide of the Hexrod beast: that it is somehow tied to avoiding getting a set in the rod. Using Hexrod will avoid getting a set in the rod? I for one will not buy into that. Period. There are known reasons for sets, and unknown reasons. Hexrod isn't involved in either. "Show me the stress curve, and I can tell you how the rod is going to cast." Nope. Hexrod can't do that, either. What Hexrod does do is allow people who have not made a particular taper to talk with authority about its characteristics. Garrison states in his book that heat treatment caused significant differences in his calculations. If your process is not the same as the other guys, your are talking apples and oranges. If you have not made the rod, you really aren't part of the conversation! There was a book in print not that long ago that had dozens of tapers listed, with the advice somewhere along the line that the designer of the taper hadn't really built that rod, but it should be a good taper. Now this, to me demonstrates sheer mathematical or engineering genius, or the fact that it's really hard to screw up a taper unless you ignore the slope you created. I think its hard to screw up a taper, as long as you heed what is in Don Anderson's article. About slope. The first knight in this mythical kingdom flamed the outside of the culm, split, straightened, planed and glued up with epoxy. The second knight, concerned over a station 15 inches from the tip, added .001" to each strip at that point. Then flamed the culm from THE INSIDE, soaked it, planed off the OUTER dense power fibers, and then used PU glue. Garrison thought that adhesives and heat treatment made enough of a significance to include them in coming up with his calculations. Point is, the rod overall was changed more than just .002 at one station. And all those other changes were ignored. So the .002 of an inch was irrelevant when all else is taken into consideration. Kind of like walking up to the chalkboard and dotting an I. For those that have not read, or can't remember reading Don Anderson's article on the slopes of rods, I would point you in that direction. Too much slope, broomstick. Not enough slope, noodle. Finally there are good reasons that different rods of the same model mic out differently. And it is not just because of different people measuring differently. You think a cutter never got taken out and sharpened? You think an adjustment was made that created a little difference in the diameter of the rod? You REALLY think the greats worked to .001" or junked the rod? It's too bad that a few people's ego's wreak such havoc with a new builder. It is a stick that casts a string. (Chris Raine) That certainly was a nice post, I think you covered about most all the bases, however I not sure I agree with all of your conclusions. In fact I would like to take you up on the values of Hexrod and what you can do with it. Pick out your best taper, hopefully one that is not common and sent it to me and let's see what I can tell you about it. Just the taper, no name or line or anything else. Should be fun. (Bob Norwood) I find this discussion interesting. That said I have never looked at Hexrod and have only glanced at the section on stress curves in Garrison. It is rather like the difference between Garrison's ( or Wayne's) book and say Jack Howells. The first is written by an engineer, the second by an artist and there is a difference approach and respect for math and science. Neither approach is more right or wrong then the other. Some of us are confident in the science approach and are confident in using it. Others prefer an imperical approach that means looking at and handling a rod and "Knowing" what sort of action it is likely to have and roughly what weight range it will be. I respect those who use stress curves and Hexrod, I even enjoy much of the discussion on these subjects. That said, I do not intend to use them (I think, I might get converted one day). I guess these differences are what make the list interesting and we should all remember that from time to time when differences become fractious. (Ian Kearney) Hexrod has it's place but it's just a tool. You compare engine output by jumping behind the wheel of a car and do a quarter mile and you can read the specs. If you read the specs first you'll know if you'll need a drag shoot or if the cars are in the same class. (Tony Young) Twas thrilling and the stressful curve Did dance a jig to the taper sheet: All flimsily did the logic swerve Till Chris shot it in the feet. (Stephen Dugmore) (apologies to our resident poet, Peter) Hear! Hear! Well done that man! Cheers! (Peter McKean) I don't know if Chris is looking for a semiserious discussion of this or just trolling for cheers and jeers. He is using a lot of trolling language. There are two ways to criticize Hexrod, or more generally stress curve analysis, as a rod design tool. One is to say that, from an engineering point of view it is inadequate. It doesn't take much of an engineer to see that stress curves do not come close to capturing what happens when a rod is flexed, let alone cast, double-hauled, etc, etc. There are some engineering papers that work on this. There are some people on this list who occasionally that say they are working on the holy grail, a rod design tool based on good engineering, but so far it hasn't appeared. Or maybe they are just keeping to themselves. Or (in one case) they figured it out then lost the program and have been too busy elk hunting to recreate it. The other criticism, which Chris is making, is to say that the taper is not important, compared to the other factors that enter into play. That's a pretty broad brush. One thing that Chris says is that "So the .002 of an inch was irrelevant when all else is taken into consideration. Kind of like walking up to the chalkboard and dotting an I." The person he was referring to had taken into consideration "all else." He had built at least one rod with his method of flaming, planing and gluing, thought the tip was too weak, so he added 0.002 at the 0, 5, and 10 inch points and concluded the rod was better. He was not comparing his rod with new dimensions to someone else's rod. Now at the tip where this is happening, the rod (Wayne's 7ft 4wt) is 0.068, 0.070, 0.082 at 0, 5 and 10 inches. Adding 0.002 to each of these stations will increase the stiffness of the rod at the tip (which is proportional to the dimension squared) by about 5%. That's not large, but its more significant than "dotting an I". Another point he makes is that " "Show me the stress curve, and I can tell you how the rod is going to cast." Nope. Hexrod can't do that, either. " There is a two-way relationship between the rod taper and the stress curve. You take a taper, add some information on the line weight, length of line cast and ferrule placement and weight, and you get a stress curve. It works the other way too...take a stress curve, specify the line and ferrule info that was used, and you can get the taper. So people who say "Show me the taper ..." or "Show me the slope and I can tell how the rod is going to cast" are just as deluded as the stress curve people. And another point Chris makes is that "Finally, and tellingly, "He (Garrison) experimented with, and ran calculations against, tests that he made between the years 1927 when he first undertook the job and 1933 when he finished the first pair of rods that he was satisfied with; ... Five years till he built two rods he was happy with. Hardly the same as punching in a couple of numbers on the computer and coming up with your eight foot six inch 8 weight based on a Payne 98!" The point as I understand it is, that after Garrison work out his stress curve analysis, he could evaluate a taper before it was built, and see if it met his criteria. After 1933 he was able to use the math to design and build rods at a rate greater than 2 per 5 years (and still hold a day job). I think anyone who has built a few rods realizes that there are a lot of factors besides the taper. We have a lot of people trying to get to the bottom of heat treating, Same for node treatment. What I'd like to see, personally, is a scientific analysis of the natural variability in the cane we use. (Milward has some of that in his book). I know some builders claim to discard 3/4 of their culms as substandard. Other guys discard 1 in 10. Once you are done with the planing and heat treating and gluing, is there really much difference between the top grade culm and the middle grade, or has it all been planed away? Another issue is guide number and placement. Most rods will cast better with more guides than fewer. But we really don't know how to incorporate guides into the design of a rod. Someone in the early days of this list said "The taper's the thing". Its not the only thing, but most believe it is an important thing, along with the natural variability in cane, heat treating, node treatment, glue and everything else. We just disagree as to how to rank these factors. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) You wrote Hexrod as I recall, I want to thank you for this. I think Hexrod is very helpful and a real service. I appreciate it a lot. I thought I might say so to you. This discussion that happens from time to time is sort of a glass-half-full-glass-half-empty deal. It doesn't tell me everything I want to know like, "I have time to build one rod this year so which one will I like," but I suspect the next program that comes along won't do that either. It just does what it does....and, I think that's okay. (Timothy Troester) Well, my online Hexrod is based on Wayne C's DOS version. The first to take Garrison's math and put it on a computer may have been Don Wittekind who used to make a few cane rods in Columbus OH. He had a version running on a very early pre-DOS PC by maybe 1980. Don gave a talk on building cane to our local FFF club, Central Ohio Fly Fishers, about that time. I suppose that's where I caught the bug. He learned strictly from Garrison's book. Later (mid 1980's) he had a fly shop in Columbus. Anyone have a Don Whittikin cane rod? Funny the stuff you remember from 25 years ago. I have no idea where I parked this morning. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) I was just reading some old posts and came across one you wrote on ../06 where you stated that those people who say show me your taper and I'll tell you how the rod will cast were just deluded, well I for one would like to differ with you. As a matter of interest I would like to take you up on it, send me your taper and I'll tell you how your rod will cast. I have offered to do this before but as yet have not been taken up on it. So I am still waiting. I don't need anything else, just the taper will do nicely. (Bob Norwood) I don't know if the list is ready for another round of this or not (booo hiss cabbage ...) I'm strictly in the middle on this...the taper is very important but so are other things: quality of cane, heat treating regiment, type of glue, ferrule construction, number & placement of guides. And of course the idiosyncrasies of the caster. When you say "I'll tell you how the rod will cast" what exactly will you tell me that I can't guess just from the length and recommended line weight? Without knowing the quality of the cane etc. etc? (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) Send me the taper and I will tell you about your rod maybe not how it will roll cast, I'm not into that as yet but I'll tell you the general action you should get and will even send you a graph of what your rod looks like. One you can understand. As I said before, I went through this one other time but got no response. I hope you can do better. You seem to have had a lot to say about My state of mind, deluded I think you said. I would like the opportunity to respond to that and show both you and the list that there are many ways to evaluate rod tapers. All I need is your taper, perhaps one you designed, with the dimensions from tip to butt in 5 inch stations and the number of pieces for the rod, no step ferrule please. If you will not send one perhaps there is some brave sole out there who will. (Bob Norwood) In support of Bob I have to say that it seems a bit strange to me that someone would go to all the immense trouble of learning the craft of cane rodmaking without mastering the elementary and essential skill of being able to interpret a graph of a rods taper or stresses into a reasonably accurate description of that rods action. If you cannot do this then you must be wasting a lot of time and money making rods on the supposition that sooner or later you will make one that you like for a particular application. Would it not be quicker and cheaper to design or modify a design in such a way that you have a good chance it will do the job on the first attempt? And on the third it should be perfect, it is very hard to predict a line rating exactly from a graph, although you can get near enough, and cane is very tolerant of line ratings anyway due to its comparatively high inherent inertia. Greenheart more so. Modern carbon almost totally intolerant! I suspect that most of the experienced rodmakers on this site can very easily predict a rods action from its dimensions and graphs. (Robin Haywood) OK, here are tapers for 2 rods. The first is 8’ 2 pc the second 7’ 9” 2 pc. The ferrules are in the middle. One of them is my favorite all-around trout rod; the other I just don't like at all but I use it once in a while for fishing bluegills. Now these are the tapers on paper that I built to. I'm not inclined to go back at this point and mic them. I went back and read my post from the date in question. It was in response to Chris Raines. In my own defense, I never intended to call any specific person deluded. It was a complicated discussion about whether the stress curve or the taper is more informative. I'm sorry if it came across as aimed at you or anyone else. Rod #1 00 062 Rod #2 00 080 Thanks for the tapers and the explanation, I appreciate that. Your first rod, the 8 ft 2 pc is a interesting taper. It is what I would call a positive slope rod. It has a soft or weak tip for the first 15", but then the tip gets stronger in the middle and somewhat softer in the lower tip and upper butt giving it an area of flex even with the ferrule there. From 50" on down, the butt gets much stronger, so much that the butt swell at the handle is really not needed unless you like the looks or the feel of the added weight, for I think the action stops well before the swell. As I look at each section of the rod I would say that the tip is a 4 wt and that the middle of the rod is a good 5 wt, but the Butt is as strong as a 7 wt, this is what I mean by it having a positive slope. I think you could use a 5 wt line in close to maybe 35-40 feet and make use of the soft tip, then a 6 wt DT if you want longer casts. If you really want to use the strong butt I think a 7 WF line and a double haul will shoot a good long line, but it will take good timing to do that. I think I would like this rod and would use it for trout or also for small to medium bass and I think it's the one you like. I will send this to the list and a separate one with the graphs attached to you,. The Graphs are in Adobe and take up about 25 K of space. By the way the taper and stress curve are pretty smooth, by that I mean they have few bumps in them. I like a smooth taper, I feel that it transfers the rod power and stress in a smooth manner. I will do the second rod a little later. (Bob Norwood) If anyone is keeping score, my first rod is the Dickerson 8013, 1949 version, from Howell's book. Except that Howell suggests that .004 be subtracted for varnish on the tip & .006 from the butt and I just subtracted .004 from both. I fish it with a 4WF. This rod never suited me. It seems too floppy in the tip and too stiff in the butt. Now it may just be a poor execution on my part; lots of people seem to think the 8013 is wonderful. Maybe I should have sprung for a step-down ferrule. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) The next time you get the urge to build an 8' 5wt, try the 8013 in the archives instead. I've made both the versions in Howells book and the one in the archives and the last is by far the best one, IMHO. (John Channer) What's the varnish subtraction factor for the taper in the archives? (Henry Mitchell) If you look at the listing in the archives you'll see that Tom subtracted .005 for varnish already. (John Channer) Here is rod taper #2 First of all it's a strong rod, I am looking at it as a 8 wt but it may be more of a 6/7 because of the deep flex area in the upper butt and lower tip. The upper tip is a straight taper for the first 15" but then it has a very strong hump in the middle and lower tip which will stop the tip from flexing much at all. It looks like a Parabolic rod except instead of continuing to drop off into the butt, it starts a very steep butt swell making most of what action there is, stop at 70-80". The rest of the lower butt will flex little or none because it's so strong. The one area of flex is from 45-65" and I think this will make the rod feel like there is a hinge in it. I am trying to find some good features that I can point out but, I guess the kindest thing I can say is that you will always find someone who likes a rod. (Bob Norwood) And the rod I like is a modification of the Cross Sylph in the Hexrod > archives. The original is listed as a 5 wt. I built one as specified, then built a second stretched by 3 inches and increased to a 6 wt with Hexrod and made a little heavier at the tip. I use it fishing weighted nymphs & streamers; and for the Hex hatch. I really like the way I can lift the line with a roll cast after a long drift with a nymph and shoot it back with one backcast. I use a TT 5/6 line; I think the strong middle makes it pretty forgiving of line weight. With a light line its a fast rod and with a heavier line its more parabolic. That's my theory anyway. Maybe I am the only one who would like it. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) I appreciate Hexrod. I have gleaned helpful info from Hexrod. I also understand Hexrod doesn't give me every tidbit of info about a flyrod or taper. It makes me think and it helps to visualize. Hexrod also gives us a common vocabulary so we can talk to each other. You know there is a special wiggle that some fly rods have that sends shivers up my spine. I will test all fly rods for that thing. I tend to like rods that do that to me. I am not sure I enjoy fishing with every rod that has that special wiggle every time or at all. I like knowing it is there. You know I have a winter rod I have never fished. it sits by my chair in the living room and in the winter I will sometimes pick it up. that special shiver takes me to the river for a moment. Now this wiggle b***s*** isn't at all scientific. but it is important. some of you engineers, scientists and mathematics guru's may not get that but that doesn't mean i am an idiot any more that the high math means you are over complicating rods and splitting hairs. Hexrod has helped us to talk to each other and learn something from one another. Fact is, I think, we are all nuts! in the words of my deceased father in-law "any man that has time to go fishing has time to get another job and make something of his self!" So, who's right and who is a bum? I do not know! what I know is that pursuing brook trout with that special rod is a sort of insane pleasure. Even with the science I have learned things about myself and stumbled across some valuable truths. I have met some incredible craftsmen and unforgettable characters. I have made some great friends. these are things that make up bamboo flyrod building in my life. Some of these things I can not use a slide rule on or calculate with a program I wrote myself on the computer. I hope you can learn something from me. I have learned so much from so many of you. (Timothy Troester) Frank brings up some excellent points. And, after reading his response, and some others, I feel I did not do a good enough job explaining myself. Frank, thank-you for responding. Firstly, my post was a troll of sorts. There is a lot of info given out to those new to rodmaking that is confusing and conflicting. Sifting through those posts makes me feel that there are a bunch of builders eager to help and provide answers. There are also, obviously, those that use a question to the list as an opportunity to pound their own breasts. To the detriment of new builders. The straw was Hexrod being touted as the tool to avoid sets in rods. Newcomers pour over these posts to glean new info. What they need is factual information. Writing a post as long as I did put me past my normal attention span. I feel that the taper is the heart of the rod. Somehow I completely failed to make that point. As an empiricist, I feel that building the rod, be it 2 different butts and 3 different tips and working from there until something better happens is my key to success. And I know that when I finally get something I really like, my measurements will be uncomfortably close to a rod built 50 years ago! I am being sarcastic in this sentence, but looking at all of the info and misinfo lately, a new rodmaker, wanting to design the cheetah of a flyrod could end up with a giraffe instead. In my opinion, holding work in a planing form or power beveler or saw (we are talking about a floppy piece of bamboo here) and cutting it to plus or minus .000" (builders, some of them, claim this feat) is impractical for both the new builder and those that want to make a number of rods. And would bring a chuckle from most machinists, I imagine. This goes hand in hand with the claim of having no "spine" (not "spline") in the rod or rod sections. Some builders on this list claim they would junk their rods if they could find a spine. Good thing that wasn't the philosophy at Granger or Phillipson. Or Payne. Or Garrison. Or any of the rest. There is also a thought on this list expressed on a regular basis about what makes a true rodmaker. Number of rods, whether you make your own ferrules, reel seats, grow your own bamboo, etc. IMO, you are a rodmaker when you finish your first rod. Just as is the rodmaker that finished his hundredth rod. But each maker, at his point in time, has a different set of questions. I appreciate your response, Frank, and I do know that you and others are working on programs that will answer your questions on rodmaking. Again, my reason for the post was to let new makers feel that their efforts are not inadequate, nor will they be unable to build a rod they are happy with, having their current skill set. It is a stick that casts a string. (Chris Raine) As a new rodmaker I find these posts about Hexrod, RodDNA, Stress curves, and tapers interesting and sometimes informative. To me though it seems to miss the point. These are tools to make rods, just like planes, forms, and ovens. They don't determine what is a good rod. As a fly fisher since I learned the basics from my Dad when I was ten I know it is not the numbers that make a great rod, but the art of how it casts. As craftsmen we know it is that art we strive for and not the perfection of the engineering behind that art form. If you let ten people fish the same rod you will get ten different opinions on that rod. A fly rod is a personal thing for each and every one. Keep up these discussions, because I am learning much about the tools of rodmaking, but that is what they are. They don't define a good rod though. It is the art of fishing that rod that defines it. Like all artists we have different styles and influences that truly define what is great, and for each of us it is something different. Like Michaelangelo and Picasso, two very different styles and techniques, but both are great artists in their own right. One may prefer one over the other, but one can not deny the artists talent. The engineering of a taper, stress curves, precision of a cut are all involved in making a great rod, but it is the art of the finished product when used that truly defines it as great. (John Wild) The curves really are very useful, all we have to do is look at them and see what we can expect. If you had 10 different people cast the same rod none of them should find it to be parabolic when it isn't for instance and they should all agree that the rod has a stiff butt and fine tip action also for eg. These are the things you see in a curve that you can't really determine just by looking at numbers. What you can do with curves from there is up to the individual but they are worth a few moments study at the least. (Tony Young) I didn't mean to come across as saying that stress curve analysis was useless. Having a engineering background I find valuable information in studying the stress curves of various tapers, and have learned much from them. They do provide us with what an expectation of a rod's performance and whether it has a fine tip action and stiff butt. These stress curves are a valuable tool from which to build and design a rod. Considering the nature of bamboo rods: natural materials, varying techniques, etc.; these stress curves don't define the final product though. They are a foundation on which we build rods, whether individual builders study them and use them or not, but they don't define each individual rod because of all the other variables involved in construction. A builder can learn a lot from studying various curves, and they can be used to design a rod to a certain expectation. It is the final product though that defines defines whether or not those expectations are met. This final product is the art of a craftsmen, regardless of the underlying engineering. (John Wild)
Where I've heard about Hexrod for the past three years many times now it's one of the areas I just don't get. I'm wondering what would happen for example (to the taper/action) if one were to take a Dickerson 8615 and set the Hex program to adjust the taper out to an 80 Ft casting parameter. Anyone have a clue about how that might work and how or what the rod would look like. Would it give more backbone to the rod, would it make the rod look like a broomstick? I just don't have a clue. (John Silveira) I think that you would have a nine or ten weight rod. But that raises the question as to whether the distances in Hexrod are really the length of the cast, the length of line that can be lifted from the water or the length of line you can aerialize. Monsieur Stetzer? (Henry Mitchell) Henry is correct. You would probably get that nine or 10 wt rod. All that matters to Hexrod is the total weight of the line beyond the rod tip. The actual length out there is irrelevant. Whether you or I could cast it or lift it from the water depends on things that Hexrod doesn't account for, including the skill of the caster. I don't think you can use Hexrod, or other stress curve-based systems, to make big changes in a rod. They work by "holding the stress curve constant." The family of stress curves that make a nice 7’ 4 wt are probably not going to work for an 8’ 8 wt. Would be an interesting thing to look into, someday. I think that AJ Thramer's PX tapers are parabolic. The DX are the faster "Catskill dry fly" tapers. He posted quite a lot of tapers to this list in 1998. You can find them in the archives. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) I think the 8615 is more than capable of 80' casts. Like me, Harry has a fondness for Dickerson tapers and being a certified casting instructor, he's capable of throwing more line than I am <G>. Maybe he'll chime in on the 8615s' capabilities (heck the 8014 Guide is more than capable of throwing in excess of 80') or were you looking for stress factors @ 80'? (Will Price) I'm just completely in the dark about that hex program. I was thinking if the 8615 for example - just "felt" still a little soft would bumping the length of line on Hexrod make the rod a little more stout? It was mostly just a curious question. (John Silveira) Yeah, bumping the length of line will beef up the dimensions. I think if you beef up the rod a "little" though, I would beef it up less than that. Just my opinion, there is no way to tell for sure until you build it but I would try an additional 20' of line. If you add too much I think the rod could be "like a pool que" if you are planning to cast it consistently at 40". Another point...I think Hexrod interacts best with more straight line tapers. This could be because some tapers just do not translate to different purposes other than what they were created for. I have a 6'10" Hardy Phantom taper that is a wonderful dry fly rod. Send zooming narrow loops well into a stiff wind. I found out that stepped down to a 3 wt, while impressive to see a 3 wt careening line into the wind, has very poor accuracy. This is a great rod for picnics and county fairs but I would pick something different for fishing. (Timothy Troester) Don't think I've ever had the chance to play with an 8615.... at least not a real Dickerson version. The 8014G and the 8015GS are both super rods, IMHO. (Harry Boyd) The 8615 could throw ME 80'!!! Muscled a 16# Steelhead in with mine a few years ago and fished it as a 7wt. I like it as is. (Eamon Lee) Eamon's smiling face is above a big steelie with that rod in a former "Planing Form" picture. Is this the creature in question E? If I remember correctly, the caption is something on the order of "who says bamboo is just for small fish" or some equally challenging remark. Oh, while we are at it, was that the 8615 listed in Howell's book? Just curious, as he recommends a 6 wt. and states it isn't something you'd use for steelhead. Guess you would! (Carl DiNardo) Howell's version of the 8615 is a six weight with a (varnished) tip of .073", and is a six weight. In Tips and Tapers Ray Gould lists the 8615 with a .094" tip, I don't know if it is varnish-adjusted, but rather doubt it. Obviously these are two completely different rods, despite the same name. I built Howell's version and it can be used with a seven line, but fishes best with a six. I don't think I'd want this for steelhead (never having fished for them) but the other versions look like they'd be up to the task. Despite being called a seven-weight, I thing that the 8015 Guide Special would make a great 8'-8wgt rod. (Henry Mitchell) That taper was off of Frank Stetzer's site. And yes, I pushed the envelope with that one. Smaller fish were around at that time and I was hoping to tie into one of them, but a big fat hen beat them to it. I tried a 6wt on it but I never liked how it loaded. (Eamon Lee) Yes I have built this rod and like it a lot. It is more a 5 or 6 weight in my opinion rather than 4 or 5. It can handle big water without the extra heft. Just my experience. (Frank Paul) I have had a chance to cast both of Sante's 8014G and 8615 originals. Both were very amazing rods with a 6 and 5 weight lines respectively. Their tapers were slightly lighter than those listed in Howell's if I remember correctly. If John's looking for an 8wt, perhaps Gillum's 8'10" taper would fit the bill. I believe this is the same taper the west coast guys are Hollow Building for Steelies. I have an original 9016 that is a true seven weight, but the other 9016's I have cast and mic'd were heavier in taper and were 8 or 9wt's. Casting long lines is more the skill of the caster as I have seen the backing on the 8014G and 8615 in the right hands, I can't but it can be done! Personally, I am trying to decide between 8615 or an 8015 Guide. Have a 16/64 SD half set and would like to put it to good use. I am in the process of making an 801610 5wt, so I'm leaning toward the Guide for casting Dalberg Divers and large streamers for the inhabitants of the Potomac. (Tim Pembroke) Here is link to an 8 weight taper from Chris Obuchowski. I've made this and I like it. Being 8’ it doesn't take quite the toll on my arm that a longer rod does. That may not matter to everyone. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive)
I have been looking at some tapers in Hexrod for my next few rods. Was wondering why there are differences on some rods on butt versus tip numbers. Let me explain: Young Perfectionist>> Tip at 40-.192 Butt at 40-.192 Young Boat Rod>>>> Tip at 40-.207 Butt at 40-.172 Seems like a problem. I understand adjusting for stresses and ferrules but is this right?????? (Barry Janzen) I assume this is about the planing form settings. I should add this as a FAQ to the Hexrod web site. The ferrule on the Perfectionist is at 48in. The dimension @48 is 0.232. The Hexrod planing form settings for the tip & butt are calculated to give you the correct dimensions at 45 & 48 on the tip and 48 and 50 on the butt. What is beyond them are just extrapolations. You don't really care what the butt setting at 40 is anyway, but you want to set 45 so that 48 is on the mark. I hope this helps. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) Something seems to be off. Ideally, if you extrapolate the values to 48 inches they should be the same. On the tip section, if you extrapolate to 48 inches you get 0.238. On the butt section you get 0.224. If the numbers were transposed you could make a case for a stepdown ferrule. (Al Baldauski) Something else weird happening. When I click on the "Dimensions" button next to the "Modify Rod Design" descriptor, the next page that pops up is a "500 Internal Server Error" page, with this explanation: "The server encountered an unexpected condition which prevented it from fulfilling the request. The script had an error or it did not produce any output. If there was an error, you should be able to see it in the error log. " Not sure if this is related to the dimensional problem on the Boat Road. The other three buttons to the right of the descriptor work as designed. (Mark Wendt) When in doubt or just to be sure, just go to the original post and make your own mistakes. No ifs, no whats and only one butt. (Larry Blan) I just looked at the taper in David Ray’s library and the station values are the same from stations 40 thru 55. There is a steep slope in the taper as you approach the ferrule from the butt end. If Hexrod extrapolated the values from station 55 to 40 from the butt end using that sudden drop in diameter then it will give values at 45 and 40 that are much too small to mate up with the tip section. The comments suggest the measurements were from an unvarnished rod with no mention of a step down so we can only assume a standard ferrule was used and the stepdown occurred in the bamboo between stations 55 and 50. (Al Baldauski) You've had several responses, Frank came closest. Many old rods were built with what's known as a drop over the ferrule and everything built before the end of WW II had either Leonard/Payne style ferrules or drawn ferrules. Of the two, drawn ferrules were made several ways, some had a 1/64ths difference between the female and the larger diameter of the male. In any case, the ways to deal with it now are to either use the settings that Hexrod gives you, which smooth out the taper thru the ferrule area so you have the same diameter at the ferrule ends of both the tip and the butt, or do a little math and extrapolation and figure out what the dimensions really were. In the latter case, use the ferrule size(of either Swiss or Leonard style) that fits flat to flat, then you wind up just taking the corners off the male side. I hope this is a bit clearer than mud. (John Channer) You are correct...Frank came the closest to mind reading! Actually, I was rushing to get off to work and had a better email composed and it vanished. Had to retype it and guess I didn't explain as well. Sorry. Yes I am asking about the FORM SETTINGS numbers and I understand that they are extrapolated to help with transitions. However, I have adjusted several now at the forms and was wondering if there was a problem or if I was doing something wrong. Of the five tapers I have printed out right now on my table, this one seems to be the most off. (Young Boat rod) Now I understand it is "right" but it seems wrong. Should I adjust for a smoother section? The numbers again: Tip>>> 40- .207 Butt>>> 40- .172 NOW....0.232 is stated as the size at 48" for 14.848/64 ferrule. Now I know that it will be "right" at the end but it seems like a drastic transition that should be smoothed out. 20-30 thousandths jumps seem steep. Shouldn't between 45 and 50 be almost level for better ferrule fit? I haven't tried my forms yet but they are set for 10 thousandths standard drop over 5 inches. This is 32 thousandths between 45 and 50 on the butt section. I try to view the taper as one complete rod section but maybe that is wrong. This is why the numbers look funny to me. I know I am still new at this but I want to understand it better. In my opinion, station 40 on the butt section should be close to the size of the tip for a smooth ferrule area. Maybe this is normal and I should just go back to building ;-) (Barry Janzen) In this case I think the taper as written is screwed up, somebody has mismeasured or entered a typo into the program. Where did this taper come from? The butt section numbers are smaller than the tip (which I'm sure is what prompted this thread in the first place) and that should not be. Here's the one from the original post from Rob Hoffhines that are in both Franks archives and David Ray's. Rod Name PHY Boat Rod Length (inches) 96 Comments Paul Young Boat Rod - 8’ 6 wt 2 piece Posted by Rob Hoffhines Aug 18 1988 ''A strong butted 8’ 6 wt. Contrasts the Para15 nicely in the Young lineup.'' From an unvarnished rod. Deduction for varnish 0 0 0.074 0.037 I think I see what happened. You've given the Hexrod numbers, the program seems to have extrapolated the slope from each section where they overlap. There is a sttep ride on the butt side of the ferrule and the program has followed this slope thru the ferrule into the tip section and the same for the tip side, it doesn't slope as steeply so they appear to go off inot the ozone after the intersection where the ferrule goes. You can set your forms to the numbers given, just make sure you cut them in the right place when it's time to mount the ferrule. I usually ignore what Hexrod says about the overlaps and just set the taper in the forms as if it was a one piece rod with no ferrule, then start planing at the back of the form and move the strip up as I get flush to the form. (John Channer) Last night I looked at the way Hexrod is computing the planing form settings, at the ends beyond the actual section length. I think the method I'm using is working for many rods but not others, like the Young Boat. I'll have to dig into this a little further. Thanks for pointing this out. I'll let you know when its resolved. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) I made a change to the way the planing form settings are extrapolated past the section ends, basically changing the points I was extrapolating from, and I think it will resolve the issues. The form setting at the end of the section should be correct for the rod at the ferrule station. See if this seems more reasonable. Let me know if there are any problems; that goes for all the Hexrod users out there. Planing form settings for stepdowns should always be approached with caution; the Hexrod math really doesn't like discontinuities. Now back to my paying job. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive)
The list is kind of slow, so I thought I would ask a stupid question that has always bugged me about entering taper dimensions in Frank’s Hexrod as they are listed in Howell’s book – kind of backwards to me. I always got around trying to figure this out because many of the tapers are listed elsewhere, but I have always been a little confused by this, which is nothing new for me. For example, take the Dickerson 8014G as shown in the Howell book (without the .006 varnish deduct): BUTT TIP 0 .375 .224 What I was originally trying to do was smooth the taper out at the ferrule station because of the huge drop with out having to use a step down. The numbers don’t work out right for me. Even if I enter it in 5” stations starting at 0 to say 95 in Hexrod, it is not even close to the same taper. What am I missing? (Tom Vagell) Converting from Howell’s system to Hexrod or other measured from the tip systems odd the first time. There are 2 issues: reversing the measurements and deciding what to do with stepdowns. Here is how I do it: The measurements for Hexrod will be: station dimension -------------------------- 0 .084 So at the ferrule I fudge the station 0.5 inch on the butt (female) side. If you want to smooth the rod to fit the ferrule, you will pick the appropriate ferrule size first, then change either the butt or tip or both to fit. I don't think there is a formula to change from stepdown to regular ferrules, except to use your common sense. (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive) Through the magic of Excel, here is a table which might work. It already has the taper smoothed across the ferrule. I will send you (off list) a PDF showing the graphical relationship between this taper and the numbers you give below. Station Taper 96 0.375 Thanks so much for the input. At first it was clear as mud, but I think I’m getting it and in the process realizing that I don’t understand taper design, stresses, and the graphical relationships as well as I thought. I had surgery on my arm (ulnar nerve transposition) about six weeks ago and can’t work on some aspects of rodmaking anyway, maybe not for a few more months. I am going to use that time to really study taper design and stress curves through the books I already have. Admittedly, it has been way to convenient for so long to copy commonly available “famous” tapers – not that there is anything wrong with that – I just think I should have a more solid understanding of design and related math. Anyway, I may have some more stupid questions, so thanks in advance for your patience. (Tom Vagell)
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