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While Garrison did us all a great service, he also did us a great disservice in making us think we could reproduce any taper by measuring at 5" intervals.  (Jerry Foster)

    I agree that an exact replica could not be produced with measurements at 5" increments.  But I suppose it depends on what you're trying to replicate, the action or the taper.  I don't know how to quantify the relationship between the taper and skill of the fisherman.  But at least 50% of the action might be attributed to casting skill.  I expect that's why Garrison and many others are comfortable designing tapers with 5 inch increments.  Every taper has multiple personalities depending on the skill of the fisherman, line weight, length of line fished, size of the fly, etc...  It's probably not practical to  design a taper for every cast.  They just need to be directionally correct within reason.  The rest of the game is pure skill.  That's an important point that's been lost in the fly fishing hype of the big companies that have done everything they can to convince folks that a new rod will significantly improve their fishing.  That's simply not true for most of us.

    I try to keep up with taper design discussions on the List.  That can be very frustrating.  Simple design principles seem to get lost in the details with 5 inch increments.  I can't imagine trying to follow a discussion in 1 inch increments.  FlexRod extrapolates 1 inch tapers from the 5 inch inputs before any calculations are done.  I use the extrapolated values to build out the form setup sheet for an infinite number of planing form increments.  The sectional taper chart (i.e. Split & Glued ch. 8 and 9) in FlexRod is compiled from extrapolated 1 inch increments.  Beyond that, I've spent a few years studying those 1 inch extrapolations and find them very difficult to analyze at that level of detail.  I can't imagine trying to design a rod in 1 inch increments.  Maybe I'll get there some day.  (David Bolin)

    OK, Jerry, I'll bite!  So far, I don't recall seeing flat-to-flat measurements from any of "the master's" rods that were the same at 5" intervals.  What would be the point of measuring (and trying to set a planing form) at shorter intervals?  Which strip is out, and should you try to duplicate the difference?

    If you are milling, I can see wanting closer measurements, but I'm not convinced it would make much difference in the big scheme of things for hand planing.  I sure wouldn't want to set a form at one inch intervals.

    For a mill, I certainly see the need for closer intervals to make your template.  Maybe a batten to smooth out the intervals like they use in boat building?  However, a steel planing form will assume a fairly smooth curve between stations anyway.  (Neil Savage)

      I wasn't trying to drag up the mill, hand planing issue here. I was just musing about loosing all the original tapers of the masters because of our measurement methods. It is well suited for "close to" reproduction to use 5" intervals, we just loose the nuance of the original taper.  (Jerry Foster)

        My point was that since the measurements from flat-to flat are seldom the same at any given station, I can't see that we are losing any nuances by not measuring oftener than 5 inches.  Garrison, we know, used a steel planing form, just as I do, so he at least didn't take any account of the smaller increments in his rodmaking.  (Neil Savage)

      Also if you check, to do one inch stations it requires tapers to be measured to 4 places to get the accuracy needed and most programs can't do this. I agree with you that 5 inch stations are more than adequate for all conditions. If you check, the one inch measurements are just the 5 inch station difference divided by 5 to get the one inch values ? I suppose this makes sense but I'm not sure how, you only need two points to define a straight line.  (Bob Norwood)

        I guess the argument is that if you design on 1 inch centers you can more accurately represent a curve instead of that straight line between two points.  As others have said, a steel or wood form bends to create a curve between those points so you automatically get it.  Those who have CNC mill need to program on one inch centers to get the curve that the forms automatically give.  But frankly, the small differences between a fair curve versus a straight line between 5 inch centers is averaged out and unnoticeable in rod performance.  (Al Baldauski)

          A question to explore the 5" measurement regime...

          The methods I have learned is to take measurements at the 0", 5", 10", 15" etc. stations, set my planing forms to the measures and plane away cane.  The forms do not deliver a series of steps that  are effectively smoothed out.  All well and good.

          Now, if I measure an rod at 2", 7", 12", 17" etc - still 5" increments - are the tapers of the old masters substantively different than by taking the measurements at 0", 5", 10", 15" etc.?  Has anyone on this list looked at tapers from this angle?  Or, another way of asking this, why are the measurements at the 0", 5", 10", 15" etc. stations seemingly the holy grail?  Jerry has started a random brain cell for me.

          From what I have seen of one old taper cutting device (Peter's at Corbett Lake), the contraption shaved off the bamboo strips by using a metal strip pattern as the shaping guide - basically a measurement per millimeter (OK, so I grew up decimal).  Seems to me, the old tapers were not "invented" at 5" intervals, but some (many?) were effectively empirical evolutions in which the success or not of the taper was in the fine detail.

          Not that I aspire to be that accurate, although I am definitely that anal  :)

          Musings of a tired brain.  (Greg Dawson)

        Could you explain why you think you need the precision of four places to the left of the decimal point to achieve accuracy on 1" stations?  I've got a copy of a couple of old Payne tapers, on one inch stations.  The precision in those tapers is only out to three places.  If you are talking about a modern day design, where the design was figured on 5" stations, then yes, you can divide the station difference by five and get the one inch stations.  But tapers that were originally done in 1" stations will not be the same.  (Mark Wendt)

          But I have never seen an original taper in one inch station settings, so it's very hard to comment on them. I have never found the need for one inch values since all I have seen are those where the one inch stations are derived from the 5 inch stations and all I have see of these have measurements given to only three places and then the one inch values are just as I have said, the 5 inch difference divided by 5 and added to get each one inch taper increase. To me this is a STRAIGHT line unless I am missing something. Both online programs use only three places and they jump by factors of .001 which is not accurate and gives a step type of taper rather than a smooth curve, some times the increase is .002 and the next .003. RDNA uses four places but here again the one inch values are calculated by dividing by 5; they are not derived values that I know of. This still makes them a straight line taper. now if you have Original tapers that were made on one inch centers, then by all means use them. I know I can't and would not even if I could, don't see any reason to.

          If you read the question I asked a while ago regarding the Garrison 212 tips, one built to the regular 5 inch stations and a second built to a zig zag taper where the station values were increased by .005 and the next one decreased by .005. I built both tips and I can't tell the difference, maybe others who are much better casters than I could. I did a static stress test also and there was no noticeable differences in the deflection curve or the tip value. To me this says that Bamboo is very forgiving and small taper differences are averaged by the long fibers. Therefore it is my belief that one inch stations are gross over kill.

          Now if you have some data that shows this not to be the case maybe you can bring it to SRG, I will bring my 212 with the two tips and we will have some fun, but I think it should be done in the morning or early afternoon to negate the suds effect, what do you think.

          Oh; I didn't answer you original question regarding the need for four place accuracy. Well if you have 5 inch stations and the difference is not easily divided by 5; say .013 which would be .0026 for each one inch station. The first one inch station will be either .002 or .003 and the rest would be the same, question is which one do you choose, either way the accuracy is still only to 3 places and no not as accurate as just a 5" to 5" station setting and let the form do the math in-between.

          If you share the taper you have I would be glad to comment on it, but it's hard to do so without seeing the specific taper, for all I know it may have been set up to negate this problem.  (Bob Norwood)

      "If you are milling, I can see wanting closer measurements, but I'm not convinced it would make much difference in the big scheme of things for handplaning.  I sure wouldn't want to set a form at one inch intervals."

      Has anyone considered the difficulty of putting adjustment screws at one inch intervals?  Sometimes practice controls desires. (Frank Paul)

        Correct me if I'm wrong (I don’t have the tapers in front of me) but your 3 200 rods had turnover points at 8, 10 and 18 inches. If so, for what it is worth, you could certainly tell the difference between a turnover at 8 inches and one at 10.  (Jerry Foster)

        There isn't enough physical room to put stations on a planing form at 1" intervals with a dowel.  Push screw and a pull screw.  If you were using a differential screw for the stations you could do it.  IF you could ever get the forms together that is.  (Larry Swearingen)

          I think there's a few form makers that do 2 1/2" centers on push/pull forms but it's usually only done for about 15" to 20" at the end of the planing form. I always thought it would be nice to have forms with 3" centers.  (Ken Paterson)

          Yabut...  Y'all seem to forget that not everybody is using planing forms or a MHM. (Mark Wendt)

        As I stated earlier, the differences in flat-to-flat dimensions as measured from old rods would certainly eliminate the need for .0001" dimensions, or anything close to that.  The differences are, in some cases over .005".  Just because your calculator will give an answer to 10 significant figures, the answer is still no better than the accuracy of the input data.  (Neil Savage)

        1" centers on any rod design is picking fly poop out of pepper. What is the point? You are not likely to cut strips any better than 0.001" and most cannot even measure any better than that.

        Is all this 1" design work to get a fair stress curve? If so, how smooth is smooth enough? If you are using some fancy computer mill then design on 0.500" stations or 0.100" stations if you want. Certainly possible with today's computers. There must be a point of diminishing returns. These are fishing poles we are making so lets not over-design the darned things. The final performance is the average of all the humps and bumps in the stress curve.

        A guy who is happy with 5" centers.  (Jerry Drake)

          Well, but then you have to ask yourself,  why did Mr. Payne, Mr. Leonard, Mr. Dickerson and others design their tapers on 1" centers?  Besides the fact that "they could..."  ;-)

          Like I mentioned earlier, remember, not everybody is making rods using a planing form or an MHM.  (Mark Wendt)

            You mentioned the greats - Leonard, Young, etc. built rods on 1 inch centers years ago. Could you provide the references for your statement so I can check them out. I enjoy some of these tapers and would like to compare the originals (not measurements by current rodmakers) so that I could make some comparisons with current available information. (Frank Paul)

              Well, didn't Leonard and Payne use some kind of mill to make their strips? In that case it would make some sense to design to 1" or less to cut the initial template.  Of course, you could use calculus and have the measurements as close as you want.  OTOH, what about the apparent flat-to-flat differences as measured from their rods?  Dennis Higham posted a Payne 101 in 1998 that had .003" variations at some of the stations.  If we take a taper change of .001"/inch, that's 3 inches?  That's why I don't think we need to be quite so anal about the measurements.  If I can get less than .002" at a station, I'm happy as a clam.  (Neil Savage)

                The sloppiness in their measurements flat-to-flat happened because the machines wore, and they didn't ensure that the machines stayed within tolerance.  And the technology of their machines is/was quite a bit old.  There are plenty of ways today to hold and stay within the tolerances we're used to working with - ±.001".  Should we, just because somebody else lets their tolerances slip, allow ours to do the same?  And if technology permits, shouldn't we be more exact, more precise, more accurate?

                I'm in the process of building a machine, and hope to be able to hold my tolerances to less than that.  Dimensioning the taper at 1" stations or less will help me achieve that goal.  (Mark Wendt)

                  The perfectly tapered rod, with perfect guide spacing, guide sizes, ferrule size, ferrule type, bluing or not, reel seat hardware, reel seat insert, cork quality, grip style, winding check or not, tip top, thread size, varnish, thread material and thread color would be a very cool rod.  But finding three talented fly fishermen (not collectors) that agree that it's THE perfect rod might be impossible.

                  Our preoccupation with making the perfect rod is a maker thing.  It has little to do with the task it was designed to perform.  But it's still worth pursuing so long as it adds value to the rod making experience.  Just don't get caught up in the hype that dominates the fly fishing industry.  The big dogs of fly fishing sell tackle that they say will magically improve the casting skill of the poor guy that fell for the slick advertising.   I know that to be true because I've been that poor guy a few times.  I know better now, but I'm still tempted.  (David Bolin)

                    Never said I'd like to make the "perfect" rod.  I did say however, that my goal is to make the rod that's the most accurate and precise according to the taper I'm working with.  It's up to the individual using the rod to determine if that rod is "perfect" for him or her.  (Mark Wendt)

                  Did You read my post on the tip test I ran with the regular Garrison 212 tip and the zig zag one ? I could not tell the difference between tips and the static stress test didn't show any either. Now this is a difference of .005 +- from each station all the way down the tip.

                  Are you sure you need one in settings?  (Bob Norwood)

        One other thing I'd like to mention.  It all goes back to the "Bible" - Garrison designed his tapers using stress curves.  He figured out all that based on 1" increments the length of the rod.  If 1" stations are overkill, whey don't we average the sections at 5" points and be done with it when we're working out stress curves?  Why? Because we're concerned with accuracy, precision and resolution.  (Mark Wendt)

          I would have to disagree with you on this one. Garrison used his stress curves to insure that the stresses were as he wanted at the line length he selected. So what waged what; I think it may have been a 50 50 relationship to him. He was concerned with both stress and also the taper design. He talked quite a bit about tip and bounce which is a design feature, but always made sure that the maximum and minimum stress were within his design limits.  (Bob Norwood)

            My point is,  he figured the stress curves using 1" stations.  If we truly wanted to add precision to our taper designs, wouldn't we also want to design the taper using those same 1" stations?  Or are we relegated to measure with a micrometer, mark with chalk, and cut with an ax?  (Mark Wendt)

              I really have to agree with Mark here. I realize most people on the list are happy using planing forms or at least cannot afford the cost of a CNC milling machine or beveler or even the expense of a non CNC machine. Many of us are tinkerers though and quite a few home made machines exist. This is the rodmakers list, not the hand planers list and while I may hand plane for the time being I know I am not alone when I say that someday I will build a beveler or mill. However, this is information that was trade secret just a few decades ago. Much of that information has been lost due to the secrecy. It is refreshing when one of our own is willing to share those ideas and  concepts for the benefit of all.

              So much is lost when we only measure the stations at 5 or 6 inch intervals. Like Nick pointed out in his picture, the steel bends, and because of that the ACTUAL taper is changed. Countless fine rods have been made with a block plane and a set of forms, but how many rods would Hiram Leonard have made in his time if he never broke out from hand planing? Where would our beloved sport be today if sufficient quantity of bamboo rods were not made to generate enough interest to get us to (dare I say it) glass and graphite? If you could afford a Ferrari, would you only drive it 55mph (barring speed limits and gas prices)? If we were all content with 5 inch measurements then why not make one measurement for the tip, one for the butt and call it a day? Because it does make a difference.

              Certainly if the Leonard  rod shop was starting today, CNC would be an obvious choice. Think of the endless taper possibilities. R&D becomes a mere fraction of the time in taper development. Personally I have considered modifying my planing forms for 2.5 inch centers running the entire length. It may not matter to all, but it does matter to some of us.  (Scott Bearden)

        You are right Mark, not everybody uses planing forms but the vast majority of rod makers do. Planing forms do a good job of smoothing out bumps and dips.  I will also say that the majority of makers copy published tapers and don't have a great desire to design rods from the ground up. Besides, if you don't have the original numbers of the old masters to work with anything you do from measurements of old rods is just a good guess at the original taper.  (Jerry Drake)

          A lot do use planing  forms now,  but what about the future?  As CNC machines become more commonplace, I would bet that more folks begin to use them.  And from the way the list seems to be going, more and more folks are becoming interested in taper design.  That being the case(s), why shouldn't we be more interested in improving our accuracy and precision when it comes to designing and actually making new rod tapers?  Is smoothing out the bumps and dips a real factor in taper design?  Perhaps some of those bumps and dips were inserted into the original taper for a reason.  Without the original masters around, it's kinda tough to really tell, but I would bet that in some circumstances, those bumps and dips may have been included in the taper for a reason.

          Just because "we've" always done something that way, doesn't mean there shouldn't be a reason to improve the craft and forgo the higher precision, accuracy and resolution that working out tapers to 1" or smaller stations would bring us.  (Mark Wendt)

          Plus, when you set a planing form, the forms 'bend' into each individual setting, not sudden hard changes of direction as the 'numbers' indicate.

          Kingston, Nick Form Bends

          Correct? (Nick Kingston)

            I think I said that early on too.  To get a sharp change, the form would have to be badly damaged, and probably unusable.  (Neil Savage)

          And all this to fashion a rod from an imperfect material. Age, depth of fibers, and a hundred other variables that we strive to control are lost to the whims of nature and how her grass grows. No matter the amount of work you put in, you are limited in success to replicate the "perfect" rod by numerous characteristics over which you have limited control. Your rod may actually be better than the original... but you won't know for sure until that first cast. :::sigh:::

          Just throwing my 2¢ in.  (Mike St. Clair)

            Whatchoo mean, "imperfect material?"  ;-)  (Mark Wendt)

              More like inconsistently perfect.  (Tom Kurtis)

              Kinda like my thought processes nowadays. You know... "imperfect".  (Mike St. Clair)

                Harrrumph.  I consider bamboo to be the "perfect" material!  (Mark Wendt)

              First time post from a newbie, so I am prepared to get body slammed by the experts.

              Sorry to butt in your 1" or 5" conversation, but I have a couple of newbie questions.  Does it really matter if the rod is dead on when you build it?  So you build the prefect rod in your shop, won't the measurements change as soon as the humidity changes?  No matter how you seal the blank, it will still be affected by humidity, yes?  Measure your perfect rod now and then in the winter by your favorite stream,  The prefect rod measurements will probably not be prefect anymore.  Does that make it less of a rod?

              Being an anal nerd, I understand the drive for perfection but, don't feel it can ever be truly obtained using a natural material.  I believe that is what has drawn me to Bamboo.  I feel you strive for the best but, don't become overly obsessed with reaching perfection.   See, feel and enjoy the beauty in Bamboo, as a natural material.  If you want to over engineer something, over engineer your forms.  And yes, I am an engineer during the week.

              Fire away, looks like I jumped in with both feet well over my head.  (Pete Emmel)

                As far as I'm concerned, any functional bamboo fly rod is a perfect rod.  It may not be pretty, but it's perfect.  (David Bolin)

                Well said, Pete. I've never built a bamboo rod, but have rebuilt a few. I'm just hanging out watching and trying to learn. Like learning any process or skill, you learn more when you learn to sort out the bull... I try to follow and digest all the discussion here, but depend on my gut to tell me what's doable for me.   (Chuck Pickering)

                This conversation took a left turn at some point. The original post did not discuss building the rod, only the fact that measuring in 5" increments can lose some of the character the original manufacturer built in. Accuracy, repeatability, dimensional changes due to humidity/temperature, typos, and estimating the thickness of a varnish layer can all affect the final measurement. That doesn't mean we shouldn't make an attempt to understand what the original maker built in. Can we duplicate it with a form? Probably not. Whether or not that matters is an individual choice. Personally, I would prefer to have all of the information, and then make an informed decision.

                Now, as far as my personal opinion... I have long suspected that most of the published tapers are full of errors for all the reasons listed above and then some. Case in point - the recently discussed Para 13. Somewhere along the way it lost 9" of length. What chance does the odd tenth have?  (Larry Blan)

                  I agree. That's why I'd eventually like to "design" my own range of tapers. Probably (I've already made some false starts) derived from an existing taper. When I say "derived" I mean attempting to fix some shortcomings in a published taper.   And when I say "shortcomings" I mean the way I see it. Just looking at some of the Stress Graphs taken from empirical dimensions of some classic tapers makes me ill.  As in a Roller Coaster ride. I think "That can't be what the maker intended".  Either someone mismeasured this or it had lumpy varnish or something isn't right. Maybe this is why Garrison rods are made so often.  You know Exactly what Garrison intended.  Also mathematically derived tapers like a Powell B (Linear) taper. I made a B taper 8 1/2 ft 3 piece for 5 wt and I don't really care for it.  Tips too soft.

                  I don't really believe that Leonard, Payne etc. DESIGNED their tapers on 1" increments. Were their templates "adjustable" on 1" stations ?  I think they most likely designed their taper templates, after some initial machining, WITH A FILE.  That is I think they just went at the template bar with a file to make needed changes.

                  Of course that may mean that there ARE changes that occur somewhere that would not be seen at exactly 5" intervals as most tapers are listed.  But how far off are we going to be? After all we take it as a matter of faith (sorry Harry) that any changes in dimension should be fairly gradual. So that IF there is a change somewhere between those 5" stations then it won't be more than 2 1/2" from any station and it won't be much.

                  Now I may be all wet but that's what I think. Or, as Bart Simpson said "That's my story and I'm stickin' to it."

                  I would be more than happy to have someone change my admittedly rather narrow mind by letting me cast their ORIGINAL Payne, Leonard, Dickerson etc. too see what all the 1" hoopla is about.  {:>) 

                  Most rods set up to cast at gatherings are new and thus made on 5" stations.  (Larry Swearingen)

                    You are right about most points. The Powell tip is too soft, Garrisons tapers are the DESIGN numbers not the measured ones so they are as he intended. Measures and published tapers are not consistent measured the same way and Varnish is a uncertain thing. I made a Garrison 212 with two tips; one regular and one where the station value starting at 15" went up .005 and the 20" went down by.005, did this all the way down the tip.

                    Both tips felt the same casting, I couldn't tell the difference and I did a static stress test hanging the rod on the wall and put a 6 weight standard on the tips and I could not tell the difference by eye they looked the same. I think this should go a long way toward settling the question of taper accuracy.  (Bob Norwood)

                      Garrison numbers are the DESIGN NUMBERS he wanted to publish.  There has long been debate about the accuracy of those numbers, and that the old man was keeping something to himself.  His Measured rods have diverged quite dramatically from the DESIGN NUMBERS.

                      Even the Bible is open to interpretation, and remember, his forms were bent by a workman prying on a boulder in his basement (have you read the whole book or just the tapers pages?), so how can you hope to replicate his tapers absent a bent set of forms?

                      We must all find boulders and bend our forms, and then we can be like the Amateur Master.

                      WRT a previous post, it was my understanding that the big rod companies employed engineers for R&D on tapers, reel seat design, (did they build these freehand?), process,  and stuff.  It wasn’t all figured out by Hindu mystics sitting on mountaintops (Surprise!!).  They had largish companies making these things, much like Sage, Loomis, Winston, Powell, St. Croix.  Are you postulating that these men of business, many of whom were in business for many decades, were all flying by the seat of their pants when it came to fly rod design?  Was a small time amateur the VERY FIRST Rod Maker to employ the natural sciences?

                      Damn!  You would think that if they had had access to modern methods they would have used them.  They were really Morons, weren’t they?  No wonder their businesses are gone today.  (Brian Creek)

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