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My design tool by deflection produces the output in 1 inch interval. It can draw very smooth deflection curve and as a result of calculation, I can get a very smooth taper.

Problem is how to realize this smooth taper to be planed.

Is there any tool or method which makes it possible to implement 1 inch interval control on the taper, WITHOUT using beveller or mills?     (Max Satoh)

    The simplest solution for hand planers might be to add push/pull screws to your planing forms at one inch intervals.  (Harry Boyd)

      It could be done, but I, for one, am not that dedicated that I want to make 90 adjustments for a 7'6" rod, not to mention trying to keep track of which one I was trying to do.  (Neil Savage)

        It may be really adjustment efforts to plane by 1 inch and if it's by hand.

        Shaving outside, sanding 5" interval, or designing tapers with straight intervals, might be another choice.

        Then, what is the best tool to implement 1" control? Though even mill or beveler seems to need adjustment by 1". Which machine is easiest to set 1" taper?  (Max Satoh)

      The design of most planing forms consists of two 1 inch X 1 inch steel bars. When you set dimensions at 5 inch increments you do not get a sharp bend in the form but instead a smooth curve transition from one station to the next because the bars are so stiff. So, even if you had forms with adjusting screws at 1 inch increments, I don't think you would be able to alter the taper with such precision.  If the forms had thin slots cut into the outside edges to allow easier bending then you could produce a more precise taper, but my question is: Would it be so much different from the one made at 5 inch intervals to have made a noticeable difference?  I don't think so. There are far to many other variables in making a rod that will obscure such efforts.  (Al Baldauski)

        I don't know so far how it does make difference by 1" interval from 5" interval. I just wanted to consider how to implement 1" control without spending much money. LOL

        While playing around several types of rod deflection, the resulted tapers also differ from one to another.  To realize the differences, I have to make them one by one, anyway.  If I follow the way of Garrison, I may be able to make rather straighter tapers which will fit with 5" interval Planing Form.   It is also an interesting try to make various types of deflection by changing the degrees and portions of bending more or less, by fixing the 5" station intervals as  straight as possible.

        As you advised, it may be a good way to make Planing Form from softer metal like brass bars, which may be more flexible for 1" control, and easier to make, if I need to make one.  Thank you, I take this idea.

        There may be more things to be considered on a rod for smoother transition of force such as taper, node, ferrule, etc.. All these small matters may affect the feeling of a rod action as a whole.  There are so many things to play with in the rest of my life. Rod making is really enjoyable by those matters.

        A rod deflection, I am playing now, is interesting. A deflection I mean consists of the sum of bend angles of subdivided rod sections. An entire flexure of a rod is counted as the sum of bend angles of 1" sections of the rod.  As the result, tip top tangent angle represents the whole flexure of the rod as the sum of 1" bend angles.

        Considering this reversely, for instance, 80 degrees tip top tangent angle could be resulted in various tapers which distributes the bend angles in various ways along with the entire length. If I distribute the 80 degrees evenly along with the entire length, (e.g. for 7 ft rod, 1" bend angle is 80 divided by 74" action length, each 1" section will bend 1.08 degree), the rod would flex evenly like a crescent, and the tip top tangent makes 80 degrees.  If I do it 60 or 70% of 80 degrees on tip section, the rod may become tip action type.  60 or 70% on butt, rather parabolic,  like that.  90 degree tip top tangent angle  would also result in various tapers. Various kinds of tapers, there are! by changing both of the tip top tangent angles and their distributions.

        When I get those various types of taper, I may need to control those tapers in 1".  (Max Satoh)

    I think that Luis Marden  (the late Smithsonian photographer) had a planing form with push-pull screws at one inch intervals. So it has been done.

    I think his form also had built-in micrometers for adjusting the taper. The story is that he had the Smithsonian machine shop guys make it for him.  (Jeff Schaeffer)

    It might be interesting to set up forms at 5"  intervals and then measure them at 1" intervals.  My guess is that you  might be closer to your goal than you think.  (Ed Berg)

      Yeah, it may be true.   While we believe the station interval is straight, sometimes the pressure of plane might make the depth wider between the PF stations apart from our consciousness. On the other hand, bunch of bamboo dusts between the Planing Form bars might make the depth shallower than expected very often. (Are we making various tapers by these? LOL)

      I maybe able to use 5" Planing Forms  for 1" control (consciously. LOL).

      You encouraged me very much with several ideas.  As there were several opinions given to me offlist, and for the purpose of the list, I dare to introduce those ideas as follows;

      * Use hi tech plastic or nylon for more flexible Planing Forms.

      * Use softer material for Planing Forms

      * Use thin plate for more flexible Planing Forms

      * Place shims between Planing Forms bars

      * Cut outer side of PF bars for flexure of Planing Forms

      * Put push/pull screws at 1" interval .

      My idea:

      * Shave, Sand outside of blank off after gluing.

      This is often used when we make inside out blanks where enamel side faces inside and pith side is facing outside.

      If it is just for test rod purpose, it might be forgiven to sand outside of glued blank just a bit even in normal outside out making either.

      I made a jig,  I  call  as  Para  grinder  (the  pan  of  Para  glider,  my ex-favorite fly), which will sandwich a rod blank by two pieces of sand papers and sand both sides of the blank at the same time by pushing the blank forth and back. This is also good to finalize the surface of rod blanks prior to coat.  (Max Satoh)


I have noticed for a long time that some rod programs calculate the taper to one inch spacing. Are there any makers that can actually use this information to set their forms. If so where on the taper form do you use this information?

I'm very pleased with myself if I can get the 5 inch stations to within +- one thousand. Further, many folks have said that the older rod tapers do  not seem  to hold these tolerances from rod to rod, so why should we attempt to control tapers to one inch ?  (Bob Norwood)

    There are some folks who use mills capable of being set at 1 inch or less intervals.  Other than that, being able to extrapolate numbers to account for ferrules and guides is a plus.  (Mike Shay)

    I, for one, agree with you.  If you’ve got your adjusting screws on 5 inch centers, then one inch data points are meaningless.  Even if your screws were on one inch centers you couldn’t make fine enough adjustments to make any difference unless you used extra fine screw threads. Even then, fine tuning between 5 inch centers won’t be noticeable in casting.  There are too many other variables overshadowing one-inch nuances.

    In my program, I interpolate and calculate data on one inch centers because it gives smoother graph curves.  (Al Baldauski)

    Forms cannot take advantage of 1" settings, but someone using a pattern or CNC certainly can. Of course, the dimensions that are spit out of any of the Hexy apps are just averaged across the 5" span, so they do not necessarily reflect the dimensions of the original rod, assuming we are duplicating a taper. As far as I am concerned, in many cases we are not building the older tapers. We threw away the original dimensions when the rods were measured in 5" increments in order to set our forms. Does that matter? Well, absolutely probably, or not...

    I guess I'd rather have it and not need it than need it and not have it.  (Larry Blan)

    The one inch increments can and will be used with machines, such as a CNC beveler or mill.  Or on non-CNC machines that use taper bars that are machined to the inch station.  (Mark Wendt)

      As much as I hate to admit it, Mark's right...(belch) nudder beer please?

      If one uses a program such as Max's, one inch measurements become a lot of fun!

      When you look at a lot of stress curves, one HAS to wonder if some of those weird spikes and dips were intentional. Hard to straighten them out (if that's one's intention) on anything but a mill with one inch or less capability.

      I've watched Jerry's machine work. Cast a bunch of his rods. VERY repeatable!

      I wish I had one.  (Mike Shay)

        Indeed.  Looking at some of the old Payne taper charts that Hal Bacon graciously showed us a few years back at the Catskill and Grayrock gatherings, all were done in 1" increments.

        One a these days I gotta send you one of my homebrews Mr Shay.  You'll be spoilt for life...  (Mark Wendt)

          Just a couple  of short questions:

          As I understand it, towards the end, Jim Payne was finishing rods with a plane and forms, because the mill was too worn to be rebuilt to the old accuracy.  Doesn't that mean he ended up with a rod essentially built on 5" (or 6") stations?  Weren't the bumps and wiggles developed over the years of creating and fine tuning tapers for his mill compromised (at least where they didn't coincide with a station)? Did it make a difference?

          Are tapers based on bumps and wiggles better than tapers based on fair curves and straight lines (probably a matter of taste, at least to some extent.)?

          Are we splitting the proverbial hair?  (Roland Cote)

            Maybe so.  I hadn't heard about the mill wearing out.  That would be a good question to ask Hal Bacon.  Hal, if I remember correctly, has repro'd either the Payne or Leonard mill.  The CNC mill that I'm making is based on those historical designs.  (Mark Wendt)

              I saw Hal's presentation at the Catskill gathering I remember that he had reproduced the Leonard machine which was a beveler, not a mill. It used two opposed saw blades at 60 degrees and could cut very fine tips. The rest of the details are hazy but as I remember the blades did not cut all the way through the strips and that the "flashing" was removed by hand.

              I don't think that he used CNC because he was reproducing Leonard tapers from the original steel templates or copies of them.  (Doug Easton)

                Yep, he was using the Payne and Leonard taper bars, I believe.  It's my machine (if I ever get the damn thing done) that's CNC, and is based on both  the Leonard and Payne bevelers.  (Mark Wendt)

                Hal is using the original Halstead beveler. Hal bought it from B. Schoff some time after selling the Payne Co. to REC. The Payne beveler went with the company to REC and then to Dave Holloman. Hal has rebuilt and modernized it. Saw blades were 60 degrees apart with 2 thou. between the blade tips. The cut strips came out of the beveler in one piece and were smacked on a table to separate the finished strip from the chaff. Apexes were removed before glue up. I think I got all that right  (Dennis Higham)

            I'm not an engineer, but when you ask: "are tapers based on bumps and wiggles better than tapers based on fair curves and straight lines?" it seems to me that the answer must be "no." Personal casting ability tells the tale in the end -- a great eradicator of all theory -- but simply in terms of  design potential,  the answer is still "no."

            "Bumps and wiggles" have been a standard in the industry for generations, but I'd be willing to bet that most of these evolved haphazardly rather than through carefully controlled, design choices. How can the flexing energy in a rod  (not static deflection stresses, now, but the flow of linear wave forms) move smoothly and efficiently through a series of bumps and wiggles? Why seek to replicate areas of inefficiency when there's no need?

            It seems to me that the most efficient designs would be those whose tapers incorporate a series of fair curves. "Splitting the proverbial hair?"  Sure, but that's what all rod design does. We're always talking about matters of a few thousandths of an inch here and there.

            Can the average caster tell the difference? Well, that's for each caster to say, but this is different matter. We've only been talking about design potential.  (Bill Harms)

              Not long ago, there was a rather lengthy thread on this list regarding tip vibration and its affect on loop form and line waves and the resulting loss of casting efficiency.  Late in the discussion Tom Smithwick reported the superior performance of Vince's rod in this area.  To me, this speaks volumes about the relative merits of fair curves as opposed to bumps, etc. (Roland Cote)

                Well, yes, it's true. Tip-bounce is always caused by a taper that's "out of control" through its last 15 inches or so. A fair curve through this area (and out to the tip-top) is crucial to translate the last bits of flexed energy into line-speed. Conversely, if you see waves going out through the line, it's because the upper portion of the tip has been compromised with bumps and wiggles, and the tip simply isn't up to doing its job.

                Anything that bounces up and down guarantees sacrifices in linear drive. Some casters may learn to control tip-bounce to an extent, but why should one need to learn this? The solution is not to learn how to compensate, nor is it a matter of building a heavier tip. It's a matter of maximizing the rod's efficiency in the first place by managing the shape of the taper.

                And the same holds true through the other areas of a rod as well -- even though a wavy, forward cast may not  show up as final evidence. There are many good ways to manage fair curves (even with "compound" tapers), but the series of bumps and wiggles we so often see is definitely not one of them.  (Bill Harms)

              You may not actually be an engineer by trade but you can clearly think like one!  (Robin Haywood)

                I agree with you on all points (fair curves from a design point are ideal, hinges in non-specialty rods seem like a bad idea, "bumps & wiggles" were probably due to inaccuracies originally, but get propagated as "must have been designed that way")  (Chris Obuchowski)

    I think the 1" measurements are only practical for those (Foster & Bogart) using the CNC milling machines. Most everyone else using milling machines are set up for 3" increments. I don't think the 1" measurements can be translated to the planing form.  (Will Price)

    Some my use the information to set forms for tapers they have on 6" intervals by entering the taper on 6" intervals, calculating and them use the 5" intervals to set the forms.

    Another  use may be for forms setup when using step-down ferrules and the ferrule falls between 5" stations.  (Don Schneider)

      I think the people that get the most advantage from 1" intervals are those who use a milling machine or Morgan Hand Mill. I suppose they can use 5" or 6" intervals, but they are not hampered by adjusting bolts for every so many inches. I think mic'ing every inch gives a better picture of the overall taper, but is unnecessary when using planing forms.  (Scott Bearden)

      It seems to me that all taper data until recently has  been derived by measuring on 5 or 6 inch centers.  So any data reported on 1 inch centers has to be interpolated.  The CNC machines should take 5 inch information and interpolate it and arrive at the same numbers.  The problem with a CNC using interpolated data or taking 5 inch data and doing its own interpolation is that it won’t produce the same taper as a set of steel forms.  Steel forms, when adjusted, provide a “fair” curve between stations because they don’t bend in a sharp angle at each station, it’s a gentle bend.  Unless the CNC software compensates for the gentle bend when it interpolates, it will actually mill a series of straight sections with sharp transitions at the 5 inch centers.  (Al Baldauski)

        I use wooden forms and have found the bend to be quite different depending on how you adjust them. I start at the narrow (tip end) of the section with the forms closed, loosen the "close bolts", then push open with the "push bolts". The reason for this, I was building a 3/2 and broke a spline, I finished the 11 and then went back to a spare strip, I started adjusting the taper at the wide end of the forms and measured everything, set the depths, was on the dimensions on the 5" intervals, but the strip never fit in with the other five, hence the 3/1 7.5' 4 wt rod I now have.  (Pete Van Schaack)

        I didn’t phrase my last sentence correctly.

        The CNC will mill a series of straight TAPERS with sharp transitions at the 5 inch centers.

        And “sharp” is a relative term.  It will be “sharp” compared to the steel form but probably unnoticeable.  I think this is all “gilding the lily” again.  (Al Baldauski)

        When someone creates a new taper from scratch, they seem to do it at 5 inch centers.

        But when someone measures an existing rod, at least one with the hardware in place, usually there are guides & ferrules in the way, so they get some measurements at the 5 inch points and some at other nearby spots, and maybe one each side of the ferrules and the start of any swell. The online Hexrod, and I assume the other rod design programs, uses all the measured points to interpolate to 1 inch stations and then report either the 5 or 1 inch stations as requested. So if a rod is 0.132 at 27 inches and that is put into Hexrod, that value won't be lost or smoothed away; it will show 0.132 at 27 inches. But if its 0.133 at 27.75 inches, that value will be used to interpolate to the whole inch and the exact measurement at 27.75 won't  be retained.   (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive)

          I use wooden forms and have found the bend to be quite different depending on how you adjust them. I start at the narrow (tip end) of the section with the forms closed, loosen the "close bolts", then push open with the "push bolts". The reason for this, I was building a 3/2 and broke a spline, I finished the 11 and then went back to a spare strip, I started adjusting the taper at the wide end of the forms and measured everything, set the depths, was on the dimensions on the 5" intervals, but the strip never fit in with the other five, hence the 3/1 7.5' 4 wt rod I now have.  (Pete Van Schaack)

          I didn’t phrase my last sentence correctly.

          The CNC will mill a series of straight TAPERS with sharp transitions at the 5 inch centers.

          And “sharp” is a relative term.  It will be “sharp” compared to the steel form but probably unnoticeable.  I think this is all “gilding the lily” again.  (Al Baldauski)

          When someone creates a new taper from scratch, they seem to do it at 5 inch centers.

          But when someone measures an existing rod, at least one with the hardware in place, usually there are guides & ferrules in the way, so they get some measurements at the 5 inch points and some at other nearby spots, and maybe one each side of the ferrules and the start of any swell. The online Hexrod, and I assume the other rod design programs, uses all the measured points to interpolate to 1 inch stations and then report either the 5 or 1 inch stations as requested. So if a rod is 0.132 at 27 inches and that is put into Hexrod, that value won't be lost or smoothed away; it will show 0.132 at 27 inches. But if its 0.133 at 27.75 inches, that value will be used to interpolate to the whole inch and the exact measurement at 27.75 won't  be retained.   (Frank Stetzer, Hexrod, Taper Archive, Rodmakers Archive)

          And a further complication which probably introduces the most error in reported numbers is the "assumption" for varnish.  (Al Baldauski)

            I think the advantage of these programs is that, if for some reason, a station is missing or can't be measured, the 1" increments let you estimate what it should be.  It also lets you graph the rod and spot anomalies. For instance, the Payne 201 we were discussing a week ago had step down ferrules.  This wasn't noted in one of the measurements, but it shows up in the liner graph as a hump. 

            Since rodbuilding straddles the line between art and craft, it is not surprising that we sometimes lay too much emphasis on the precision of the craft, to the neglect of the art.  I sometimes wonder if the final scrapping shouldn't be done after a "test drive" of the blank, peeling off a half a thou' here or there to smooth out the action.  (Paul Gruver)

        Chris O works with a MHM. . .on five inch centers.

        Chris Bogart, and Jerry Foster, both have the CNC mills.

        As to whether one inch centers make a difference.  (Chris Obuchowski)

          The correct answer is "how many points does it take to define a STRAIGHT LINE" SIX or TWO? I'm sorry but we have all been wasting time and paper. 5" station to station settings gives a straight line 1" settings gives a STRAIGHT LINE. Check it out !!  (Bob Norwood)

            It may start out as a longer straight line, but when you draw it up in a CAD program, and use the SPline command, it smoothens the straight lines into many short straight lines, and situates the points around an arc..  Then you feed it into a CAM program, or do some fancy fat-finger typing in the G-Code file, and voila! you have smooth transitions between the station.  After all, a curve is nothing more that a series of points in an arc, and between those series of points is a straight line.  The trick is to make that  straight line as short as possible.  (Mark Wendt)

              Hmmmm. . . you've got me wondering now.

              Does the CNC mill effectively mill a bunch of short straight sections with obtuse angles between them (at the inch increments), or does it produce a "fair curve" the way a planing form or MHM does (both effectively steel battens with smooth curves and no angles)?  (Chris Obuchowski)

                It depends...  ;-)  Servo powered machines can have smoother cuts than a stepper powered system, due to the way the servo operates versus the way a stepper motor operates.  But, a good stepper motor can "micro-step" in effect making each of those movements quite small.  A servo doesn't use steps to make it's movement, and it's driver is much different than a stepper driver.  That being said, there's lotsa tricks available in the CNC controller software to smoothen things out, along with how the movement of either the stepper or servo is done.  Under a microscope, you'll probably see straight lines, but they'll be so small they probably won't matter.  Remember, a curve is nothing more than a lot of teeny tiny straight lines going around an arc.  At least in the digital world.  Servos, while digital, replicate analog movements better than steppers, but steppers still do a pretty darn good job of it.  (Mark Wendt)

                Short little straight lines. It will jump at the inch marks but the jumps are VERY short. I didn't notice them after glue up if that's what you're after? Not really noticeable on a per strip basis either.  (Mike Shay)

                Unless I am missing something, all of the numbers that I see from one inch rod programs are simple derived by taking the difference between 5 inch stations an dividing by 5 to get the 1 inch values, which to me is a straight line, station to station, using either one or five inch points. For those of us that still use planning forms, five inch values are all we need, and truthfully I have difficulty setting those to a one thousandth tolerance. The only place where you might think one inch stations would help is in the first 15 inches from the tip because some programs show a rather large spike in the stress curve at these points. The spikes are not from the taper, they are caused because the data used in the program has been entered incorrectly.

                The spikes are not actually there.

                Look at Franks "HEXROD ONLINE" and check out the detailed taper numbers, you will see that there are no large increases, However there is a small stress value increase between the 5" and 10" stations, but these values are nothing to be concerned about.

                Again you only need two points to define a straight line between five inch stations unless you need them to find the value at a 5 inch station and it's under a guide as Paul and Judy pointed out.  (Bob Norwood)

                  It all depends on how you create the taper.  If I tell RodDNA I'm working on 1" stations, it'll save it in 1" stations.  If I have a CNC machine (which is in construction) I would be nuts to use 5" stations and not take advantage of the precision and accuracy of using 1" or less stations.  Take a look at one of the "real" Payne tapers, and I guarantee you can't set your planing form to match the exact taper.  With the CNC machine, I can.  We're talking apples and oranges though.  Since you're using a planing form that is set on 5" stations, the 1" or less distance between stations won't make a whit of difference for you.  But for folks that use a machine, or have some kind of set up where it's less than 5" centers, this comes into play.

                  The 1" station method can come in real hand if you're mic'ing a rod, and saving the settings as 1" stations.  You might miss a couple or three stations due to ferrules, wraps or guides.  those missed stations can then be interpolated using the software, and I betcha the taper would more accurately be determined than doing it every 5" or so.  (Mark Wendt)

                    I am a hand planer and will remain one always, I guess;  not so much out of being a Luddite, but because I build as a hobby, build a few, sell a few, and I don't aspire to any great volume of production, nor to any speed in building.

                    I am currently playing with a Morgan Mill that has been bought by a friend, and while it is a nice machine, I don't want one, as I can't really see what benefit it gives a hobby builder of hexagonal rods except accuracy and repeatability, and I am not too bad on those parameters with my forms as it is.

                    But Blind Freddie could see the possibilities of a CNC high speed mill set up on 1" centers, and while I would never want to own one (?) I can still drool a bit over the capacity of the thing to produce micro-tuned strips, from which, presumably, sections and rods of precision could be built, and which could have adjustments and design improvements incorporated that are just not possible with my 1" square bars and 5" push/pull screws.

                    One practical question, though - when you mike a Payne 101 built on, say, Jim Payne's numbers, on a 5" center set of bars, and then mike a Payne 101 made on a CNC, also to Payne's original set of numbers, do the measurements at each 1" station in fact vary much from the numbers that would be produced by following a "fair curve" on a set of bars?

                    You see, I am assuming that you have done this!  Or that somebody has done it....

                    Jays, I wish I was about 20 years younger - I'd be right into this CNC mill stuff like a rat up a drain!  (Peter McKean)

                      I would assume that the measurements taken at 5' stations wouldn't deviate much, if at all on the two rods.  Since the "hand planed" rod was set up and planed at 5" stations, whatever dimension was set at the 5" station should be there on the final rod, doubled of course, and taking into account the thickness of the glue.  A rod that was made by a CNC machine, as long as the same dimensions were used at the 5" locations (as well as the other dimensions at the 1" stations) should, indeed, have the same dimensions at the 5" stations as the rod mad in a planing form with 5" stations.  Rods that were designed on 5" stations will see little to no difference in the taper's performance when cut on a CNC machine or hand planed.  But, rods that were designed on 1" stations, and cut on a CNC machine versus a planing form made rod with 5" stations might, and probably would, have subtle differences.  If you look at the original Payne taper, designed on 1" stations, there really is no way that you could make an exact copy of the rod using 5" stations.  you can come close, but like I said before, there would be subtle differences.  (Mark Wendt)

                      I have read with a lot of interest the conversation on the taper control and CNC mills.  But now I am curious about the CNC mills.  Who produce CNC mills in USA?  How much is the price of a mill? For now I know only the name of JW Rods. Others?  (Marco Giardina)

                        A straight line is a straight line. Are you saying that rodna gives values other than a straight line between 5 " stations ?  (Bob Norwood)

                          RodDNA gives you the choice of how you can enter your dimensions.  If I enter the dimensions on 1" stations, I will have different dimensional numbers at those same stations than if I had just entered the dimensions at 5" stations.  (Mark Wendt)

                            If you ENTER numbers on 1” centers then RodDNA retains those numbers entered.  If you enter numbers on 5” centers then look in the detail screen which show values on 1” center, you’ll find those 1” data are linearly interpolated from the 5” data.  (Al Baldauski)

                              Yeah, wut he said...  That's what I was trying to say.  Dammit, must not have had the requisite amount of caffeine today.  That's two doh!'s on me today, both caught by Al.  (Mark Wendt)

                              That is how I implemented it.  If you think there is a better way to implement the values that would more closely reflect the "fair curve" of a planing form as I believe you mentioned previously, I would be interested in implementing it vs. or in addition to the existing linear interpolation.

                              For me, since I make many different models, a computer controlled beveler is interesting mainly from a setup perspective.  i.e. very fast setup.

                              I advertise handcrafted rods, so I am not really interested in having any machine pump out strips with presumably 100% accuracy, as I believe a few swipes of the hand plane will remove any chatter made by the cutters, no matter how good the cutters are believed to be.  (Larry Tusoni)

                                My personal opinion is that implementing a “fair curve” algorithm is “splitting hairs”.  In most tapers the CHANGE in slope between stations is so small that it just doesn’t matter!  The CNC machines bring repeatability to the machining of rod strips but I doubt that they will result in superior rods.  There are too many other variables affecting overall performance.  (Al Baldauski)

                                  I guess that for the folks that just can't stop being more and more anal, 1" intervals  make sense. But, hey, as long as smaller is better, why not 1/2" intervals? Do these guys shudder at the thought that rodmakers of old used empirical data and seat of the pants   trial   and   error decision-making? Maybe Mr. Garrison put a monkey on our collective back with his engineer's compulsions.

                                  I am willing to speculate that some of those famous old makers would laugh at these compulsions. They had livings to make. Don't forget, lots of rod tapers were measured in 64ths at 6" intervals and some of the rods were pretty good.

                                  Our little universe of fly fishing and bamboo rodmaking has so many differences in fishing conditions, line weights, casting distance, fly weights and size, glues, natural cane variations, node staggering, measuring variables, wrappings, heat treating, varnish variables, casting abilities, and probably lots more, that it boggles my slightly scientific mind that we actually come up with rods that are fine fishing instruments. It's as though we are we looking for watchmakers' machining accuracy to make a hammer or pair of pliers.  (Steve Weiss, graduate of the KISS Institute of Bamboo Rodmaking)

                                    Measure it with a micrometer, mark it with a crayon, and cut it with an axe.  (Larry Blan)

                                      That about says it all!!!  (Bob Norwood)

                                      You callin' alla them Stanley planes you got bad names?  Tch, tch...  (Mark Wendt)

                                      I'd like to build a rod that is 1/5 of a stone and 4-1/3 cubits long... does anyone know of a good taper?  (Mike St. Clair)

                                        Pool cue?  (Peter McKean)

                                        We'll have to decipher the hieroglyphics, but I understand there's one hell of a good Nile River catfish taper on the walls of the pyramid of King Tut.   (Mark Wendt)

                                    Over the year I have suspiciously looked at all the different tapers from some to the well known makers. There are several different versions of the same model or are there? Or did they build the same taper and just not hit the numbers due to worn machinery or forgotten numbers? Some actually came out better than others or did they, is it just what feels best to the caster? Again there are many ways to skin a cat and that is what makes this craft so much fun. There are also many styles of rods being built and there is the perfect rod out there for everyone.

                                    I personally think there is quite a bit of MOJO or black magic required to make the perfect rod. Can't get that with a CNC or forms either. See those 10 fingers in front of you? Those are your best tools.  (Joe Arguello)

                                      I only have 8 fingers so I guess that perfect rod may just be out of my grasp.

                                      But I do have two opposable thumbs.  (Greg Reeves)

                                      Yep, and they're typing this message to you, and will eventually be typing the      black     magic G-Code...  ;-)  (Mark Wendt)

                                      After working with wood for 40 years I can say with confidence that no two pieces of wood are exactly the same. I pretty sure the same is true with bamboo. Soooooooo when we say we hit the numbers exactly, or even close, on a blank, how do we know those were the right numbers for that particular  piece of cane? I think that's where some of the mojo comes in. Not being exact all the time may be a good thing. Then again I may be all wet.  (Tom Kurtis)

                                        And to complicate things, Tom Morgan, a number of years ago, did some testing where he measured the same strip at different times of year, in different humidity, and if I'm remembering correctly got numbers that varied .003-.005" for the same section.

                                        So who knows what the ambient humidity was when that "classic rod" was cut or measured?  (Chris Obuchowski)

    I don't think anyone mentioned that "template" based bevelers/mills have the potential for much finer resolution than the traditional 5" or 6" station settings.  And I believe that at least the Leonard tapers were designed with much finer resolution than 5" intervals, probably 1" resolution or better.

    If you use RodDNA, you can enter your model taper values at 1" ~ 12" station increments.  You can then either change the "Station Increment" to whatever you desire (normally 5") and they will be converted automatically.  Also, if you don't specify a station value it will automatically calculate it.

    Alternatively, you can keep the taper values at which ever station increment you desire, and you can simply print a planing report at the station increment of your planing forms (typically 5 or 6 inches) or at 1" increments for a mill, etc.  You set the planing form station increment in the program options.

    For example, most of my taper are specified on 6" intervals, so I simply keep them as they are, and print a planing report at 5" intervals if I hand plane the strips.  These 6" tapers are also measured from the butt  to the tip (backwards than we do it today), so I have a routine that inverts them.  If this is of interest, I will add it to the next release.  (Larry Tusoni)

      "Potential" is right.   But with what  precision  was the  template made?? Chances are the "oldies" were rough milled and hand filed and that CAN get pretty good depending on who's running the file!  Once complete it, it should compare favorably with CNC for repeatability.  (Al Baldauski)

        Good question.  I know the Leonard templates were quite impressive, made of metal and precisely tapered.  I don't know what process they used to taper them, but the results were very impressive as they, presumably, resulted in very fine tips.  (Larry Tusoni)

          Well, however "precisely" the templates may have been tapered, the resulting rods vary all over the place! I wonder if anyone owns a Leonard rod that corresponds exactly to its template -- or if any two examples of a given model mic-out the same.

          Maybe I just need a new prescription.  (Bill Harms)

            Maybe I should have said the template  COULD BE not should be as repeatable as the CNC.  Just as with any machine, it's only as good as its operator!  (Al Baldauski)

            All I know is that the flat to flat dimensions on the Leonard rods I own and have repaired were usually within +/- .001.  How they achieved that is anyone's guess.  And some of the tips were as fine as .024"! That would imply some hand-planing to me, unless their mill(s) could actually saw the finish strips that finely.  Seems unlikely to me.

            I don't have multiple versions of the same Leonard models so I can't speak to consistency within them.  (Larry Tusoni)

      The particular CNC mill that I, and a few others have, is as accurate as the enamel has been treated. If it flat end to end, and across the flat it will cut strips more accurately than I can measure. Is it almost impossible to get the enamel perfect, you bet. So I put up with strips that have a maximum deviation of .001 on occasion. The repeatability factor of the machine is 100%. The resultant strips are subject to the above.

      The other facet of the mill beside the holddown technology is the cutter. I am being led to understand that JW may be selling his custom made cutting bits. These are the ones with the micro-carbide inserts.

      There are many good taper programs out there. RodDNA and Bob Norwood’s come to mind as well as a number of freebies. The only one of any significant difference is Max's. Beside the fact that all of his math is in a dynamic mode. One of his tools converts straight line input to bezier curves. Another of his tools produces usable output for a CNC mill directly. (G Code).

      The other issue is that a decent CNC mill is capable of 20,000 steps per " along the X axis and 100,000 s/" on the  Z. This  kind  of  resolution  in/in minimizes  any noticeable  angular transitions. Plus a router running at 28,000 rpm.

      If you want to know about CNC bamboo milling, just ask, I will answer you as honestly as I can.  However,  I know it is more fun to speculate.

      If you don't like the word "clone" perhaps we should call them "Replicas". But that also infers exactness.  (Jerry Foster)


I should have included 7 foot 9 inch rods in the rod length poll.  I don't know what to make of it, but we seem to be creatures of habit.  Most of us make 7’, 7 1/2’ and 8’ bamboo rods.  That's apparent from the poll and a compilation of tapers from RodDNA.  Some have argued that tapers should be measured in one inch increments.  So why aren't we making a bunch of tapers with lengths at every one inch interval between 7ft and 8ft?  If the taper has a significant impact on the performance of the rod in one inch increments, should the length be equally significant?  Just thinking out loud...  (David Bolin)

    Arguably Garrisons most popular taper is probably his 7'9" 5 wt. The best Horrocks-Ibbotson that I ever owned was definitely the Tonka Queen, here again, 7'9". A lot of makers have a 7'9" taper in their offerings. I can't see the reason for the 1" increments unless one has a CNC mill. As far as I'm aware that is the only mill capable of 1" steps. Payne, Ron Kusse among many others had/have mills that operated on 3" steps. Hence the the flat foot measurement, the foot/3" models PHY Midge as an example, the popular foot/6" (71/2'), the foot/9" Tonka Queen, Payne Parabolic 7'9" (he also had a 7'1" parabolic but that doesn't fit the profile LOL). That to me would make more sense than the 1" measurements. But the vast majority of rods are made in planing forms that work on the 5" steps. We rodmakers aren't happy unless things are harder or more complicated than they need to be <G>.  (Will Price)

      What about one of my favorite rods, the PHY Driggs River Special?  It is 7'-2" long.  Let's face it, even foot and half foot measurements don't fit with 5" increments anyway.  (Hal Manas)

        Good point Hal. I think that a lot of the "odd" length tapers happened because the maker cut at different points after using the same taper bar. Of course that is purely speculation on my part. I do believe that I read on another site that Rob Smith was saying that Walt Carpenter owns original taper bars from one of the early makers and that the bar was marked in different places with notations for different rod models.

        I guess some things are always going to remain a mystery.  (Will Price)

          Gary Howells did this; he'd plane out long sections and then cut them to length, and thickness, depending on what he wanted (5 versus 6 weight, 7 footer versus 8 footer, etc.)

          Works well when you use straight tapers.  (Chris Obuchowski)

        I too, never understood the 5" increment thing. It like someone was mixing ideas together when all the tapers are in roughly 3-6 inch increments. I'm real surprised that the 7'9" length was not in the poll. To me its the ideal length, as far as versatility goes. But, then what do I know, I'm just a lurker with not enough time to make rods these days. I'll go back to my corner and watch. Good night.  (Bill Walters)

        Hey guys.  I've never been clear about why or why not planing on forms tapered in 5" increments would be inferior to tapers made to smaller increments when making rods of 'in-between' lengths; e.g., the 7ft 9 in length already discussed.  In a straight taper, it's all the same.  Think that's a given.  I guess the problem only enters when you start compounding the taper, but then if these weak or strong stress points are placed properly and the areas between are basically straight line from there to the tip or the next change, what's the real difference?  Seems to me these things would be subtle enough not to be felt in actual casting/fishing.  What do you guys think?  Enlighten me.  (Bob Brockett)

          One of the things I've noticed is that when you set planing forms you don't get a straight line from one station to the next, the settings at the stations above and below the space between 2 stations will affect the curve there. Planing forms have a subtlety all their own that's not reproducible by milling machines with patterns made to 1" increments <g>! Again we find ourselves trying to reproduce what others have done. It's always been somewhat obvious that this is not totally possible, so make your rods however you can or want and enjoy them each for what they are, an individual with qualities all it's own.  (John Channer)

            In other words, if you want as close to an exact copy of something as possible, you'd better use the same form or milling machine or whatever the original was made on.  Guess   that   makes   most   sense  of   all.   More coffee...thanks John!  (Bob Brockett)

          I am convinced there would be no discernible difference. Al Baldauski raised an interesting question a while back about a rod design where the taper zig-zags up and down over alternating stations vs. one that runs smoothly through the stations averaging out the up and downs. Both rods result in exactly the same deflection curve.

          I am still to be convinced by the often mentioned argument that some tapers (e.g EC Powell’s saw cut tapers) can’t be reproduced on forms with 5” stations. They obviously couldn’t be ‘micrometrically ‘ identical but I seriously doubt anyone could determine the difference when casting/fishing them.

          I would be very surprised if there is any rod that can‘t be made on a form with 5” stations near enough to make absolutely no difference to one made on 1” stations.  (Steve Dugmore)

            Thanks for making clear language of  what was sloshing around in the back of my foggy mind.  This about Al Baldauski and the zig-zagging taper interests me.  I'll have to look back and see if I can find that.  I was thinking after I posted that last that I was probably extreme in my conclusion that you'd have to use the same machinery, for lack of a better, in order to perfectly reproduce an original.  I suppose if you wanted an actual new Rembrandt oil, you'd have to invent another Rembrandt first.  Still, it's not the same thing (for a number or reasons), is it?  These are natural materials.  Every culm is different.  Every maker is different.  And so the maker's tools and methods.  I guess the most extreme thing you could say is that every rod is an original in some aspects, not that the originator of any taper should be overlooked in the process.  Or is that extreme?  Don't know.  Well, I've succeeded in being made clear on something only to muck it up again.  Such is life.  But, like you say, none of this probably makes any real difference.  Thanks Steve!  (Bob Brockett)

              I think Bob Norwood is the one who raised the question.  I used his numbers in my deflection program to show that the zigzags average out so there is no deflection difference re: a “straight” taper.

              I don’t have his numbers anymore but I might be able to mock something up to show you.  (Al Baldauski)

                No, no, that's fine Al.  Sure you have better things to do.  I do understand what you're getting at here and it's something I (no mathematician, God knows) suspected in a general, intuitive way (which, when you can't get the math, is what guys like myself are stuck with!).  Someone,  can't recall just who or where, showed how most of these quick 'hinges' people sometimes throw into tapers really don't work because they're only inserted for a single station or so.  To influence the overall action, it has to be graduated over several stations; more a  compounded area than a point.  That much does make sense to me, although you'd actually know about this empirically, where I'm just guessing.  Thanks Al!  (Bob Brockett)

                  Al is correct, Awhile ago I asked the list if they thought there would be any differences between two tips on the same butt, one built as a regular Garrison and one with the tip made to zig zag by .005 at each consecutive station. The answers I got ranged from; they would feel the same to you will feel every hill and valley. Some said the forms wouldn't  take that kind of twisting. I used a Garrison 212 that I had and made the second zig zag tip with a change of +- .005 between stations. The static deflection test showed no differences that I could see after I drew the tip of each on the wall they deflected the same distance also.. The flex test that I did by holding the two tip ferrules and then forcing the tips against a table showed no difference either, at least none that I could tell. I took the rod to SRG 2008 and those few who cast the two could no really feel any major differences either.

                  I also made three tips for a rod and changed the diameter by adding .005 for each 5 inch station. These tips did show a difference in all the tests that I ran for the zig zag above. There was a difference in the way they cast also, but not as much as one might think.

                  My conclusion was that it takes quite significant changes over a length of more than 5 inches to change the action of Bamboo rods and that differences of one or two thousands at any station makes little or no difference in rod action. Now realize that I am not the worlds greatest caster and maybe there were actual differences that I couldn't feel, but, these are the results that I found.  (Bob Norwood)

                    Thanks Bob!  If this isn't food for thought, I don't know food.  I guess each individual caster knows what's meant by 'tip heavy,' and stress graphs will show these things well enough, but so much of this is feel and pretty subjective in the end.  Personally, I prefer things that way.  Nothing more boring than a purely mechanical universe.  Apologies to Cartesians  everywhere.  (Bob Brockett)

            Do you know the real reason that I build hexagonal section rods on 5" centers ?

            It is because I have a set of forms with a 60 degree groove, and the stations set on 5" centers, that's why!

            I build about 20 rods a year these days, I really enjoy the building process, and they are excellent performers with which my customers seem very well pleased.  I take as much care in the building of these pieces as I possibly can, and I will replace either strips or sections for the tiniest imaginable flaws during building. All in all I am very happy with the finished product, though I do try very hard not to let that state of mind slide into rank complacency!

            I have enough procedural difficulties such as getting the strips glued without visible glue lines, achieving a flawless varnish finish and getting the  bloody things straight that I really don't have time to worry much about whether or not I could be doing a marginally better  job with 1" or 2" or 3" centers, nor about whether or not I am exactly reproducing a rod I built sometime last year for somebody  else.

            Should I decide that I needed to concern myself with this stuff, I would have to start trialing different forms, at which point I would become more a form builder than a rod maker.  I certainly don't have the time, or the resources, to try to be both.

            Quadrates, I must confess, could come to tempt me one day...........  (Peter McKean)

              Unless you are going to use a machine to cut the rod on 1", 2" or 3" centers, there's no reason to even consider it.  Not only would it be a pain in the arse to set, it would take forever to set 96 stations and a few odd ones for an 8' rod on 1" centers.  (Mark Wendt)

    Time for me to step in and be the devil's advocate, again.  Who cares if it is 1" vs 5" stations?  We are working with a natural fiber, not building micro processors.  Bamboo by the way, is classified as a grass and not a wood.  Anyway, with all the variables finish, humidity, blah, blah, blah...we will never be able to match a past rod 100%.

    Again, I feel we are over engineering a grass.  I have never met a Bamboo rod I didn't like.  You just need to listen to what the rod is telling you when you cast it.  I have seen the same thing in the Nuclear industry over the years.  Example:  With all the fancy electronics we have we are able to get tighter calibration tolerances.  Like that helps with old electo-mechanical relays.  You can only take things as far,  before you are wasting your time.

    JMHO, which come to think of it, doesn't mean all that much to me either.  Now, I have to go mow the grass.  I mean plane some bamboo.  (Pete Emmel)


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