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I'm quite interested in the taper designs of EC Powell, but I just can't seem to to get info on them. Can anyone provide an overview of his A, B, and C taper formulations? I guess the A taper was the dry fly taper, and the C taper was the slower taper? From the archives I was able find that the B taper was his straight taper and had a slope between 0.008 and 0.009 inches per 6"... is this correct? And that his hollow built section thickness was 0.072 inches? Also, I would like to know about any steelhead rods he made in the 8.5 length for a 7 weight, any information on this? (Kyle Druey) I wrote an explanation of EC Powell tapers in issue #54 of The Planing Form. If you send me your snail mail address I can copy it and send it to you as long as you are not in a hurry. I'm going fishing. You are generally correct in your assumptions in your e-mail. The B9 was his most popular taper. (Ed Hartzell)
I have a question. I ran the stresses for an EC Powell a, b, and c taper. When I was reading his pamphlet he said the "a" was tip flex, butt resistant, I became confused. the "a" actually has the weaker butt of the 3. If that's true then the length of the hump at the tip must show slowness in the tip section and the relationship to the butt must make it feel that way. do you find his evaluation valid for you? they do make beautiful stress curves. The math. that’s why I believe the stress curves are a valid measurement tool. (Jerry Foster) EC Powell described A, B, and C tapers. B is a linear taper. A has a fractional rise added at each station to generate a basically exponentially increasing slope. C has fractional decrease subtracted at each station additively to generate an exponentially decreasing slope. The fraction was in ten thousandths, .000X; I've heard it described the most common was .0002 to .0004. You add or subtract say .0002 for each station (btw, he used 6" stations, not 5") For an A taper, if the slope is .013 from 0 to 5", it's .013+.0002 from 5 to 10", .013+.0004 from 10 to 15", .013+.0006 from 15 to 20" etc. For C tapers, subtract. He also often mixed tips and butts, such as a B tip with an A butt, or a C tip with a B butt. Using his formula, an A taper would have a softer tip and a stiffer butt when compared to a B (Linear taper). (Chris Obuchowski)
For some time I've been interested in the rods made by Edwin Powell and the other makers that followed him (Walt P., Maslan, etc.). I've researched EC's tapers and believe I have a full understanding of the A, B, and C tapers. The next rod I'd like to build is a B9 taper, but I'm unsure where to START the rod, dimension wise. Is there a rule of thumb as to tip dimension for a certain rod length and line weight? I recall that Tom Smithwick and Bob Maulucci played with straight tapers at various points. You guys have any insight? Another way to look at this is through Hexrod. I've used the online Hexrod program to develop straight B9 tapers. Following the Garrison (?) thinking, I tweaked the tapers until the tip stresses were under 200,000. Would this work? Should I be using a different stress value to get a true EC style rod? When I did it like this, I ended up with some pretty fine tips (eg. 8' #5 B9 - tip @ .065"). Does that seem right? (Bill Benham) Chris Carlin made a nice little Powell B Taper calculator you can find and download here. (Mike Shay) Yep, I developed a spreadsheet similar to this, except mine will compute ferrule sizes, form settings for tip/mid/butt individually and works for a 2 or 3 piece rods. HOWEVER, both mine and Chris's need to have the starting tip dimension supplied. Allow me to respectfully reiterate - I know how to figure out what the taper should be. I DON'T know what size the tip (0) dimension should be for a given rod length to make the rod throw a certain line size. That's where I need some guidance. Not trying to be a smart a$$ here - I genuinely appreciate the response. For anyone who's interested, there's a very nice Powell taper calculator that came with issue 10 of Power Fibers. This one will compute form settings for the A and C tapers, in addition to the B. Although some will argue that the A and C tapers can only be reproduced with a Powell style saw. (Bill Benham) I've made several "straight taper" rods & really like them. They're very smooth and easy to cast. Here are my assessments of line sizes. All of this is "empirical" - my opinion after actually fishing the rods: 8' / .290 per 100" / .068 tip - WF 6 or DT 5 - my all-time favorite rod 8-1/2' / .290 per 100" / .072 tip - WF 7 or DT 6 - really nice rod. 8' / .290 per 100" / .080 tip - WF 8 - Casts OK, though a bit soft for an 8 wt. 8' / .290 per 100" / .062 tip - WF 4 - can only cast about 30-40' comfortably - I ended up scrapping the rod for components. 7-1/2' / .290 per 100" / .068 tip - WF 5 or DT 5 - I loaned this rod to a guy who says it casts best with a $6.00 level line he bought at Walmart - I'm not sure if this is a compliment or an insult! 9' / .300 per 100" / .066 tip - WF 6 - nice rod 7' / .290 per 100" / .064 tip - WF 4 - nice rod for lawn casting, but I like a stiffer rod for small stream dry fly fishing. Just my opinions. Hope this helps. Also, my friend Bob Norwood has done a lot of research and analysis on straight tapers, and has developed some guidelines for rod length, slope, and tip dimension for each line size. (Tom Bowden) Let me start by saying I am no expert on this stuff. Nevertheless from my very limited experience I would suggest the following as a possible way of going forwards: I firmly believe the top 20" (and particularly the 5" to 20" section) of the rod define the line weight of the rod. Thereafter the rest of the rod can be made either 1) unnecessarily heavy (which is not a huge problem), 2) too light (which is a problem with longer casts) or 3)about right (which is obviously great). What I would do if I was you is the following; 1.) Work your numbers out starting with your tip of say 0.065. 2.) Enter them into Hexrod and save the rod. 3.) Use Hexrod to compare your rod with a Garrison of similar length and line weight (Garrison because his tapers are progressive and 'clean,' for want of a better word. 4.) Have a look at the top 20" (particularly the 5" to 20") of both rods in the combined graphs and check if the dimension graph lines roughly overlap. If so the chances are your line weight will be correct. Check the maximum stress as well. If not change the tip dimension, recalculate and repeat steps 2 and 3 until it works for you. 5.) Then for interest check how the rest of the rod compares. If your line is above the Garrison, the butt will obviously be stiffer. If below it will be lighter. If you have cast a Garrison taper this will give you an idea of what the difference might be like. Finally I would personally then consider reducing the tip dimension and the 5" dimension. This will make the tip more sensitive but won't detract from the power of the rod. And as a last comment I would personally use the A taper, but then I like a faster rod. (Stephen Dugmore)
I understand that Powell A tapers are milder, B moderate and C aggressive. What do the numerical suffixes stand for? Rod length, a fine-tuning of the ABC categories? In the calculator they run up to lengths that few would find practical. If you want a shorter rod you keep the same taper anyway? (Henry Mitchell) Wrong! All Powell tapers are derived mathematically. The B taper increases by a fixed amount from station to station towards the butt. Powell’s taper numbers such as the B-9 taper were based on 6" stations and $the amount of increase in a "strip." Thus B-9 was 0.009 increase in the strip over 6". That amounts to 0.018" section increase over 6" or 0.015" over the more typical, Garrison-like, 5" station spacing. That amounts to a taper increase of 0.003" per inch of taper. Now let's see what I can remember of the other two types, A and C tapers. The A & C tapers were calculated similarly to the B taper but with modifiers. For the A taper the station was calculated and then a small multiplier was added to the number that was based on the station position. In other words the closer you got to the butt the larger multiplier that was added to the straight line number. So that the A taper increased progressively above the straight line taper. The C taper was just the opposite. The small multiplier was subtracted from the straight line taper as you got closer to the butt. So that the dimension graph looked similar to some "Parabolic tapers". So, the B taper was just a straight line taper. An A taper that had the same starting numbers and slope should have a stronger butt than the B taper. A "C" taper having the same starting numbers and slope as a B taper should be a weaker butt. Unfortunately I can't find the exact formulas that I had from, I think Denver Dave or Tom Smithwick? I remember reading that the B taper was the most forgiving taper to cast of the 3. The other two A and C were more demanding of correct timing in the cast. Steelhead fishermen on the west coast seemed to favor the C taper in longer, heavier rods for long casts and heavy lines. Or so it was told to me by some forgotten make on this list or on Clark's old board. (Larry Swearingen) Larry and others there is a very good article in the Best of the Planing Form BOOK 2. (Gary Nicholson) Ah! That's where it was. Also I remember having emails discussions with Tom Smithwick about the tapers. Maybe 5 years ago? (Larry Swearingen) Thanks all, I'll check PFII. Isn't it funny that when we have an infinite number of tapers we'd like to make, and not enough time in which to do it, we can still get all curious about yet more? (Henry Mitchell) I understand that A tapers are milder, B moderate and C aggressive. What do the numerical suffixes stand for? The concept is actually fairly simple, Henry, but the devil is in the details. Basically, an A taper is what Powell called a progressive taper. The number after the A is the base slope of the taper in thousandths of an inch in a 6 inch length of an individual strip. Therefore if you had an A8 taper, that indicates a slope of .008 per 6 inches in a strip, but .016 per 6 inches in the glued up rod. To the base taper is added on a progressive increment, which I believe Powell expressed as a fraction of a thousandth. So the taper might be an A8 x 1/5, which would indicate an add on of .0002 per 6". So, the first 6" of the tip would have a taper rise of .008, the next six inches would rise .008 + .0002, the next .008 + .0004 the next .008 + .0006, and so on. All the numbers double when the rod is glued up. A "B" taper is a straight taper with no add on, so if you have a B9 taper, that's .009 per 6 " of length on an individual strip, or .018 in the glued up rod. A C taper is what Powell called degressive. It's the opposite of an A taper, in that the fraction of a thousandth is progressively subtracted from the base slope, producing a downward curving thickness chart, similar to a parabolic taper. Therefore, if you made all the tapers with the same slope. the A taper would be the fastest, the B more moderate, and the C the slowest. In practice, I don't think that's what Powell did. As I said, the devil is in the details. How much base slope, and how much to add and subtract. I just have not seen enough of these to give you any more guidance, but I hope this helps you understand the basic system. (Tom Smithwick)
I am wondering if anyone has (and would share) or knows where I can find any information on Mr. Powell's tapers. The only one I could find is in "HexRod Online" posted by Chris Raine for a 7'6" 2 piece 6 wt. Any help would be appreciated. I am trying to demystify his A-B-C system. (Bob Norwood) Best of the Planing Form Vol II has an extensive article on Powell tapers. (Frank Drummond)
I've been exploring Powell tapers lately. As you probably know, E.C. tapers are basically either straight, slightly progressive, or slightly regressive. Where does one start, for example, if he seeks a four weight taper? Or a five weight? Is .035" a good starting point for a five weight? (Harry Boyd) ~~~~ There is a calculator as Excel spread sheet by Carlin available here. It says it's for B tapers, but it also includes A and C tapers. I made an 8' B 8.7 taper starting at 0.038 which seems just right as a 6 wt. Here's the taper below as 3 piece. To get to other line weights I would use standard stress curve methods as in RodDNA or Hexrod. I have an article on the math of Powell tapers here. Powell himself spec'd his tapers with 6" spacing. To get the 5" equivalents for the A and C tapers you have to multiply his increment by (5/6) squared, that is 25/36 to get it right.
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