Hinges in a Bamboo Rod Taper

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jan96
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Re: Hinges in a Bamboo Rod Taper

#21

Post by jan96 »

Mr.Andersen, this is one of Your tapers publicly available I printed more than twenty years ago... It has a "hinge" at 70''. I must admit that I never built a rod with this taper.. I suppose the intent was that rod would flex more at that "hinge" point/area... What would be the advantage comparing this taper to a one without that hinge? Thank you. :)
r :)
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Don Andersen
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Re: Hinges in a Bamboo Rod Taper

#22

Post by Don Andersen »

jan96 wrote:Mr.Andersen, this is one of Your tapers publicly available I printed more than twenty years ago... It has a "hinge" at 70''. I must admit that I never built a rod with this taper.. I suppose the intent was that rod would flex more at that "hinge" point/area... What would be the advantage comparing this taper to a one without that hinge? Thank you. :)
r :)
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Jan,

The amount of droop is insignificant @ the 70” mark. May have been a entering error. Is the info from Ray Gould’s book?

Don

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Re: Hinges in a Bamboo Rod Taper

#23

Post by Caneghost »

Interesting discussion. I am not a maker, simply a bamboo fisher. I had one rod from a very well respected rod company that I bought that definitely had a hinge. I had cast the two piece version of that rod and liked it a lot, so when I had a chance to aquire the three piece I thought - better for travel and a little bit more power in the mid - perfect. But the 3 piece had a very noticeable hinge in the mid. When you extended the line for a longer cast it folded and would not make the longer casts. I tried easing and slowing my power stroke but it didn't matter. That rod just folded and the line ran out of steam beyond that distance.

I also have a Sweetwater Trout Bum, made by Wyatt Dietrich in his Geo. Maurer Memory Series that was listed in Maurer's catalog as a semi-parabolic rod. That rod is wonderful! Works close and casts as much line brilliantly as you might chose. Ain't no hinge in that one baby! So I guess designed in hinges are something that takes a lot of trial and error to perfect. Thoughts?
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mer
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Re: Hinges in a Bamboo Rod Taper

#24

Post by mer »

Canewrap wrote:Mer, now I understand what you're thinking. A swell is not what I am referring to when I talk about a 'hinge'. A swell interrupts the flow of energy and is not something desirable when it's a sudden jump. But, I suppose a sudden increase in taper could be looked at as a hinge. That's why I am trying to come up with a different term for what I am talking about. There are useful swells, like a swelled butt that stops the action. Also, a gradual increase in taper halfway down the butt can expand the useful line weight range. But, it can be tricky to introduce a swell, since it can turn a good rod into a dog with just a few thousands of an inch.

No, what I am talking about is a flatter increase in the taper, which is pretty much the opposite of a swell.
Your last sentence is exactly what I was saying in post #7: "A swell is the opposite of a hinge". My confusion came from you in post #8:
"Mer - uh, no it is not the opposite of a swell, that would be a regression."

But then you last sentence seems to be agreeing with what I said.

I'm not referring to the effect a hinge or swell has on a rods actions, but merely the defining characteristic which for both is "a change in the rate of increase for a taper". One the rate of increase is less (flatter, hinge) the other the rate of increase is greater (swell).

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Re: Hinges in a Bamboo Rod Taper

#25

Post by Tom Smithwick »

"So I guess designed in hinges are something that takes a lot of trial and error to perfect. Thoughts?"
Exactly so. What likely happened in your case, however, is that the taper was not changed to accommodate the extra ferrule weight when used for a 3 piece rod instead of a two piece. You might get away with that on a high sloped fast action taper, but a more moderate actioned taper might not be able to handle the extra weight, causing the hinge effect and reduction in performance.
On the other hand, the deliberate parabolic hinge in front of the grip that Quashnet referred to is a tricky balance to achieve. If it's too floppy, the rod just won't cast the line well at all, too stiff, and what you get is just a too heavy progressive action rod. Both Ritz and Young seem to have made a lot of prototypes to get that group of tapers just right.

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Re: Hinges in a Bamboo Rod Taper

#26

Post by Adamsdry »

I love a hinge and the "kick" they induce. A familiar casting rhythm becomes almost hypnotic.
I first questioned drops in tapers near the grip when I first started building. The responses I got were some of the most generously gifted replies I've ever received as a member. I was ushered into this craft by a very tolerant, non judgmental, giving community.
Thanks again, from the new, old guy.

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D
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jan96
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Re: Hinges in a Bamboo Rod Taper

#27

Post by jan96 »

Don Andersen wrote:
jan96 wrote:Mr.Andersen, this is one of Your tapers publicly available I printed more than twenty years ago... It has a "hinge" at 70''. I must admit that I never built a rod with this taper.. I suppose the intent was that rod would flex more at that "hinge" point/area... What would be the advantage comparing this taper to a one without that hinge? Thank you. :)
r :)

Jan,

The amount of droop is insignificant @ the 70” mark. May have been a entering error. Is the info from Ray Gould’s book?

Don
Sorry Don, my mistake. When calculating from inches to millimeters I wasn't accurate enough. It can be seen on the original "stress curve" graph that there is no hinge in the taper. But if we take it theoretical, if there would be such a drop in the slope...?
r :)

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Re: Hinges in a Bamboo Rod Taper

#28

Post by Canewrap »

mer wrote:
Canewrap wrote:Mer, now I understand what you're thinking. A swell is not what I am referring to when I talk about a 'hinge'. A swell interrupts the flow of energy and is not something desirable when it's a sudden jump. But, I suppose a sudden increase in taper could be looked at as a hinge. That's why I am trying to come up with a different term for what I am talking about. There are useful swells, like a swelled butt that stops the action. Also, a gradual increase in taper halfway down the butt can expand the useful line weight range. But, it can be tricky to introduce a swell, since it can turn a good rod into a dog with just a few thousands of an inch.

No, what I am talking about is a flatter increase in the taper, which is pretty much the opposite of a swell.
Your last sentence is exactly what I was saying in post #7: "A swell is the opposite of a hinge". My confusion came from you in post #8:
"Mer - uh, no it is not the opposite of a swell, that would be a regression."

But then you last sentence seems to be agreeing with what I said.

I'm not referring to the effect a hinge or swell has on a rods actions, but merely the defining characteristic which for both is "a change in the rate of increase for a taper". One the rate of increase is less (flatter, hinge) the other the rate of increase is greater (swell).
Ok, now we're on the same page.

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Re: Hinges in a Bamboo Rod Taper

#29

Post by Canewrap »

[/quote] I also have a Sweetwater Trout Bum, made by Wyatt Dietrich in his Geo. Maurer Memory Series that was listed in Maurer's catalog as a semi-parabolic rod. That rod is wonderful! Works close and casts as much line brilliantly as you might chose. Ain't no hinge in that one baby! So I guess designed in hinges are something that takes a lot of trial and error to perfect. Thoughts?[/quote]

Hate to burst your bubble, but if it is described as semi-parabolic, it has a hinge or two in it. But, it's the type of hinge I've been describing and not the negative version that either causes a rod to run out of steam too soon (too flat in the wrong place) or makes a rod too stiff (too much of a swell in the wrong place). Yep, designed in hinges, as Tom says above, need to be perfected. I've been working with designing in hinges since I came back to roadmaking four years ago. In my opinion, well designed hinges allow the greatest range of casting capability.

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Re: Hinges in a Bamboo Rod Taper

#30

Post by henkverhaar »

Jan, conversion error. 0.265 inch would yield a form setting of 3.37, not 3.25

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Re: Hinges in a Bamboo Rod Taper

#31

Post by jan96 »

henkverhaar wrote:Jan, conversion error. 0.265 inch would yield a form setting of 3.37, not 3.25
I noticed that, thank you Henk :)
r :)

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Re: Hinges in a Bamboo Rod Taper

#32

Post by Caneghost »

OK so there are good hinges and bad ones then. The first rod I mentioned actually felt like it buckled at one point along the blank when the line was extended in casting. Tom's explanation makes sense, that the taper wasn't modified to allow for ferrule weight. With that rod it was sudden: smooth casting, let out another couple of feet of line on the backcast and then FOLD!

The Sweetwater never felt like it hinged at a point like that, instead the opposite, smooth casting then extra power kicked in. Funny that the bad hinge came from a much for famous maker than the good one. Perhaps my casting accentuates it. I was a child of graphite and learned on that. I may push some of my cane rods harder than others who started with cane or fiberglass, though generally bamboo helps me relax and cast! It flows you know. You don't have to really power a good rod like the stiff plastic ones, you just feed it.

I would guess that, in the bad rod, the reduction in taper may have been more drastic, what perhaps an extra thousandth?
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Re: Hinges in a Bamboo Rod Taper

#33

Post by RSalar »

I think this topic needs to be revisited. I'd like to understand why a hinge does anything great. If you want the rod to flex lower to aid in roll casting then just reduce the slope between stations. I can't see how a "weak spot" (which it is or the rod wouldn't hinge there) is of any benefit. Then again I am a greenhorn so please bear with me
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Re: Hinges in a Bamboo Rod Taper

#34

Post by Canewrap »

Ok, since I use "hinges" all the time in my rod designs, let me try to explain this a little more clearly. It is not a real hinge in the taper that we are talking about. Wayne Cattanach coined the term to refer to what it looks like in a stress graph. A "hinge" is actually as you suggest, a reduction in the taper increase. For example, say the taper increases somewhere from .013 to .017 every five inches along the taper (Dickerson 7613 is a good example and the taper numbers I use below from the Lovely Reed book). This is a fast rod. However to make the tip better able to cast in close, this taper has a hinge at 40 inches. It only increases .010 for these five inches (35 to 40). This allows this area to start flexing before the cane in front of it. This is a subtle difference, but it does contribute to the overall feel of the rod as it casts.

Inches Diameter
5 0.082
10 0.098
15 0.115
20 0.128
25 0.142
30 0.158
35 0.175
40 0.185
45 0.206

Likewise, in the butt, where a rod is increasing in, say .018 to .020 per five inches, an increase of only .006 for a five inch segment allows the rod to form a loop more easily, while roll casting. You'll notice, in my next example that from 65 to 75 the diameter doesn't increase as much as the taper in front of it.

60 0.252
65 0.272
70 0.278
75 0.288

This is not a weakness, but rather a flatter spot in the rod. It is not a true hinge, it was just described that way because of how the stress graph looks (like an inverted V) when examining how the rod would load under stress. Hopefully, this helps clear this up. These flatter spots are very useful when working with a rod that has a fast taper or is fairly short and doesn't have the built in mass to naturally flex under its own weight for close-in casts or short rollcasts.

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Re: Hinges in a Bamboo Rod Taper

#35

Post by Don Andersen »

Ah ha, the hinge locally known as “the limp inch in the middle. “
Or the floppy butt or butt swinger.
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Re: Hinges in a Bamboo Rod Taper

#36

Post by Bill M. »

"Does the average user understand what the concept of 'hinges' means?"

This user, probably below average, but with a lot of experience, does not understand the concept of hinges. Even after reading the above posts. Maybe even more confused after reading.

I do have a couple of rods built supposedly on Dickerson tapers, a 7' and a 7.5'. and I do love the way they cast. I also like the three 7.5' Perfectionist taper rods I have cast.

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Re: Hinges in a Bamboo Rod Taper

#37

Post by RSalar »

Canewrap wrote:
08/05/21 13:59
Likewise, in the butt, where a rod is increasing in, say .018 to .020 per five inches, an increase of only .006 for a five inch segment allows the rod to form a loop more easily, while roll casting.
So if you took that rod with that "hinge" and mounted it to a bench or on a wall and just attached the butt then hung a weight on the tip or just bent it down by hand would that weak area or hinge be visible in the way the rod bends? And if so why is that better than just having the whole rod bend to the same amount at the tip? Why does the hinge "allow the rod to form a loop more easily?"

Thanks
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Re: Hinges in a Bamboo Rod Taper

#38

Post by Canewrap »

I don't know if I am being baited into explaining this in a hundred different ways, but I will try once again to explain the principle and answer your questions. No, if you put weight on the end of the rod, it will still describe a smooth arc and this feature allows the caster to "feel" the rod load at shorter distances, which allows for better control and easier loop formation. It does not weaken the cane, which is what you're suggesting by suggesting that it might be seen in a static deflection test. If you don't understand how this can help to have a rod that can both be felt to load in close and reach out to longer distances without being parabolic and subject to the limitations that a parabolic rod imposes, then I can't help any further. I know it works, I know why and will continue to work with this in my designs. If you read Wayne Cattanach's comments concerning the "hinge" in the Sir D taper, you might recall his comment that a lot of the classic tapers included a version of this to help with rollcasting. Thinking about this as I write it, this feature simply allows better casting feedback and hence better control.

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Re: Hinges in a Bamboo Rod Taper

#39

Post by mrampant »

I personally like this type of rod design although a friend of mine who is a world class caster detests them.
I think to best understand this concept it is best to watch someone casting the rod and watch the rod bending. the difference between the types of rod; one that has a "hinge" and one that doesn't becomes glaringly obvious. The photo that Quash posted of Summers casting highlights this.
So, whether you like them or not the design is a "design" for a particular type of rod action.
My AUD$ 0.02 worth of info.
Cheers, Mark
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Re: Hinges in a Bamboo Rod Taper

#40

Post by cdmoore »

Just need to apply a startup-y name to it to wipe away that negative connotation.

Hynj? Henk V. should get a kick out of that one.

Rollcrum?

Lessening?

Pivot?

Crux?

Dwndl?

Ebb?

Quell?

Slackening?

A wane? or maybe a Wayne?

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