Bill, If you have a friend on another site, Sexy Loops, that has invented the term "harmonic curve of frequency vs added weight" that is fine and I hope it is something that is useful to you. But do not expect me to understand what your friend means by these words. That is a term that in my experience engineers do not use. Your last paragraph suggests to me a lack of understanding
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Russell, No, I am sorry I do not have any 6DJ8s around. It has been a lot of years since I used any of them. I will bet that you can find some though on one of the internet @#$%& sites. You can somehow impact the scope and it will ring at the resonant frequency. The same frequency that it will oscillate at if you deflect it and release. As I mentioned previously it is very difficult to ma
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Bob, I would wholeheartedly agree that with you that when you are writting the written word is a very dangerous thing. I am poor when it comes to spelling but I do not hold a candle to you. You are either a world class bad speller or you have more imagination when it comes to spelling then anyone I know.
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Bill, I think that you are wrong about not being able to tell your two rod examples apart if you would allow me to look at them. I could tell a great deal about them. For example, just as a start the one with the lowest resonant frequency will be the one with the lowest stiffness if they are the same length or if they have simular stiffness the one with the lowest resonant frequency will be th
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Russell, If you have a scope it is very easy. The most straight forward way is to mount a photo resistor in series with a second resistor and apply a small voltage, say 5 volts, across the two resistors. Then connect the input to your scope across the photo resistor and from a short distance away shine a light on the resistor while you deflect the rod tip and release it allowing it to oscillat
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Bill, I think that you are right about the usefulness of resonant frequency to the average fisherman. But I think that being able to compare one blank to another is probably enough and very useful for most rod builders. And how much more can be done with it is determined by how well you understand it. It has been a very important tool for electrical and mechanical engineers and physicists for
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Bill, I do not understand what you are attempting to get at. And, please, it is not a question of marketing @#$%&, it is a question of physics. Resonant frequency has been a useful tool to electrical and mechanical engineers and physicist for a couple of hundred years.
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Tom, You are right I cannot take a blank or rod that I know nothing about and tell you from the resonant frequency what the action or power or or length or the material it is constructed from is. But I do not think that is what the custom rod builder normally wants to know. What he want to know is something like, how much does this set of guides improve the performance of this blank or how muc
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Bill, I think that you and I must have been typing at the same time. And I think that you and I are very much in disagreement. First of all, to be accurate it is not really the weight that affects the resonant frequency and it is also not the mass either it is the inertia that is a result of the mass and is also a function of the velocity of the mass. Actually if you look at Kaufman's formula
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Tom, I agree with most of your points but not all. RF is certainly most useful for comparing one blank or rod to another as you point out but then what you can infer from the difference is what is really important. And once you have experience using RF then the rod that is being compared against can be a mental one. Actually, I think that if you think about it all measurements are comparisons
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Bill, Because all of the characteristics of the blank or rod show up in the resonant frequency manufacturers can, for example, use it to measure the characteristics of blanks over time as a quality control tool, to insure that their processes or their materials are not changing over time. They can also use it as a quantitative measure of a blanks improved performance when they change the mater
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Eugene, I worked for Tektronix for many years on this type of equipment and that is the reason that I have it and use it often. I do not think that you want to try to duplicate it though. However, these days this type of equipment is very inexpensive on the internet. But the equipment that I use is really overkill for measuring blank or rod resonant frequency. The type of inexpensive device
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Ben, You make a good point. John Kaufman was interested in golf clubs resonant frequency so his formula tends to be optimized for that. However, it will still work for rod blanks and is the best formula for blank resonant frequency that I have seen. If you are familiar with calculus, I think that what is really needed is a calculus term dM/dL which is change in mass by change in length. Bas
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Bill, I would tend to agree with those that posted that the human hand cannot detect the difference in the mass of guides if the difference is small and IF the rod is being held steady or with no movement. However, once the rod is put into motion very small differences in the mass of the guides and the frequency of resonance can be detected. Try this experiment, shake one of your rods that has
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Joe, You're absolutely correct. A higher resonant frequency means that the tip velocity will be higher during the cast. The rod with the higher resonant frequency will release the stored energy more rapidly than a rod with a lower resonant frequency. Or another way of putting it is that the rod with the higher resonant frequency will convert the stored energy to kinetic energy more rapidly.
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Bobby, This is not some sort of new scientific theory that requires peer review for confirmation. It is just straight forward engineering. Every physical structure has a resonant frequency, a pipe, a beam, a two by four, a bridge or a carbon fiber blank and the measuring of the resonant frequency of physical structures has been taking place for I would guess a couple hundred years. Some r
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Ben, It is the rods or blanks natural frequency or resonant frequency or first harmonic. Different disciplines often use different terms but it is the rate that the blank or rod will oscillate if stimulated (deflected and released). The resonant frequency of golf clubs are also measured using the same technique as is used with blanks or rods. It has become fairly common for the shafts in a
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Eugene, I missed your comment earlier, It is not really the stiffness or the total weight it is the mechanical impedance which is determined by the square root of the mass density times the elasticity.
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Steve, The hardness of the material has absolutely nothing to do with the velocity that vibrations travel up a rod. The velocity is a function of the mechanical impedance of the material. The mechanical impedance is determined by the elasticy and the mass density of the material. Though not absolutely correct you can think of the mass density as the weight per unit of length and the elasticit
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Phil, Well, all I can say is those people are flat wrong. I can prove, mathamatically prove, that added weight will reduce sensitivity and I can also measure it. That is unless you have some other definition for sensitivity other than how much of the energy in the fish's bite gets to the fisherman's hand. I know that there is a lot of talk about balance and sensitivity but to put it very blun
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Phil, Added weight will REDUCE the rods sensitivity regrdless of where on the rod you put the weight and whether or not the added weight results in the rod being balanced.
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Phil, Yes, he can add weight to balance the rod but in my judgment the price that the extra weight extracks is too high. The extra weight compromises all of the other important performance characteristics of a rod. Chris, I agree with most of your points but would add this. You can go to Walmart and buy very inexpensive rods that are made from cheap, low modulus blanks with durable, heavy
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Joe, You have done a bunch of things to make this rod durable. Unfortunately the things that you have done, large reel seat, shrink wrap over the cork, double footed guides, double wrapped guides and I will bet that you also used size D thread as well which holds more epoxy, will all add weight and reduce the rods performance and also make it feel tip heavy except maybe the shrink wrap. The w
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Peter, I may get some argument on this but I think that all decorative wraps look better when done with A thread as opposed to D including tartans. And with tartans the layer underneath shows up better with A than with D. It takes longer and you have to be a little more careful with packing but when you are through I think the results are worth the additional effort.
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Justin, I have built a number of rods from that blank and have not seen anything like you are describing. Take Tom's suggestion and get in touch with the Batson's. As he says they are great people and I strongly suspect that they will want to replace that blank.
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Josh, The sturgeon in the Columbia River get a lot larger than 100 to 200 pounds. I have hooked numerous ones that weighed 600 or 700 or 800 pounds. Never landed any that big though. I have seen pictures of sturgeon that were 15 and 16 feet long. The tackle used is a function of how you are fishing for them. Much of the fishing is done from a boat and heavy short rods are used. Rods that a
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Greg, Peter is right. There is nothing that compares in size and scope to the Expo but we do have a get together of rod builders that Lamiglas hosts in April. We usually get over 100 rod builders mostly from the Northwest but there are also a few from Canada. It lasts for two days with quite a few seminars and displays by other blank and component manufacturers other than Lamiglas. You shoul
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You are correct Roger about the stiffness being mainly a function of the diameter. Stiffness goes up at the third power of diameter for a tubular blank and at the fourth power for a solid blank so there will be some difference but not a huge difference. However, the solid blank will have much higher hoop strength or strength against shear, torsion and crush. The difference in hoop strength wil
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You will get the maximum distance by casting a material that has a very high density and is shaped so that it has the smallest frontal area like a tubular piece of lead. You will get the maximum distance with a given input energy if you can achieve a 45 degree trajectory. The dimples in a golf ball if the ball is rotating creates lift but I do not see how you will be able to duplicate this wi
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Gary, I think that the primary property that people are feeling is the blanks or rods resonant frequency. But I agree with your basic point. The blanks or rods damping and also sensitivity are determined by the same variables that determine the resonant frequency.
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