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Alexander Grant

  1. Nov 3, 2013 #1
    Hi All,
    I am working on a book regarding a famous fly fisherman that invented and made a fly rod out of wood more than 100yrs ago that cast a distance we still cannot match today, he was also a great violin maker/player and tuned his rod as he would tune his violin.
    Now bearing in mind a fly rod is tapered he managed to find the same vibration throughout the rod, he quotes.
    It is possible to find the action on a fly rod mathematically with no guess work.
    The balance of my rod - the "Grant Vibration Rod" - is made on the principle of vibration, complete in itself, with power for weight, leaving no discretionary power to the maker, and, with the moveable rings adapted to it, and with a correctly tapered line (which latter is difficult for line makers to follow out), the rod, line and rings is one harmonious whole with nothing loose anywhere.
    A taper on the rod such that the bending stress on the top and bottom fibers was constant along the length of the rod,(this was achieved by making acoustical measurements along the length of the rod).

    He was a brilliant mathematician and student of Nature that applied his knowledge to fly fishing over 100 years ago, I would be grateful for any input regarding Vibration qualities on a tapered wood and what pitch he would have listened for, I know he used a tuning fork along the length of the rod to get the same pitch.
    Thanks Gordon.
     
  2. jcsd
  3. Nov 3, 2013 #2

    UltrafastPED

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    Last edited by a moderator: May 6, 2017
  4. Nov 4, 2013 #3
    Thanks UltrafastPED,
    Alexander Grant when casting in 1896 did not shoot line like all morning fly casting, he lifted all the line and cast it without drawing in any line.
    Here is another Quote, I should say he also corresponded with Albert Einstein, he could work out the taper of a fly rod and the weight it would cast in his head often righting it down on a scrap of paper later to show his calculations .

    I have pursued my own theories on the laws or gravitation and nature with the result that nearly twenty years ago I discovered (what I could not find in the Euclidean third dimension) a fourth dimension- Relativity, but to explain this would require a new vocabulary briefly, i find that the measurements of the third dimension spacing will not agree anywhere with acoustical spacing. The fourth does, in dealing with variations in a material the relationship of the acoustics of the different parts supersedes all else.

    Acoustical spacing ? , and what he might have read around 1880.
    Thanks Gordon.
     
  5. Nov 4, 2013 #4

    CWatters

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    This page suggests that what he was trying to do was make a rod that had no discontinuities.

    http://www.speycast.co.uk/history-of-speycasting-alexander-grant/3059.html [Broken]

    For example by paying attention to the joints...

    This next section suggests his use of sound/vibration was to identify wood of similar or uniform density. Presumably to ensure no discontinuities in stiffness. This makes sense from a physics point of view. These days sound waves are used to detect anything from pockets of oil underground to cracks in aircraft. Many school children have put a ruler over the edge of a desk and given it a "twang" to make it vibrate. Would make perfect sense to do something similar with sections of a rod/wood to help sort them.

    I understand it's not difficult to break fly rods. I suspect that discontinuities concentrate stresses in a rod making it more prone to breaking? Presumably a rod without such stress points is stronger so the fisherman can put more power through it without breaking ??? Just my two cent worth.
     
    Last edited by a moderator: May 6, 2017
  6. Nov 4, 2013 #5

    AlephZero

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    It's a pity he didn't write down some actual math, rather than flowery Victorian English.

    That statement at least is comprehensible science, amenable to computer modeling for example. That's assuming the quote is what he actually meant, and not just somebody else's best guess.

    Stringed instrument makers usually "tune" the thickness of the different parts of the instrument by tapping them and checking the pitch of the sound by ear, to compensate for the variable properties of the wood. There's no reason why you shouldn't do the same to a fishing rod, but from your OP it's hard to guess exactly what his objective was.

    One way to make some progress would be to use modern vibration measurement techniques on his original rods (and lines, since your quote imply that he "tuned" the rod to the line), if any have survived in something close to their original condition. You could probably make a PhD project out of this, if you can find a university mech eng department with some fishing fanatics, and/or find a modern rod maker to sponsor the research.
     
  7. Nov 4, 2013 #6
    The quotes are from his own personal papers that I have, he also made fiddles and was head of the Strathspey reel society for 40 years, he was more interested in vibration and was applying it to musical instruments until his death in 1942.
    I would at some point like to make a Greenheart fly rod the same as I have all his exact drawings and wondered what piece of equipment would be best to find the exact vibration on each rod... I have one of his own rods.
    He could work out exact detail of taper design and splice and would only use a scrap of paper for each rod, there is so much more to the story of Alexander Grant who left school at 8 with almost no real education, could sit and talk about different dimensions in acoustical spacing and why they don't fit in the Euclidean third dimension.
    Thanks Gordon.
     
  8. Nov 4, 2013 #7

    UltrafastPED

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    Does this correspondence exist? It seems nebulous in the extreme.

    Note that "acoustical space" is the Fourier transform of the acoustic temporal wave into frequency space - if the frequencies correspond to vibrational modes of the structure, which is often true for musical instruments - a well trained person can hear or feel the vibrations.

    "These developments constituted the foundation for understanding the physical
    and eventually the physiologcial aspects of acoustics. In the attempt to grasp the
    nature of musical sound, Simon Ohm (1789–1854) advanced the hypothesis that
    the ear perceived only a single, pure sinusoidal vibration and that each complex
    sound is resolved by the ear into its fundamental frequency and its harmonics.
    Hermann F. L. von Helmholtz (1821–1894) arguably deserves the credit for laying
    the foundations of spectral analysis in his classic Lehre von den Tonempfindungen
    (Sensation of Sound). The monumental two-volume Theory of Sound, released in
    1877 and 1878 by the future Nobel laureate, Lord Rayleigh, laid down in a fairly
    complete fashion the theoretical foundations of acoustics."

    Chapter 1 from http://maji.utsi.edu/courses/08_aeroacoustics/ref_ac2_Science_and_Applications_of_Acoustics_2e_Raichel.pdf [Broken]
     
    Last edited by a moderator: May 6, 2017
  9. Nov 4, 2013 #8

    AlephZero

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    Hm... him and plenty more besides, who weren't crackpots but people who made useful practical discoveries and inventions, almost in spite of their strange theoretical ideas.

    A good example was Harrison (the first guy to build clocks accurate enough to determine longitude on sea voyages) who had some very strange ideas about vibrations and music. He was convinced all the standard theory of the physics of music was wrong, and the answer to everything was the ratio $$2^{(1/2\pi)}$$ ... which was of no relevance to anything much, until another guy called Charles Lucy found this in Harrison's papers and started making money from it. (I'm reluctant to post a near-crackpot web link to Lucy, but this stuff is easy enough to find on Google)

    Some pipe organ builders have been notorious (and intransigent) in their defence of bad physics as well. There were books published in the early 20th century "proving" that sound waves in air travelled along a pipe at different speeds depending on the diameter of the pipe. Of course they never actually measured the speed of sound propagation, but "trivial" issues like that didn't bother them in the slightest. Having learned the accepted wisdom and trade secrets of organ building, they just knew what was right and what wasn't. And they still built some magnificent instruments.
     
  10. Nov 4, 2013 #9
    Thanks Guys,
    I have read the story of Harrison and his sea going clocks made of wood and only wood, I believe one is still running in the museum in London, and on that NOTE there is a hand written letter on what is believed to be a stradivarius violin repaired and improved along side his own Violin called the Rondello.
    http://www.ambaile.org.uk/en/item/item_photograph.jsp?item_id=142059

    Thanks Gordon.
     
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