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    Re: Bygrave formula
    From: Francis Upchurch
    Date: 2014 Jun 8, 22:54 -0700


    no worries re the names slip!

    I attach build details for the Bygrave and Fuller 2 replicas.They are both as accurate as the originals. I have since built probably my most useful slide rule (still prototype) A mini Fuller 2,  reduced size (same size as Bygrave) (photoshop), using 2 multiplication/division scales and one log sin scale from the original, but I have re-fromatted in the style of the Otis King, with no vulnerable metal cursers which do not work well on a bouncing boat! (more later, but it is faster and just as accurate (to 4-5+ decimal places).

    With regard to your idea,I will probably need a simple picture of how your 3 cursers fit over the single log scale. I assume I can use either the log sin scale from the Fuller, or the log cos scale from the Bygrave? Now where and how do the 3 transparent tube cursers go and how do you do the calculation?

    I can do the cosine formula no problem with the Fuller 2, but using it as a conventional slide rule with multiplication and division.(details also attached.)

    Building either is easy with minimal craft skills as long as you have the scales in PDF and can re-size on something like photoshop.No parallax type problems with the tubes/curser tubes, if everthing kept very close together (tight fit)

    Thanks for the kind thoughts re surgery pending. I'm like a beached whale until over that! But Im taking my mini Fuller 2 to the hopsital with me ,just in case!

    keep in touch

    Best francis

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