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    Re: Cylindrical Slide Rule tube poll
    From: Richard M Pisko
    Date: 2010 Jan 24, 13:13 -0700

    On Thu, 21 Jan 2010 04:52:32 -0700, Gary LaPook 
    > The following was originally posted on July 4, 2009 as message #8949.
    Gary, I clipped almost everything from the above post that showed your
    Bygrave version built on a thin chrome plated tube, from a sink drain, I
    think.  Assembly was pretty straightforward using clear, sticky on one
    side film for protection and as construction material, though you warned
    about watching the direction of overlap to avoid "ratcheting".
    My version, built on a 1-3/4 inch diameter cardboard tube 11 inches long,
    is not as nice as that or your newest larger diameter cylindrical rule
    with the HR1 locking feature.
    I just didn't like the idea of close fitting aluminum tubes rubbing on
    bare paper, lacquered or varnished paper, or even plastic coated paper.
    Including the thin felt layers to gently rub on any of the above surfaces
    is my preference.
    My cursor tube is opaque, with an oval window cutout and pointer for the
    short tube, and a pointer for the long tube.  I have a stop on the outer
    tube so the cursor tube window mark is lined up with the lowest spiral of
    the midle tube (which reads 4 degrees at the lower end); and the basic
    instruction diagram is printed half on the middle tube and half on the
    cursor tube right over the stop line.  There is still about four inches of
    blank paper showing at one end of the inner tube; can't seem to make it
    any shorter than that and still have enough travel and easy handling.  The
    middle tube can be removed accidentally from off the end of the inner
    tube, but it doesn't happen during calculations.  Does the Bygrave inner
    tube telescope at all, and have a knurled cap to prevent this accidental
    Richard . . .
    Using Opera 10

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