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    Re: Cylindrical Slide Rule tube poll
    From: Richard M Pisko
    Date: 2010 Jan 22, 22:04 -0700

    On Wed, 20 Jan 2010 06:08:28 -0700, Hein Bodahl  wrote:
    > How about protecting the scales with a PVC shrink wrap tube ?
    > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200255742807
    That sounds better than the stick on clear protective film I used for book
    > A while back Martin Tali posted PostScript files for the scales, it
    > seems to me that using those would be the easiest way to handle the
    > scaling problem of different diameter tubing.
    Yes indeed.
    > I have been thinking about using a 50 or 75mm drain pipe and fixed
    > scales.
    > Around that I would shrink wrap a movable cursor for the cos scale. This
    > transparent wrap, lined to avoid undue friction, would also cover the
    > cotan scale.
    > Around the wrap covering the cotan scale I would wrap a second, movable
    > cursor for the cotan scale. This second cursor would then move in
    > conjunction with the cursor for the cos scale, once set, avoiding the
    > locking problem.
    Interesting solution.  Sort of like a circular slide rule with the two
    plastic arms and the cursor drawn on each (instead of two disks and one
    cursor); but you could avoid the problem of finding the right segment of
    spiral by using a blunt arrowhead instead of a line.  I would miss being
    able to see both figures at the same time as a last check, perhaps.
    > This would also provide a cylinder to store the necessary tables.
    Yes, and the manual.  :-)
    Richard . . .
    Using Opera 10

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