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    Re: The Bygrave
    From: Gary LaPook
    Date: 2009 Jul 31, 17:23 -0700

    You make it too hard. It is simple to print out the scale and try it
    on for size. Then you just adjust the printer commands to change the
    size of the printed scales and try it on again. A few iterations like
    this and you have a scale that fits on your cylinder.
    
    gl
    
    On Jul 26, 10:37�pm, Hanno Ix  wrote:
    > Dear waldendand:
    >
    > I have a technical question here:
    >
    > When you designed this scale, what exactly was the diameter of the drum and 
    the thickness of the paper? Did you perhaps make any experiments as to what 
    paper length fits exactly around the drum after it has been bend to a 
    cylinder?
    >
    > I see things this way:
    >
    > To fit precisely, the cylinder formed by the paper needs to have an inner 
    diameter equal to the outside diameter of the drum. So, because of the 
    thickness of the paper, the outside of the paper cylinder must be bigger yet. 
    As you bent the paper it will be deformed somewhat, and� the cylinder's 
    inside/outside diameters will probably be different from the original paper 
    length divided by pi. Since the scale is printed on the outside� this would 
    impact the accuracy of the scale. This error need not be big to cause errors 
    of a min or more.
    >
    > It seems difficult to predict the deformation of the paper, given the 
    complexity of its matrix. So I wonder, Is there anyone that has observed such 
    an effect in the practical world? If it was not negligible, how did you deal 
    with it?
    >
    > Similar questions apply, of course, to the next scale (cosine) and perhaps a third (cursor).
    >
    > If I were to make just a single Bygrave, I'd just turn the drum and/or play 
    with the scale plotting routine until things fit. However, if we are perhaps 
    talking about making a number of Bygraves we would need a more predictable 
    solution.
    >
    > Regards
    >
    > --- On Wed, 7/22/09, waldend...@YAHOO.COM  wrote:
    >
    > From: waldend...@YAHOO.COM 
    > Subject: [NavList 9186] Re: The Bygrave
    > To: NavList@fer3.com
    > Date: Wednesday, July 22, 2009, 7:15 PM
    >
    > Here's a revised version of a Bygrave scale.� I use a FORTRAN program to write out postscript text.�
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