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    Re: Double vial horizon prototype
    From: Randall Morrow
    Date: 2012 Jan 9, 11:56 -0800

       Thanks as always for the advice.    As long as the mirror and the plate surfaces are themselves parallel, they should be parallel to each other when the mirror is glued into place.   Correct?   To simplify flattening the face of the steel plate I thought I would get two plates, put the valve lapping compound across the faces and rub them together until all irregularities are gone.   This is similar to something I saw on a TV special about the reconstruction of the Parthenon in Athens.   Sand grit poured through holes in a flat steel plate would grind the surfaces of stones flat, allowing stacking to make  the columns.   The face of the metal plate would then be flat and it wouldn't require machining as was needed in the aluminum plate I use now.   If I remember my  geometry right, the rays of light should hit the plate and the mirror at the same angle if the two are parallel, despite them being separated by the thickness of the mirror.   Am I on track here?

    Randall F Morrow PT
    Kern County - Bakersfield

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    "Bill Morris" <engineer@clear.net.nz>
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    01/09/2012 10:49 AM

    Please respond to

    [NavList] Re: Double vial horizon prototype


    Be a little careful. Your new prototype levels the board. The surface of the mirror may be in a different plane.

    It's good to see that you have a vial production line going.

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