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    Re: Bowditch octant
    From: Jared Sherman
    Date: 2004 Nov 22, 13:43 -0500

     If you are printing your scales in a laser printer, you may find errors
    caused by the laser process. The paper is "moist" from room humidity, and
    then gets steamed (literally) and pressed against the fusion roller. This
    causes enough physical change in the paper so that it may change in length,
    i.e. from the nominal 11" in US-letter sized paper, by plus or minus 1/32"
    to 1/16".
     In order to avoid this, you must use an engineering mylar or other
    non-paper material designed for laser printing. Some of the synthetic papers
    are actually latex based and no better in this regard. I'm not sure how
    Kimdura (similar to Tyvek) competes but would think it falls in between
    paper and mylar.
     With inkjet printers you have a different problem, the wet ink saturates
    the paper and on most printers you can see it visibly pucker and distort
    while it is coming out. This distortion is local and uneven, varying with
    the ink. Again, a non-paper product is the answer, and any of the synthetics
    should do. Since there is no fusion drum to steam them, there's a wider
    range of materials to be found. Craft supply stores often have a wider range
    than office supply stores, with special materials for stenciling, etc., made
    of more durable or thicker stock. Setting the inkjet to "draft" or "economy"
    mode so it uses less ink may also help.
     For the best precision in "custom printing" one offs, we used to work
    directly with digital film imagesetters, which produce black image on
    transparent film stock. That's very stable in all dimensions, but might cost
    you $5-10 per page from a local imagesetting service bureau. (May shift a
    bit if you get it wet though!)

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