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Prints not exact to scale?

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Aug 14, 2007
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Hey all,

I'm not sure if this is a problem with my prints or normal and I'm being too picky. I'm going over all of the prints and starting to cut out parts (gussets) for the wing ribs. I'm using a laser cutter and was translating the prints into CAD drawings. When I started measuring the dimensions on the prints, my ruler doesn't match the numbers on the ribs. For example, sheet 12 on the upper wing tip rib, the drawing shows from the leading edge to centers of each truss 4 3/8, 10 3/8, 16 3/8 ... I'm getting 4 3/8, 10 7/16, and16 7/16 respectively. the length of the rib on the print says 35.5, but I measured it at 35.625. There's an extra 8th inch. Is this a problem or am I being too precise? I was hoping to use the print to compare my parts to. All of the rib sheets are off an 8th here or a 16th there.


- Matt

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