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    Re: How not to level an AH
    From: UNK
    Date: 2014 Jan 24, 09:13 -0800

    Hi All
    Several points were made about my ball bearing level:
    -Örjan, I was trying to get portable precision for almost no money. My sighting ability doesn’t need to get into nanometers. I agree, a level is the way to go.

    -Bruce, $124 should get you a precision of closer to 0.0005” per foot – not per inch of a torpedo level. That would give 0.0024 degrees, 0.14’, or 8.6 seconds. Plenty good enough for position finding. The Starrett level is perfectly satisfactory for leveling – just a bit heavy to position on my little AH structure without changing the setting, probably twice as heavy as everything else I’m carrying around, and nice enough that I spend too much time covering the bubble glass and putting it back in its box. It has no model number or specifications that I can find but I’d hate to level one that was more sensitive.

    -Bill Morris, I agree about the force vectors trying to move the ball. I’m supposed to be able to do that analysis but it was easier, and more fun, to spend $5 and play. I guess I was coming from the perfectly round and perfectly flat and smooth point of view and hoped that little ball would just keep trying to roll. Wrong, and I shared so someone else won’t waste $5.

    -I conclude now that the ultimate AH would have two small precision levels at 90 degrees as several people have described. I’ll add that, for sun sights, the mirror should be changed to black glass or clear glass painted on the back side. It’s easy for your eyes to get a flash from the sun using a first surface mirror. That must be where the pirates got the Arrgh!
    Regards, Noell

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