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    Re: SNO-Ts on eBay with Horizon Mirror Installed Backwards
    From: Alexandre Eremenko
    Date: 2012 Mar 31, 13:16 -0400

    Yes, I saw them:-)
    Well, the same "dshop" offers two sextants with correctly placed
    mirrors. I suppose that the two you are talking about had
    bad mirrors, he obtained spare mirrors somewhere and installed them
    incorrectly. These two are the older ones, by the way (1977 and 1978).
    The other two he offers are of 1980-s, and the price is the same.
    Bill Morris actually says that the standards for the early ones
    where higher: he cited a specification showing a 1976 one with 3"
    guaranteed max arc error, while in 1980-s  and after they have 6".
    I don't know when they changed this standard.
    
    Alex.
    
    P.S. Don't buy the one with incorrectly installed mirror!
    Bill M says in his book: "This mirror is attached by two cheese headed
    screws from behind. One screw is longer than another and
    ON NO ACCOUNT SHOULD THE LONG SCREW BE INSERTED THROUGH THE THINNER
    part of the frame as to do so RISCS STRIPPING THE THREAD OR DAMAGING
    the mirror". I checked my sextant, it looks indeed that the mirror can
    be reversed, but as Bill says this can cause a damage, and perhaps
    the damage has already been made.
    
    
    > Amazing. If you look at the images of the 4 SNO-T sextants offered on eBay
    > by the Latvian chap (the ones with the yellow open boxes) you will notice
    > that the first two have their horizon mirrors installed backwards, with
    > the mirror side facing the sea horizon and the adjustment screws facing
    > the index mirror.
    >
    > I have not got Bill's book yet but I guess it is not a big deal to remove
    > them and reinstall them correctly.
    >
    >
    >
    > View and reply to this message: http://fer3.com/arc/m2.aspx?i=118604
    >
    >
    >
    
    
    
    
    

       
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