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    Re: Old sextant
    From: NavList Visitor
    Date: 2024 Jun 28, 22:08 -0700

    Dave and others, the horizon mirror is attached by two 5 BA cheese headed screws inserted from behind the frame. While the horizon mirror needs no great precision of placement, Heath in a 1931 sextant located the mirror by having the cheese heads fit closely in counterbores.

    The handle is in keeping with the early C20 sextant.

    Mirror clips will have to be made, though Cookes of Hull may have a few. The screws are 9 BA and are available on e-bay and perhaps from suppliers to model engineers. The shortest are 1/4 inch long and will have to be trimmed to length. The holes through the clips will need to be just over 2 mm, say 2.2mm in diameter. The brass will need to be a hard grade, though a softer brass can be hardened to make it springy by hammering it.

    Restoring old instruments can be challenging!

    Bill Morris

    Pukenui

    New Zealand

       
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