Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    Re: A-12 Bubble Sextant (Octant)
    From: Jean-Philippe Planas
    Date: 2014 Feb 11, 23:01 -0800
    Hello,

    I am afraid the easiest way to proceed would be to buy a new bubble illumination assembly including the rheostat. The best way would be to purchase a wrecked A12 on Ebay making sure the bubble illumination assembly is present and to canibalize it.I own several A12s presently but don't consider parting with them at the very moment.
    Good luck
    JPP



    On Monday, February 10, 2014 8:27 PM, J.M. Kalouguine <kaloujm{at}free.fr> wrote:

    Thank you for the tip, but unfortunately in spite of all of your advise I've tear down the zinc tube to peace... Certainly to brutal! I collect the complete rheostat . Do you know if it is possible to by an other one or rebuild the body and re using the original rheostat?
    -------------------
    This message was posted in reply to:
    http://fer3.com/arc/m2.aspx/A12-Bubble-Sextant-Octant-Planas-sep-2010-g14003
    From: Jean-Philippe Planas
    Date: 2010 Sep 22, 22:57 -0700
    Hello,

    To make it short.

    If the bubble illumination assembly is not inserted in the sextant you can remove the bubble assembly by just twisting it a degree or two and pulling on it.
    If the bubble illumination assembly is present, remove it first as the bulb interferes with bubble assembly when you pull it out.
    If the bubble illumination assembly is stuck, then proceed as descried here;
    http://jphtechnologies.wordpress.com/2009/12/20/137/

    To adjust the sextant, just back off the screw (with an Allen or similar wrench) that links the index mirror on this axis to free the mirror and reposition it to a correct postion for instance using polaris or during LAN. When the bubble is centered and the vernier indicate the precomputed reading, tighten the screw back.

    You may then fine tune the index error by adjusting the vernier which is position with two screws at boths ends.

    Good luck and please keep us posted on your progress.

    JPP
    ----------------------------------------------------------------
    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]fer3.com
    ----------------------------------------------------------------
    View and reply to this message: http://fer3.com/arc/m2.aspx?i=126854


       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.
    Email:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site