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-10 Sextant Maintenance Manual
    From: Jean-Philippe Planas
    Date: 2007 Dec 8, 07:06 -0800
    Hi Arthur,

     The bubble assembly has to be refilled with xylene which is some kind of a paint solvent.
    You have to separate the bubble assembly from the main sextant body.
    1- Unscrew the 2 small screws that maintain the lighting arrangement below the assembly.
    2-Unscrew the 4 main long screws to separate the bubble assembly from the optical system.
    3-Unscrew the bottom lens of the bubble assembly
    3-1 with a wristwatch caseback wrench,  unscrew the lens retainer ring.
    3-2 carefully remove with a blade the metal and paper compression gaskets
    3-3 unstick the lens with a thin blade or a suction cup
    4 Remove the thin lead inner gasket and be prepared to replace it by neoprene O ring that fits in the lead gasket channel. The O ring is about 1.5mm thick by 20mm diameter.
    5 Take out all remaining fluid by operating the  enlarger knob back and forth
    6 Clean the lens and inner of the bubble assembly with fresh xylene and Q-tips
    made of natural cotton
    7 Pour fresh xylene into the cavity (top it up) and work the enlarger knob back and forth to eliminate air from the reservoir. Repeat the operation until no more bubbles appear from the reservoir.
    8 Top up again the cavity with xylene
    9 Place neoprene O ring in place and lens
    10 Replace paper and metal compression gaskets above the lens
    11 Replace the bottom lens retainer ring and screw it by hand only
    12 With your fingers of one hand applying controlled pressure on the top and bottom lenses, with the other hand carefully work the enlarge-reduce knob until a small bubble appear
    13 Tighten the bottom retainer ring with the watch caseback wrench

    Check the bubble after one or 2 days. If it grows you will have to repeat the process. Sometimes it is necessary to repeat the process numerous times until you get a stable bubble of the right size (about 1.5 or 2mm diameter)

    The enarge reduce pump system will most likely not be working anymore as these bubble assemblies used to be filled under a vacum to correctly operate as specified.

    Hope this helps

    JPP




    glapook---.net wrote:

    Gary writes:

    I will look at my A-10 manual tonight to see if it has this
    information.

    gl

    On Dec 6, 11:56 am, Camelot wrote:
    > I need assistance in loading or refilling the bubble on an A-10 WW II
    > Air Force Sextant. If you can help, or direct me to help, please
    > replThank you.
    >
    > Arthur Hill

    Never miss a thing. Make Yahoo your homepage.
    --~--~---------~--~----~------------~-------~--~----~
    To post to this group, send email to NavList@fer3.com
    To unsubscribe, send email to NavList-unsubscribe@fer3.com
    -~----------~----~----~----~------~----~------~--~---

       
    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