Welcome to the NavList Message Boards.


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

Compose Your Message

Add Images & Files
    Name or NavList Code:
    Re: Open a Mk IX bubble sextant
    From: David Pike
    Date: 2023 Nov 7, 12:25 -0800

    Michael Josefsson You wrote:

    Do you know if one has to break the shellac to remove the upper (or lower?) part of the bubble chamber? I imagine breaking the shellac can make it leak in the future.

    Or is there a hidden filling hole somewhere?

    No, no, no!  The MkIX is a Rolls Royce compared to an A12.  Leave the bubble chamber alone.  It's its reservoir tube on the side of the chamber you'll need to attack, but only if your sure you need to.  Are you sure you know how to make a bubble.  It needs practice, and once the skill has been learned, you can amaze your friends for years to come. 

    You need to look at Bill Morris' 'The Sextant Book' or some of the excellent stuff produced by Paul Brewer over the years.  Both ought to be available online. https://www.ebay.co.uk/sch/i.html?_nkw=mk+ix+bm+bubble+sextant+civilian+maintenance+handbook&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338792814&toolid=10001 . 

    The tube was nipped and sealed at the top with a blob of solder.  Paul manages to cut the blob off, tap the nipped bit, and put a tiny screw in.  I have to climb into the roof shortly.  I'll try and find one of my botched attempts to reseal with solder to show you.  My excuse; they must have had better solder in the 1940s and 50s.  When I find my phone I'll copy the bubble making page for you.  DaveP

    Browse Files

    Drop Files


    What is NavList?

    Get a NavList ID Code

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

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

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

    Email Settings

    NavList ID Code:

    Custom Index

    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