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
    Name or NavList Code:
    Email:
       
    Reply
    Re: Temperature range of bubble sextants?
    From: UNK
    Date: 2017 Jan 16, 15:38 -0800

    Hi Tony,
    The short answer to your first question is: they don't stabilize the bubble for temperature. The various types of bubbles are adjustable at the time of use and, usually, removed, or the bubble system is relaxed when not in use.

    Many bubble systems are at nearly atmospheric pressure and have a side chamber for the "air". There is a method of making the air chamber larger or smaller and specific instructions tell you how to position the sextant to put air into the chamber for a smaller bubble or to put air into the sight path for a larger bubble.

    Some bubble assemblies use a specific fluid, I think installed under a partial vacuum, absolutely no "air" in the system, and a strong metal diaphragm connected to a thumbscrew to reduce the fluid pressure until a small amount of fluid in the sight path "boils" into vapor and creates a bubble. These are much harder for mere mortals to work on.

    There are many posts available if you search for "refill bubble".
    Regards, Noell

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Get a NavList ID Code

    Name:
    (please, no nicknames or handles)
    Email:
    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:

    Email Settings

    NavList ID 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