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: Plath certificate: drop of solder
    From: David Pike
    Date: 2021 Feb 5, 10:04 -0800

    Seriously though, it’s a common feature of sextant certificates that companies tend to use the same basic certificates for decades with only minor updating.  Witness Hughes’ ladies with the bare ……s.  Although the certificate in question must be post-Litton, its quite possible that original drop of solder advice stems from towards the end of WW2 or even WWI when, because of the Allied blockade, there’s no saying which ersatz materials the Germans included in their torch batteries.  If the + cap to the carbon rod contained mainly brass (copper and zinc), the verdigris produced would be a mixture of Copper oxide, copper chloride, and copper carbonate depending upon how long the sextant or battery supplies spent at sea.  Although copper is an excellent conductor of electricity, oxides of copper are not.  That drop of solder (tin and lead) would prevent the build-up of verdigris.

    This is one of the reasons why if you rewire your boat or add extra electrical equipment, you should pay extra for tinned-wire connecting cable.  Otherwise, salt laden atmosphere gets up the cut ends of plastic-coated wire and starts to affect the conductivity of the induvial strands.  It’s the same if your TV reception at home starts to fail.  The chances are that rain’s got into the connecting cable from the aerial to the TV to produce copper carbonate. 

    The bare zinc on the - bottom of old-time dry batteries will also influence this cocktail, but that analysis a bit beyond my paygrade. DaveP

       
    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