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: Traditional navigation by slide rule
    From: Bob Goethe
    Date: 2016 Oct 28, 12:19 -0700

    It seems like most of the items I find when I search for "plano convex plastic lens" are circular.

    >>Try "Bar magnifier" instead. It would find something like this $3 unit which you can scratch a hairline on and cut to right length.<<

    This idea seems to have real merit.  In addition to cheaper, they are typically rectangular, and indeed I should be able to cut one down to size. 

    I can get by The Mall this weekend (if you are from Edmonton, you can hear it in a person's voice when they using uppercase to describe The Mall - which in our context means the West Edmonton Mall; largest mall in the world up until year 2004, and only 3 km from my house) and purchase 2 or 3 different ones of these and try them out for cheap.  Thanks!!

    Bob

       
    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