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: Borrowed Bygrave
    From: Gary LaPook
    Date: 2016 Jan 16, 11:29 +0000
    Obviously, I'm pretty proud of my creation, the Flat Bygrave. I would suggest hat if you are thinking of building a cylindrical model that you make a flat one first because it is so f***ing easy. If you already have the clear printer sheets then it will take you less than 5 minutes to download the two scales from my website and print them out on your printer and you will have a working Bygrave. Take it for a test drive.

    The cylindrical one is easier to use and feels better in your hand and has a historical connection but the flat one will give you a quick introduction to this delightful device that is just as accurate.
    Then, I suggest you make a simple tubular one using the method that I have posted in the past. And THEN, if you really like it, you can make a historically accurate one like those other guys have done, things of beauty. but requiring much more labor.

    gl




    From: David Pike <NoReply_DavidPike@navlist.net>
    To: garylapook@pacbell.net
    Sent: Thursday, January 14, 2016 5:17 PM
    Subject: [NavList] Borrowed Bygrave

    I’ve got the loan of a Bygrave Position Slide Rule MkIIA from the Royal Institute of Navigation for a couple of months (photos below).  Apparently, they had two, a good one and a poor one.  Unfortunately, I was only able to find the poor one; nobody seemed to know what happened to the good one.  It carries the inscription that it was produced by the Air Ministry Laboratory South Kensington in August 1920.  If the number was ever filled in, it’s long since rubbed off.  I’d like to teach myself to use it prior to possibly making a copy for myself with plastic piping.  Is the best set of usage instructions those on Gary’s Freddie Noonan page?  Also, does anyone know where I can find a photo or print out of the explanation off the side of the MkIIA?  Finally, does anybody know what went down the inside of the cylinders?  All I can see is the remains of a brass chain.  DaveP


    Attached File:

    (AML-Slide-Rule-1-Medium.JPG: Open and save)

    Attached File:

    (AML-Slide-Rule-2-Medium.JPG: Open and save)

    Attached File:

    (AML-Slide-Rule-3-Medium.JPG: Open and save)

    Attached File:

    (AML-Slide-Rule-4-Medium.JPG: Open and save)

    Attached File:

    (AML-Slide-Rule-5-Medium.JPG: Open and save)



       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    NavList is a community devoted to the preservation and practice of celestial navigation and other methods of traditional position-finding. We're a group of navigators, navigation enthusiasts and hobbyists, mathematicians and physicists, and historians interested in all aspects of navigation but primarily those techniques which are non-electronic.

    To post a message, if you are already signed up as a NavList member, start a new discussion or reply to any posted message and use your posting code (this is a simple low-security password assigned when you join). You may also join by posting. Your first on-topic messsage automatically makes you a member, and a posting code will be assigned and emailed to you for future posts.

    Uniquely, the NavList message boards also permit full interaction entirely by email. You can optionally receive individual posts or daily digests by email, and any member can post messages by email (bypassing the web site) by sending to our posting address which is "NavList@NavList.net". This functionality is similar to a traditional Internet mailing list: post by email, read by email, reply by email. Most members will prefer the web interface here for posting and replying to messages.

    NavList is more than an online community... more about that another day.

    © Copyright notice: please note that the rights to all messages and posts in this discussion group are held by their respective authors. No messages or text or images extracted from messages may be reproduced without the explicit consent of the message author. Email me, Frank Reed, if you have any questions.

    Join / Get 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