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
    Re: Borrowed Bygrave
    From: Francis Upchurch
    Date: 2016 Jan 17, 05:54 -0000

    Hi Wolfgang,

    I am ashamed to say, I was not aware of your MHRI masterpiece, which of course I now have to build! Your custom built tubes look better than my drain pipe off-cuts, especially the outer curser tube, which in my Bygrave and minifuller I had to make by hand.

    I would be very interested in obtaining some tubes for a new build project and likewise any details of the postscript scales. Please let me know costs and availability. Also, any advice on Post script editing? I have never been able to persuade my computer to take PS edit software.

    What sort of results are you getting with your MHRI?

    Best wishes.



    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Wolfgang Hasper
    Sent: 16 January 2016 19:57
    To: francisupchurch@gmail.com
    Subject: [NavList] Re: Borrowed Bygrave


    ... and, by the way, there are still plenty custom tubes for concentric slide rules in stock...


    contact me in case you want some.


    Dimensions are matching those of the MHR1 but the "true" Bygrave is almost identical.

    And the brilliant postscript code available  to generate the scales will take any diameter and either "Bygrave" or "HR" mode.






    Gesendet: Samstag, 16. Januar 2016 um 12:37 Uhr
    Von: "Gary LaPook" <NoReply_LaPook@fer3.com>
    An: wolfgang.hasper{at}web.de
    Betreff: [NavList] Re: Borrowed Bygrave

    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.





    From: David Pike <NoReply_DavidPike@fer3.com>
    To: garylapook---.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)


    View and reply to this message

    View and reply to this message

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    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 Settings

    Posting 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