NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Wolfgang Hasper
Date: 2016 Jan 17, 20:19 +0100
Von: "Francis Upchurch" <NoReply_Upchurch@fer3.com>
An: wolfgang.hasper@web.de
Betreff: [NavList] Re: Borrowed Bygrave
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.
Francis
From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Wolfgang Hasper
Sent: 16 January 2016 19:57
To: francisupchurch---.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.
Regards
Wolfgang
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.
gl
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)
