NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Borrowed Bygrave
From: Gary LaPook
Date: 2016 Jan 16, 11:29 +0000
From: David Pike <NoReply_DavidPike@fer3.com>
To: garylapook@pacbell.net
Sent: Thursday, January 14, 2016 5:17 PM
Subject: [NavList] Borrowed Bygrave
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)
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@fer3.com>
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)
