A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Robin Stuart
Date: 2016 Jan 15, 09:20 -0800
The hard won results of Brad's survey of MHR1 scale design were faithfully, warts and all, into one of the Bygrave scale designs available here http://fer3.com/arc/m2.aspx/Postscript-code-for-making-Bygrave-Scales-Stuart-jan-2015-g29918.
The documents therein describe an alternative form of Gary LaPook's flat Bygrave. In 2014 before he passed, Hanno Ix, had been very interested in trying to further develop the flat Bygrave design. Instead of using a transparent cosine scale as Gary does, he would transfer measurements between scales using a beam compass. For posterity I attach a couple of the flat Bygrave designs I produced at Hanno's request. The second of these makes use of the fact that the cotan scale is symmetric about 45° and allows both scales to be accommodated on a single sheet.
Wolfgang Hasper was the "fellow in Germany" who produced the mechanical drawings http://fer3.com/arc/m2.aspx/Bygrave-Hasper-apr-2011-g16123. He also also had tubes specially made for the purpose. The end product can be seen here http://fer3.com/arc/m2.aspx/MHR1-reproduction-Hasper-mar-2011-g16039