NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Another cylindrical bygrave
From: Hein Bodahl
Date: 2010 Jan 21, 14:26 +0100
From: Hein Bodahl
Date: 2010 Jan 21, 14:26 +0100
My apologies for going off topic. I renamed my answer from "[NavList] Re: Cylindrical Slide Rule tube poll" I have read the posting earlier and the version you describe is of course the inspiration for my idea. However it seems to me that the described version still would suffer from the problem of locking the scales while resetting the cursor. Mine would on the other hand, not be collapsible. Also, using shrink wrap tubes would eliminate the problem of "snagging" along the seems. The cursors printed on transparency sheets, laminated for stiffness. Properly cut and shrink wrapped around the tube I believe that it could make a better transparent outer tube than the adhesive pouch solution. Accurate cutting could possibly ensure proper friction. The simple beauty and extraordinary easy production and storage of your flat Bygrave is unfortunately slightly inhibiting of actual prototyping :-) Hein On 21.01.2010 13:01, Gary LaPook wrote: > See: > > http://www.fer3.com/arc/m2.aspx?i=108949&y=200907 > > gl > Hein Bodahl wrote: >> I have been thinking about using a 50 or 75mm drain pipe and fixed >> scales. >> Around that I would shrink wrap a movable cursor for the cos scale. This >> transparent wrap, lined to avoid undue friction, would also cover the >> cotan scale. >> >> Around the wrap covering the cotan scale I would wrap a second, movable >> cursor for the cotan scale. This second cursor would then move in >> conjunction with the cursor for the cos scale, once set, avoiding the >> locking problem.