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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Cylindrical Slide Rule tube poll
From: Hein Bodahl
Date: 2010 Jan 20, 14:08 +0100
From: Hein Bodahl
Date: 2010 Jan 20, 14:08 +0100
On 20.01.2010 06:38, Richard M. Pisko wrote: > I think a felt liner would be almost essential for prolonged use. > Aluminum tends to blacken surfaces through rubbing. A coating of the > paper or plastic would help, and I had even thought of spraying the > inside of the outer tube with a thin film of drawing fixative; but I > believe that felt would be the best solution. How about protecting the scales with a PVC shrink wrap tube ? http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200255742807 A while back Martin Tali posted PostScript files for the scales, it seems to me that using those would be the easiest way to handle the scaling problem of different diameter tubing. 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. This would also provide a cylinder to store the necessary tables. Perhaps... Hein