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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Cylindrical Slide Rule / tube lengths
From: Wolfgang Hasper
Date: 2010 Jan 27, 21:37 +0100
From: Wolfgang Hasper
Date: 2010 Jan 27, 21:37 +0100
I received a sample of those laminated paper tubes. The exterior surface is very smooth and even, rather matte than glossy. I am sure it can be used to put on printed scales without further treatment. By the way: I found white adhesive film in A4 size that can be used in a laser printer. the interior surface is glossy, due to production on a core tube. (it is a coiling production process. No noticeable seam or other irregularity from the coil end on the outside though.) For ease of transport and to save on cost there the tubes should be cut to length at the manufacturer's. They provide precise cuts to right-angles which I think is a huge benefit and valuable help for our futher work. I will shortly receive information on the cutting cost. As I find only now those lengths are not sufficiently known yet. RvR's paper gives account of the visible: inner tube something > 230mm with 198 mm of scale intermediate tube 225 mm outer/cursor tube 222 mm (this is reliably the true length of the tube) The intermediate tube will for sure extend into the base and end just before the "upper" cursor cut-out (marked II). (assumed cursor tube on zero stop) So the inner tube is visible there. The inner tube itself will be long enough to be sufficiently stabilised when fully drawn out, yet short enough to leave some space for the locking mechanism down in the base region (when slide rule is fully closed) Assume the black base is a "cup" slipped on the end of the intermediate tube. I will make a sectional drawing to determine the missing lengths and post it for discussion. Any comments welcome. Would you please tell me if anybody wants to have non-HR lengths? Wolfgang