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Re: slide rule
From: Paul Hirose
Date: 2010 Apr 27, 11:43 -0700
From: Paul Hirose
Date: 2010 Apr 27, 11:43 -0700
Hewitt Schlereth wrote: > > Shufeldt's skide rule is a Keuffel & Esser Log Log Duplex Trig. Log > Log means it has logarithm scales. Duplex means it has scales on both > sides. Trig means the trig scales are in degrees and minutes. His rule is one of the K&E 4080 family, a good choice for someone wanting to get into slide rules nowadays, since it's got a full assortment of scales for science and engineering, yet is plentiful and affordable on eBay. I wrote about it at some length last year: http://www.fer3.com/arc/m2.aspx?i=108309 Keuffel & Esser completely changed their numbering system in the early 1960s. A 68 1256 is equivalent to the earlier 4181-3. The years of the deteriorating plastic in the top and bottom cursor bars are not precisely defined; I've read that K&E changed to an improved plastic as late as the late 1940s. As far as I know, the rules with all-plastic bodies used the later material and had no problem. One of my 4181-3s was awarded as a prize by the Texas Chemical Council in 1963, and looks brand new. (Apparently the recipient already had his favorite slide rule, and never used the prize.) I believe all Pickett rules use decimal trig graduations, so would not be suitable for the original poster. On the other hand, most simple slide rules with the classic 9-scale arrangement seem to have used degrees and minutes. This would include the K&E 4053, Post 1452, and Sterling Precision. --