Faber-Castell 2/83N -62/83N

The 2/83N Novo Duplex was one of the last rules produced by Faber Castell and it is considered by some experts the finest and most beautiful slide rule ever made. It was manufactured in Germany from 1962 to 1976, the year Faber Castell ceased all slide rules and calculator production. Body and cursor were fabricated all plastic, and rule was hold with metallic braces. The cursor had several gauge marks for direct HP/kW and degrees to seconds conversions, and area of a circle calculation. The Novo Duplex model was produced in two sizes: 2/83N (rule 15 in long, scales 13 in long!) and 62/83N (rule 8 in long, scales 6 in long).

Its very robust set of 31 scales made it a favorite all purpose slide rule for scientist and engineers. The scales distribution was: T1, T2, K, A, DF [ CF, B, CIF, CI, C ] D, DI, S, ST, P on the front face, and LL03, LL02, LL01, LL00, W2 [ W2', CI, L, C, W1' ] W1, D, LL0, LL1, LL2, LL3 on the back face. One special characteristic of Faber Castell rules is its self-documenting scales, this is, its mathematical formula (with order of magnitude) appears at the right end of the scales. A special feature of Faber-Castell rules is the P scale, that allows to compute -in one step- the y-coordinate of the unit vector given the x-coordinate.

As you can imagine, the Novo Duplex is a classic, and a coveted jewel for collectors. Next are pictures of my collectibles:

Next is a link to a great 2/83N Simulator:

https://www.sliderules.org/react/faber_castell_2_83n.html

An skillful user was able to answer the next problems with two-three decimals precision:

SlideRulePractice-2.pdf

Note: Click on the next links to see professional panoramic pictures of the 2/83N and 62/83N models.

Next is the user manual for the Novo Duplex models in German, an English translation from the University of Delaware, and a Spanish version. something to notice the simplicity of this manual:

FaberCastell-2-83N-German.pdf
FaberCastell-283n-english.pdf
FaberCastell-2-83N-Spanish.pdf

References:

  • Stoll, Cliff: When the Slide Rules Ruled. Scientific American. May 2006, Volume 294, Issue 5

  • Smith Hughes, Richard: Watch your Ps and Qs -The Pythagorean Scales- Are They Worth the Effort? Journal of the Oughtred Society, Vol 15, No.2, 2006. https://osgalleries.org/journal/pdf_files/15.2/V15.2P50.pdf

  • Holland, Peter: Rechenscheiber/Slide Rule. A.W. Faber - A.W. Faber-Castell. Modelle, Typen, Skalen/ Models, Types, Scales. 2020 Digital Edition V 8.0. (This an extensive reference of Faber Castell rules models) Rechenschieber von Faber-Castell (sliderulemuseum.com)