Albert Nestler, Lahr in Baden / Germany (1945) ************************************************************** VERSION (C) S C A L E S of the NESTLER » E L E K T R O « Model 37 ============================================================== Front Side [ inverse / RED ] Back Side ============================================================== ( 0 .. 25 cm Ruler ) V X * 1.75 (A) PS X2 -------------------------------------------------------------- (B) KW X2 S sin(0.1X) [CI] [1/X] S&T arc(0.01X) (C) X T tan(0.1X) -------------------------------------------------------------- (D) X U X * 5.24 -------------------------------------------------------------- (LL2) exp(0.1X) = keyed to SCALE A and LEFT CURSOR-MARK (K) X3 The Slide Rule is LONGER and has a 30 .. 56 cm RULER IN BASE R E M A R K S : ( 1° = 60' ; 1' = 60" ) ============================================================== The TRIGONOMETRIC SCALES are divided in MINUTES & SECONDS The no-named scales are marked here with their common symbols in brackets: (A),(B),(CI),(C),(D),(LL2),(K). The U-Scale is folded by ( for calculating "Revol./Minute" ) π / 60 = 0.05236 The V-Scale is folded by the "Specific Resistance of Copper" sRcu = 0.0175 Ω * mm2 / m The CU-Marks for "Specific Conductivity of Copper" sCcu = 57.2 m / Ω * mm2 = 1 / sRcu The 736-Mark for 1 PS = 0.7355 kW with "Effectiveness"-Marks for MOT (=Motor) & DYN (= Dynamo) The Mark sqrt(2g) = 4.429 for "Pressure Hight" calculations There are 3 different Versions "Model 37" in this collection In this VERSION (C) the Inverse Scale [1/X] is added ... -------------------------------------------------------- The CURSOR HAIRLINES are symmetrical and in the common distance (on A-Scale) AREA/DIAMETER (on X-Scale). The LL2-Scale is placed OVER the CUBIC-Scale and SHIFTED, that CUBIC "52" is under LL2 "e" = 2 CURSOR SIDE-Hairlines. Have a look at VERSION (A) & VERSION (B) ... Historical Remarks ... The slide rule came in a black cardboard case. It is made of mahogany with scales on celluloid veneer. The back side's table with constants was in good shape. impressum: *************************************************************** © C.HAMANN http://public.BHT-Berlin.de/hamann 10/10/10 |