Sliderules
Some of the slide rules I have gathered over the years:
Contents
Sun Hemmi P280
Low cost two color simplex rule. Plastic body rule with unusual blue tinted slide and two color scales. Basic student rule with trig scales, the T, ST and S scales have complimentary angles marked in red, and the scales are all self-documenting on the right hand side. Reversible slide has 3 log log scales. Unbreakable plastic cursor.
- body: plastic
- cursor: plastic
- length: 27cm
- Scales: 13
- Front scale: T, K, A, [ B, CI, C, ] D, L, S, ST
- Slide Reverse: [ LL1, LL2, LL3 ]
- country of origin: Japan
- year of manufacture: October 1972 [Date Code: WJ]
Sun Hemmi Teledyne 44CA-600 Versalog II
About June, 1973. The last Post Versalog II is made. The first Teledyne-Post Versalog II (new model number 44CA-600) appeared a little before then, in June 1972. For a long time, the last T-P Versalog we knew of had the date code WH (August 1972), but a recently acquired Versalog 44CA-600 example has surfaced with the date code XF, indicating June 1973 production.
- body: laminated bamboo
- cursor: metal/plastic
- length: 27cm
- Scales: 24
- Front: logX, LL/1, LL/2, LL/3 [ T/T, SecT/ST, Cos/S, C ] D, LL3, LL2, LL1
- Back Scale: LL/00, K, A, DF [ CF, CIF, CI, C ] D, R1, R2, LL0
- country of origin: Japan
- year of manufacture: August 1972 [Date Code: WH]
Faber Castell 52/82
Plastic body duplex rule with trademark green accent stripes on fundamental scales, and multi-line cursor. Rule face is self-documenting, with scale functions listed, as well as scale letters.
- body: plastic
- cursor: plastic
- length: 10" (25.4)cm
- Scales: 22
- Front scales: L K A [ B BI CI C ] D LL1 LL2 LL3
- Back scales: T T2 DF [ CF CIF S' C ] D S ST P
- Country of origin: Germany
- year of manufacture: August 1961 [Date Code: 861]
Faber Castell 67/87
Plastic body simplex 15cm rule with 4-line cursor, two color (red/black) scale markings, and inch side ruler, reversible slide has S, ST, and T scales. Rule is self documenting on right hand side for all scales.
- body: plastic
- cursor: plastic
- length: 15cm
- Scales: 10 + ruler
- Front scales: K, A [ B, Ci, C ] D, L
- Back ruler scales: S, ST, T
- Country of origin: Germany
- year of manufacture: April 1959 [Date Code: 459]
Pickett N1006-ES
Pickett 5" Trigonometry Duplex Rule. This is the "Eye Saver" yellow version of this rule,
- body: aluminium
- cursor: nylon/plastic with metal screws
- length: 5" (12.7cm)
- Scales: 17
- Front scales: K, A [B, ST, T, S, C] D, DI
- Back scales: Ln, DF [CF, CIF, CI, C] D, L
- country of origin: USA
- year of manufacture: 1959
Pickett N600-ES
Pickett 5" Trigonometry Duplex Rule. This is the "Eye Saver" yellow version of this rule,
- body: aluminium
- cursor: nylon/plastic with metal screws
- length: 5" (12.7cm)
- Scales: 19
- Front scales: LL1, A [B, ST, T, S, C] D, DI, K
- Back scales: LL2, DF [CF, Ln, L, CI, C] D, LL3
- country of origin: USA
- year of manufacture: 1962-1964
The Scales
After seeing so many slide rules it may appear confusing to see so many scales close together one one slide rule. Here is a list of the most common slide rule scales.
Letter(s) | Description | Applies to | Colour | Orientation | Comments |
C | Single Logarithmic, 1 Decade (1-10) | Multiplication, division | Black | left to right | Usually found on slide |
D | Single Logarithmic, 1 Decade (1-10) | Multiplication, division | Black | left to right | Usually found on body |
A | Double Logarithmic, 2 Decades (1-10-100) | Powers of 2 and Square Roots | Black | left to right | Usually found on body |
B | Double Logarithmic, 2 Decades (1-10-100) | Powers of 2 and Square Roots | Black | left to right | Usually found on body |
K | Triple Logarithmic, 3 Decades (1-10-100-1000) | Powers of three and Cube Roots | Black | left to right | |
L | linear scale (0-1) | Mantissa for Common (base 10) Logs | Black | left to right | |
S | Sine scale | Sines between 5.7° and 90° | Black | left to right | |
S(cos) | Cosine scale | Cosines between 5.7° and 90° | Red | right to left, combined with S scale | |
T | Tangent scale | Tangents between 5.7° and 90° | Black | left to right | |
ST | Single Decade 1-10, basic scale folded at 57.3 | Sines, Tangents between 0.6° and 5.7° | Black | left to right | |
Ci | Inverted Single Decade 1-10 | Red | right to left | ||
Di | Inverted Single Decade 1-10 | Red | right to left | ||
Cf | Folded Single Decade 1-10 | Black | left to right | ||
Df | Folded Single Decade 1-10 | Black | left to right | ||
P | Pythagorean Scale | Black | left to right | ||
LL1 | Log-Log scale 1 | Raising numbers to arbitrary powers | Black | left to right | |
LL2 | Log-Log scale 2 | Raising numbers to arbitrary powers | Black | left to right | |
LL3 | Log-Log scale 3 | Raising numbers to arbitrary powers | Black | left to right |
Gauge Points
Often used numbers such as Pi, e, conversions and other ratios can be found as Gauge Points on some scales. Here is a list of common gauge points.
Symbol | Value | Name | Applicable to | Scales |
g | 0.01745 | sin(1°) | C,D | |
M | 0.31831 | 1/π | ratio of diameter to circumference | A,B |
| | 0.78648 | π/4 | Area and Circumference of Circles | C,B |
// | 1.182° | seconds in a radian, sin(1.1818) | ST | |
C | 1.273 | 4/π | Volume of a cylinder | C |
/ | 1.97° | minutes in a radian, sin(1.97) | ST | |
ℯ | 2.718281828 | Euler's Number | Natural Logs, compound interest, half-life decay | C |
π | 3.141592654 | Pi | ratio of circumference to diameter | C |
C1 | 3.5683 | SQRT(40/π) | volume of a cylinder | |
R | 57.299 | Reciprocal of Q | 1 radian = 57.3 degrees | Ci |
g′ | 3437.74 | minutes in a radian | Trig functions for small angles | |
g′′ | 206264.8 | seconds in a radian | Trig functions for small angles |