A.W. Faber-Castell 67

The 67 pattern slide rule family by A.W. Faber-Castell is a series of pocket size slide rules starting in the fifties. It contains several variations of layout including revisions over time.

67/54 Darmstadt
TypeSlide Rule (Pocket)
ManufacturerA.W. Faber-Castell
IntroducedC. 1955
Successor67/54 B Darmstadt
Calculator
Precision2 to 3 Significant Digits
Display typeAnalogue Scales, Sliding Cursor (multiple hairlines)
Display size5" (pocket)
Programming
Other
Dimensions15 cm (approx. 6")
67/87 Rietz
ManufacturerA.W. Faber-Castell
IntroducedC. 1955
Successor67/87 b Rietz
Calculator
Precision2 to 3 Significant Digits
Display typeAnalogue Scales, Sliding Cursor (multiple hairlines)
Display size5" (pocket)
Programming
Other
Dimensions15 cm (approx. 6")

OverviewEdit

The 67 pattern of slide rule is a line of simplex rules in several layouts. They are characterized by being made of "Geroplast" plastic, with scales engraved into the plastic. Most sported scale extensions on the C and D scales, with many having extensions on the A and B scales as well. Most members also sported multiple hairlines on their cursor, which facilitated quick calculations and single-setting options for common operations.

R Model VariantsEdit

For most of the available models, the blank space on the back gave enough room to fit a six digit Addiator adding machine, along with various references and conversions. For all models with an R variant available, the adjustments to the layout will be described.

67/54 DarmstadtEdit

The model 54 Darmstadt was a pocket version of the highly popular Darmstadt layout. It sported a cursor with at least two secondary hairlines which helped with finding the area of circles with known diameter, among other things. Faber-Castell marketed this model towards physicists, engineers, mathematicians, and university students.

LayoutEdit

the model 54 was an archetypal Darmstadt layout, typical of most simplex slide rules with this designation. Notable in this layout are the inclusion of a P scale and a lack of an ST scale, as well as the inclusion of LL scales, which is unusual for a simplex rule.

FrontEdit

in. L K A (B CI C) D P S T

BackEdit

(LL1 LL2 LL3)

Note that this is a simplex rule. All scales on the back are used by inverting the slide, which limits some operations. The later 54 B model added windows to the back which allowed for use without inverting the slide.

R ModelEdit

the 67/54 R Darmstadt made no layout changes for accommodating the Addiator on the back. The RB model had no rear window for LL scale use without inverting the slide.

67/87 RietzEdit

The model 87 Rietz was consistent with layouts seen more typically in the US.