Acu-Rule Acu-Math 511  
Written by Accutron on 2017-07-03  

Acu-Rule began in 1938 as the Festus Manufacturing Company, a Depression-era producer of affordable student-grade slide rules. Festus initially manufactured wood-body slide rules with paper scales, and also provided extra production capacity for other slide rule manufacturers such as Dietzgen and Post. By 1939, Festus had been renamed as the Acu-Rule Manufacturing Company, and soon began selling slide rules under the Acu-Math brand name.

The Acu-Math 511 is a 10" Mannheim-style simplex slide rule with nine scales and a non-reversible slide. The Acu-Math 511 is a later example of Acu-Rule's product line, featuring a magnesium body laminated with engraved vinyl scales.

Available Scales: S K A [B CI C] D L T

Acu-Rule Acu-Math 511 simulation, adapted from the Virtual Slide Rule script by Derek Ross.



Acu-Rule Acu-Math 511 10" Mannheim slide rule, obverse view.


Acu-Math 511 slide rule, reverse view.


Acu-Math 511 slide rule with box and soft case.

This article is part of the [Slide Rules] exhibit.

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