Grindsted Products Metric Converter Slide Rule

Grindsted Products Metric Converter Slide Rule

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Usage conditions apply
This rule consists of a clear plastic envelope, glued together along the back bottom edge, and a white plastic slide. The front of the rule has six windows for reading off conversions between yards or feet and meters; centimeters and inches; square yards and square meters; square centimeters and square inches; cubic meters and cubic yards; and liters and imperial gallons or U.S. gallons. The front also has tables of equivalents and a scale for converting between Fahrenheit and Celsius temperatures. The top right corner is marked: GRINDSTED (/) PRODUCTS, INC. (/) Research for quality (/) 2701 ROCKCREEK PKY. (/) NORTH KANSAS CITY, (/) MISSOURI 64116. It is also marked: TEL: 816-842-6500 (/)TELEX: 4-2565 (/)GRINDSINC NKSC. A table for decimal equivalents between fractions, millimeters, and inches runs down the middle of the slide.
The back has six windows for reading off conversions between pounds and kilograms; ounces and grams; PSI and atmospheres or kilograms per square centimeters; inches or centimeters of mercury and PSI; BTU and kilocalories or watt hours; and meter-kilograms and foot-pounds or joules. The back also has more tables of equivalents.
Grindsted is a Danish brand for bulk food products, such as animal feed and emulsifiers for human foods. In 1989 it merged into the Danish conglomerate Danisco, which in turn was purchased by DuPont in 2011. The logo on this rule was in use from 1975 to 1991. Grindsted's factory in the Kansas City suburbs opened in 1975 and filed an annual report in 2012. Compare this rule to metric converters 1990.0689.01 and 1990.3231.01. For the style of manufacture, compare to 1988.0795.02.
References: "Articles of Incorporation of Grinsted Products, Inc.," Missouri Secretary of State Business Name History,; "History - DuPont Danisco,"; U.S. Patent and Trademark Office, Trademark Electronic Search System.
Currently not on view
Object Name
calculating rule /slide chart
date made
Grindsted Products, Inc.
place made
United States: Missouri, North Kansas City
Physical Description
plastic (overall material)
overall:.2 cm x 21.6 cm x 8.8 cm; 3/32 in x 8 1/2 in x 3 15/32 in
ID Number
catalog number
nonaccession number
Credit Line
Transfer from Division of Engineering and Industry
Conversion Chart
See more items in
Medicine and Science: Mathematics
Measuring & Mapping
Science & Mathematics
Slide Rules
Metric System
Mathematical Charts and Tables
Data Source
National Museum of American History
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