Sterling Metric Converter Slide Rule

Sterling Metric Converter Slide Rule

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Usage conditions apply
This ten-inch, one-sided plastic rule has a yellow base, a white slide, and a transparent indicator. Identical logarithmic scales are on the top and the bottom of the base. Both sides of the slide are marked with pairs of metric and conventional units. On one side, the user can read off conversions between: inches and centimeters; meters and feet; meters and yards; miles and kilometers; square inches and square centimeters; square meters and square feet (times ten); square meters and square yards; and square miles and square kilometers. The other side of the slide permits readings of cubic inches and cubic centimeters (times ten); cubic meters and cubic feet (times ten); cubic meters and cubic yards; liters and quarts; ounces and grams (times ten); kilograms and pounds; metric tons and short tons; and gallons and liters.
The top left of the base is marked with the letters SP in a circle and the word STERLING. The top middle of the base is marked: METRIC CONVERTER. The bottom left of the base is marked: MADE IN U.S.A. The rule was received with its original packaging, a clear plastic cover on a blue paper backing. The packaging is marked at the top: SP STERLING #651 (/) metric (/) converter. At the bottom, it is marked: BORDEN ® (/) © 1972 STERLING PLASTICS (/) DIVISION OF BORDEN CHEMICAL, BORDEN INC. (/) MOUNTAINSIDE, N.J. 07092 (/) MADE IN U.S.A.
Sterling Plastics, a 20th-century manufacturer of drawing instruments for schools, was purchased by Borden Chemical in 1970. Since Sterling stopped making slide rules in 1972, this example of model number 651 was probably one of the last rules produced by the company. The five braces holding together the base of the instrument are also consistent with this date; early Sterling slide rules had only two braces. For instructions, see 1990.0689.03. For a Sterling slide rule with standard scales, see 1988.0807.01.
Reference: Mike Konshak, "Sterling Plastics,"
Currently not on view
Object Name
slide rule
date made
Sterling Plastics
place made
United States: New Jersey, Mountainside
Physical Description
plastic (overall material)
paper (case material)
overall: 1 cm x 34.5 cm x 9 cm; 13/32 in x 13 19/32 in x 3 17/32 in
ID Number
accession number
catalog number
Credit Line
Gift of George A. Norton III
Rule, Calculating
Conversion Chart
See more items in
Medicine and Science: Mathematics
Metric System
Science & Mathematics
Slide Rules
Measuring & Mapping
Data Source
National Museum of American History
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I occasionally buy vintage slide rules especially if they're in a leather Case. I was in a thrift store as I am periodically looking for interesting things and came across a sealed plastic bag with many different things including two still sealed in their package Sterling 651 slide rules. I bought the bag actually thinking I could always use a metric converter the price was so low I gave it very little thought and when I got out to my car I opened the bag and googled the slide rule and that brings me to this point. I thought you might find it to be an interesting story. I enjoyed your writing it was very informative and I was very surprised at what I had bought, thanks again.
Been using slide rules since 1950. Still using slide rule for calculations and I am a Marine Engineer. so the calculations undertaken are not casualThe beauty of a slip stick./ guessing stick ? is its ability to function at all temperatures.Used it once in Quebec to calculate ballast weights to be moved for stability on a ship where all had frozen all the way to the top of mast in layers of ice. but also INCLUDING the my calculator's batteries..Still have three in my desk but now most often used in the STERLING metric convertor. ------- At 78 years old who the hell wants to learn a new system with a Sterling around I can think in one system and calculate in another.

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