Perrygraf Machining Calculator Slide Rule for LeBlond
date: label: date made
content: 1949
name: label: maker
content: Perry Graf Corporation
notes: label: Description
content: This yellow and white rectangular paper rule has a white paper slide and is held together with four metal rivets. On the front, the top scales allow one to calculate the revolutions per minute for a given work diameter and surface speed. The bottom scales allow calculation of the time in minutes and seconds for a given feed rate, length of cut, and R.P.M. The back of the instrument has tables for converting from fractions to decimals and for finding the suggested carbide surface speed of a lathe for different materials.
label: Description
content: Perrygraf Corporation, described in 1979.3074.03, made this instrument in 1949 for the R. K. LeBlond Machine Tool Company of Cincinnati. A salesman could attach his card to the back of the calculator and give it to a client. Richard K. LeBlond (1864–1953) began making machines in 1887 and became known for the quality of his lathes in the 1890s. Products included lathes for manufacturing bicycles and automobile crankshafts. The company employed 1,200 workers and made a mammoth lathe for boring artillery during World War II. In 1981 Makino Corporation of Japan purchased the company. The factory in Cincinnati is now Rookwood Pavilion shopping center.
label: Description
content: Perrygraf slide rules in the collection include: 1983.3009.04, 1983.3009.05, 1983.3009.06, 1987.0108.03, 1988.0323.01, 1988.0325.01, and 1992.3103.01.
label: Description
content: References: Tom Wyman, "Slide Chart Calculators – A Modest Proposal," <i>Journal of the Oughtred Society</i> 13, no. 1 (2004): 6–10; Kenneth L. Cope, <i>American Lathe Builders: 1810–1910</i> (Mendham, N.J.: Astragal Press, 2001), 89; Tony Griffiths, "LeBlond - USA," <i>Machine Tool Reference Archive</i>, http://www.lathes.co.uk/leblond/.
label: Location
content: Currently not on view
place: label: place made
content: United States: Illinois, Maywood
topic: label: Subject
content: Mathematics
label: Subject
content: Rule, Calculating
label: Subject
content: Manufacturing
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Science & Mathematics
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content: Slide Rules
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1992.3103.01
label: nonaccession number
content: 1992.3103
label: catalog number
content: 1992.3103.01
objectType: label: Object Name
content: slide rule
physicalDescription: label: Physical Description
content: paper (overall material)
label: Measurements
content: overall: .2 cm x 18.5 cm x 8.8 cm; 3/32 in x 7 9/32 in x 3 15/32 in