Perrygraf Machining Calculator Slide Rule for LeBlond

Object Details

Perry Graf Corporation

Description

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.

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.

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.

References: Tom Wyman, "Slide Chart Calculators – A Modest Proposal," Journal of the Oughtred Society 13, no. 1 (2004): 6–10; Kenneth L. Cope, American Lathe Builders: 1810–1910 (Mendham, N.J.: Astragal Press, 2001), 89; Tony Griffiths, "LeBlond - USA," Machine Tool Reference Archive, http://www.lathes.co.uk/leblond/.

Location

Currently not on view

1949

ID Number

1992.3103.01

nonaccession number

1992.3103

catalog number

1992.3103.01

Object Name

slide rule

Physical Description

paper (overall material)

Measurements

overall: .2 cm x 18.5 cm x 8.8 cm; 3/32 in x 7 9/32 in x 3 15/32 in

place made

United States: Illinois, Maywood

See more items in

Medicine and Science: Mathematics

Science & Mathematics

Slide Rules

National Museum of American History

subject

Mathematics

Rule, Calculating

Manufacturing

Record ID

nmah_1215063

Metadata Usage (text)

CC0

GUID (Link to Original Record)

http://n2t.net/ark:/65665/ng49ca746a9-96ad-704b-e053-15f76fa0b4fa