Mirror Grinding Machine, G. W. Ritchey

Mirror Grinding Machine, G. W. Ritchey

     

George Willis Ritchey built this mirror grinding machine at the Yerkes Observatory in Williams Bay, Wisconsin, in the late 1890s. Under the sponsorship of George Ellery Hale, the machine was used to grind a series of telescope mirrors starting with a 24-inch and then a 60-inch mirror for a telescope initially intended for the Yerkes Observatory. The grinding machine was moved to Pasadena in 1904 to complete work on the 60-inch mirror. At some later time the apparatus was transferred to the California Institute of Technology. The Institute then sold the machine to the Lick Observatory of the University of California in 1949. The machine was used for making numerous mirrors over the next four decades and extensively modified over that period. It embodies the "sub-diameter tool" design approach to making large telescope mirrors whereby the grinding tool is drawn across the mirror blank by programmable rotating arms. It was donated to NASM by the Lick Observatory in 1993 and shipped in March of that year.

Gift of the Lick Observatory, University of California

Country of Origin
United States of America

Designer
George Willis Ritchey
Manufacturer
Yerkes Observatory

Location
Steven F. Udvar-Hazy Center, Chantilly, VA
Hangar
James S. McDonnell Space Hangar

Type
INSTRUMENTS-Scientific

Materials
Wood and iron construction, leather belts, steel hardware
Dimensions
3-D: 274.3 x 365.8 x 243.8cm (108 in. x 12 ft. x 96 in.)

George Willis Ritchey built this mirror grinding machine at the Yerkes Observatory in Williams Bay, Wisconsin, in the late 1890s. Under the sponsorship of George Ellery Hale, the machine was used to grind a series of telescope mirrors starting with a 24-inch and then a 60-inch mirror for a telescope initially intended for the Yerkes Observatory. The grinding machine was moved to Pasadena in 1904 to complete work on the 60-inch mirror. At some later time the apparatus was transferred to the California Institute of Technology. The Institute then sold the machine to the Lick Observatory of the University of California in 1949. The machine was used for making numerous mirrors over the next four decades and extensively modified over that period. It embodies the "sub-diameter tool" design approach to making large telescope mirrors whereby the grinding tool is drawn across the mirror blank by programmable rotating arms. It was donated to NASM by the Lick Observatory in 1993 and shipped in March of that year.

Gift of the Lick Observatory, University of California

Country of Origin
United States of America

Designer
George Willis Ritchey
Manufacturer
Yerkes Observatory

Location
Steven F. Udvar-Hazy Center, Chantilly, VA
Hangar
James S. McDonnell Space Hangar

Type
INSTRUMENTS-Scientific

Materials
Wood and iron construction, leather belts, steel hardware
Dimensions
3-D: 274.3 x 365.8 x 243.8cm (108 in. x 12 ft. x 96 in.)

ID: A19930093000