Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-26T11:24:15.499Z Has data issue: false hasContentIssue false

The use of diamond-impregnated tools for rock-slicing1

Published online by Cambridge University Press:  14 March 2018

K. C. Dunham
Affiliation:
Geological Survey and Museum, London
J. T. Taylor
Affiliation:
Government Training Centre, Letchworth

Extract

For the cutting of chips from rocks preparatory to thin-slicing, it has been standard practice for many years to use notched soft iron disks, manually armed with diamond powder. The latest machines employing cutting-disks of this type at the Geological Museum were built at the Government Training Centre, Ascot Works, Letchworth, to the design of the late Dr. H. H. Thomas and of Mr. W. Ward of the Centre. These are powered with 0.25 horse-power variable speed direct current motors, giving a maximum disk speed of 280 revolutions per minute. By means of rheostats, control of speed as sensitive as that obtainable with a treadle type of machine (see A. V. Weatherhead) is achieved. The normal speed for cutting is 160 to 180 r.p.m. In cutting a hard rock such as chert, it may be necessary to recharge the disk with diamond several times during the operation. The rock-specimen is held in a steel clamp with hardwood liners, mounted on a swinging arm. The rock is held in contact with the disk by the tension of a spring, or, during delicate work, by the pressure of the hand.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1950

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

1

Published by permission of the Director of the Geological Survey and Museum, and the Manager of the Government Training Centre, Letchworth.

References

2 Weatherhead, A. V., Petrographic micro-technique. London, 1947. [M.A. 10- 190.]Google Scholar

1 Alexander, A. E., Use of diamond laps in making petrographic and metallographic sections. Industrial Diamond Rev., 1942, vol. 2, p. 27.Google Scholar Anonymous, The production of quartz crystals. Ibid., 1944, vol. 4, pp. 56-58. Grodzinski, P., Diamond and gemstone industrial production methods?-V. Ibid., 1948, vol. 8, pp. 279-284. [M.A. 10-559.]Google Scholar

2 Hall, H. E. in Wulff, J. (editor), Powder metallurgy. Amer. Soc. Metals, Cleveland, Ohio, 1942.Google Scholar

3 Larson, E. T., Now it can be told. Industrial Diamond Rev., 1946, vol. 6, pp. 261-262.Google Scholar