Triangulation applied to sheet metal pattern cutting : a comprehensive treatise for cutters, draftsmen, foremen and students ... (1920)
Kidder, F. S. (Fred SMith), b. 1863 · New York : The Sheet Metal Publication Company · leaf 71
an of one-half of the top, and the small semi-circles constitute a plan of one-half of the base. The next step is to determine what amount of the larger semi-circle shall be devoted to each small semi- circle, or, in other words, what part of the top shall be devoted to each of the small collars.… … Fig. 42. Semi-plan. We may now divide each of the semi-circles into an equal number of equal parts as shown from 1 to 9, and from 10 to 18. If each semi-circle is divided into eight parts, as here shown, the point F is located without further trouble, thereby locating six points as A, B, C, D, E…
Sheet-metal work
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
