Kenison, Ervin, Gardner, Harry W, Lawrence, William Henry, 1868-, Everett, Herbert E. (Herbert Edward), 1863-1932, Gregg, D. A. (David A.), Von Holst, H. V. (Hermann Valentin), 1874-1955, Brown, Frank Chouteau, 1876-1947, Griffin, Charles Lewis, 1867-, Neubecker, William, 1864-, Zapf, Alfred E, American School (Lansing, Ill.) · Chicago, Ill. : [American School of Correspondence] · leaf 541
SHEET METAL WORK 129 form of a spiral, the method of drawing the spiral will first be shown. Establish a center point as a' in Fig. 14-2, and with the desired radius describe the circle shown, which divide into a polygon of any number of sides, in this case being 6 sides or a hexagon. The more… … 5 and draw out each side indefinitely as 1 2 b, 3 c, 4 d, 5 e, and 6yi Now using 2 as center and 2 1 as radius, describe the arc 1 A; then using 3 as center and 3 A as radius, describe the arc 523
Mechanical drawing
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