Items related to Practical sheet metal work and demonstrated patterns...
Practical sheet metal work and demonstrated patterns Volume 11; a comprehensive treatise - Softcover
Synopsis
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1912 Excerpt: ... diagram of sections proceed as follows: Take the girth of the outer curve 1 to 6 in the side elevation, and place it on the vertical line K L as shown by similar numbers, through which points, at right angles to K L, draw lines indefinitely. Measuring from the center line A E in the diagram of sections take the various distances to points 1,2,3,4,5 and 6 and place them on similar numbered lines in the pattern for top, measuring on either side of the center line K L. A line traced through points thus obtained will be the pattern for the top of the ventilator and the miter cut shown from 1 to 6 will give the true edge line of the upper curve of the lateral piece B in the side elevation. To obtain the pattern for the bottom of the ventilator, take the girth of the lower curve 19 24 in the side elevation and place it on the line M N as shown by similar numbers, through which draw the usual measuring lines. Measuring from the line A E in the diagram of sections, take the various distances to 19, 20, 21, 22, 23 and 24 and place them on similar lines in the pattern for the bottom, measuring on either side of the center line M N. A line traced through the various intersections will be the pattern for the bottom marked E in the diagram of sections and the miter cut 19 24 in the pattern for bottom will be the true edge line of the lower curve of the lateral piece marked D in the side elevation. To obtain the true lengths on the miter line 7 12 in the side elevation, take the distances from 7 to 8, 8 to 9, 9 to 10, 10 to 11 and 11 to 12 and place them on any horizontal line as a b, as shown from 7 to 8, 8 to 9, 9 to 10, 10 to 11 and 11 to 12. It will be noticed that the lengths are placed backward and forward over one another, so as to take up little space. At right ...
"synopsis" may belong to another edition of this title.
