Cyclopedia of Mechanical Engineering: A General Reference Work on Machine Shop Practice, Tool Making, Forging, Pattern Making, Foundry, Work, Metallurgy, Steam Boilers and Engines, Gas Producers, Gas Engines, Automobiles, Elevators, Refrigeration, Sheet Metal Work, Mechanical Drawing, Machine Design, Etc, Volume 7Howard Monroe Raymond American technical society, 1908 |
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angle arms axis bearing belt bending bending moment bracket calculation cast iron center line centrifugal force circle coefficient of friction cotter cylinder detail diameter dimensions distance draftsman drawing drawn driving drum edge elevation equal equation fastening fiber stress figure finished flange friction gear inches ground line Hence hole horizontal horse-power layout length load lubrication Machine Design machinery material Mechanical Engineers metal method necessary paper pencil piece pinion pipe piston plane Plate pounds practical pressure prism produce projection proportions pulley radius revolutions per minute rope scale SCHOOL OF CORRESPONDENCE screw shade lines shaft shearing shearing stress shop drawing shown in Fig side sketch speed spur gears square inch standard steel strength stud student surface T-square taper teeth tensile stress tension theoretical thickness thread tion tooth torsional triangle usually vertical weight width worm gear
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Page 17 - TRIANGLES. is hung up when not in use ; when allowed to lie on the drawing board with a pencil or an eraser under one corner it will become warped in a short time, especially if the room is hot or the sun happens to strike the triangle. Triangles are made in various sizes, and many draftsmen have several constantly on hand. A triangle from 6 to 8 inches on a side will be found convenient for most work, although there are many cases where a small triangle measuring about 4 inches on a side will be...
Page 53 - Paper should be laid out at the same size as the plates in Parts I and II. The center lines and border lines should also be drawn as described. First draw two ground lines across the sheet, 3 inches below the upper border line and 3 inches above' the lower border line. The first problem on each ground line is to be placed 1 inch from the left border line; and spaces of about 1 inch should be left between the figures. Isolated points are indicated by a small cross X, and projections of lines are to...
Page 52 - No. 2, and the elevation is found by projecting up to the same heights as shown in the proceeding elevation. This principle may be applied to any solid, whether bounded by plane surfaces or curved. This principle as far as it relates to heights, is the same that was used for profile views. An end view is sometimes necessary before the plan or elevation of an object can be drawn. Suppose that in Fig. 18 we wish to draw the plan and elevation of a triangular prism 3" long, the end of which is an equilateral...
Page 53 - We are able to draw the plan at once, because the width will be 1\ inches, and the top edge will be projected half way between the other two. The length of the prism will also be shown. Before we can draw the elevation, we must find the height of the top edge. This height, however, must be equal to the altitude of the triangle forming the end of the prism. All that is necessary, then, is to construct an equilateral triangle 1£" on each side, and measure its altitude.
Page 94 - ... that distance represent one foot, this distance is then divided into twelve parts and each one of these parts represents an inch; then if half and quarter inches are required these twelfths are subdivided into halves, quarters, etc., until the subdivisions become so small that they cannot be used. We now have a scale which represents the common foot rule with its subdivisions into inches and fractions; but our new foot is smaller than the ordinary distance which we call a foot, and of course...
Page 103 - The length of time to which a print should be exposed to the light depends upon the quality and freshness of the paper, the chemicals used and the brightness of the light. Some paper is prepared so that an exposure of one minute, or even less, in bright sunlight, will give a good print and the time ranges from this to twenty minutes or more, according to the proportions of the various chemicals in the coating. If the full strength of the sunlight does not strike the paper, as, for instance, if clouds...
Page 5 - ... on the Designing, Constructing, and Use of Tools, Fixtures and Devices, together with the manner in which they should be used in the Power Press, for the cheap and rapid...
Page 100 - After a little practice, however, he will find that the tracing cloth is very satisfactory and that a good drawing can be made on it quite as easily as on paper. The necessity for making erasures should be avoided, as far as possible, but when an erasure must be made a good ink rubber or typewriter eraser may be used. If the...
Page 22 - Fig. 12. Fig. 13. line DA may be drawn, and by sliding the triangle along the edge of the T-square to the position F the line BC may be drawn by using the same edge. These positions are shown dotted in Fig. 15. If the rectangle is to be placed in some other position on the drawing board, as shown in Fig.
Page 141 - Completeness. A detail is completely dimensioned when it shows all the figures necessary for the workman. Anything short of this is incompleteness. As modern shops hold the draftsman solely responsible for the design, the mechanic is not allowed to modify it by filling in any omitted dimensions. The only way to be sure that all the dimensions are on is to systematically go all round a piece inside and out, according to the method suggested under the paragraph on "System.