Mechanical Drawing Self-Taught Comprising instructions in the selection and preparation of drawing instruments, elementary instruction in practical mechanical drawing; together with examples in simple geometry and elementary mechanism, including screw threads, gear wheels, mechanical motions, engines and boilers

CHAPTER VIII.

Chapter 7115 wordsPublic domain

SCREW THREADS AND SPIRALS.

Screw threads for small bolts with the angles of the thread drawn in, and the method of doing this 152

A double thread; a round top and bottom thread such as the Whitworth thread; a left hand thread; to draw screw threads of a large diameter 156

Drawing the curves for screw threads 157

To draw the United States standard thread 160

To draw a square thread 162

Form of template for drawing the curves of threads 165

To show the thread depth in a top or end view of a nut; to draw a spiral spring 166

To obtain an accurate division of the lines that divide the pitch 167