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 VII.

Chapter 6296 wordsPublic domain

EXAMPLES IN BOLTS, NUTS AND POLYGONS.

To represent the thread of a small screw 112

A bolt with a hexagon head 113

United States standard sizes for forged or unfinished bolts and nuts 116

The basis of the Franklin Institute or United States standard for bolts and nuts; hexagonal or hexagon heads of bolts 118

Comparison of hexagon and square heads of bolts; chamfers 120

Without chamfer; best plan for view of both square and hexagon heads 123

Drawing different views of hexagon heads 125

To draw a square-headed bolt; to draw the end view of a hexagon head 125

Use of the triangle to divide circles 129

Scales giving the length of the sides of polygons 135

To find what a square body which measures one inch on each side measures across the corners; to find what diameter a cylindrical piece of wood must be turned to which is to be squared, and each side of which square must measure an inch 136

To find a radius across corners of a hexagon or a six sided figure, the length of a side being an inch 138

To draw a stud 142

To pencil in a cap nut; pencilling for a link having the hubs on one side only 145

Link with hubs on both sides; pencil lines for a double eye or a knuckle joint 146

Double eye or knuckle joint with an offset; a connecting rod end 147

A rod end with a round stem 148

A bolt with a square under the head 149

Example in which the corner where the round stem meets the square under the head is sharp; a centre punch giving an example in which the flat sides gradually run out upon a circle, the edges forming curves 150