In mechanical or shop drawing it is customary to give three views of the thing which is to be built, and of an ordinary piece of work the three views will be sufficient. However, if the thing is very complicated it may then be necessary to make more than the three views. But the three regular views, known as the plan, front elevation and end elevation, are the ones that are commonly presented. These are the regular views used throughout this text.
The plan of an object simply shows how it would appear if looked down upon directly from above. Of course it would be impossible to get in a position where you could see all of an article exactly as shown in the plan, for the plan represents it as seen in parallel lines, that is, as though you were looking straight down upon every part at the same time. All parts which would be in view from this position are indicated by solid black lines in the drawing; of course there would be many underneath and hidden parts to be shown by dotted lines.
By the front elevation we mean the representation of the article as seen from straight in front, when it is (sitting) on its natural base. The front elevation is seen at right angles to the plan; the hidden parts are represented in their proper positions by dotted lines.
By the end elevation we mean the appearance of the article from the right end, exactly at right angles to the plan and to the front elevation. Of course in the end elevation the black lines would represent the parts which would stand in plain view as seen from the end, and the dotted lines would represent the hidden or unseen parts in their proper positions. You will notice that this principle is true of each view. These three views of an object should be sufficient to enable one to form a clear idea of the full construction. Learn to study the drawings very carefully in order to get the desired information; this is exactly what every mechanic who works at any line of construction work must do. If you will provide yourself with the proper equipment and work out the following lessons in Mechanical Drawing you will then understand these principles pretty thoroughly. This is an important part of industrial work, for you should learn not only to read drawings, but to prepare simple working drawings for anything which you may desire to make. Throughout this book the photographs at the opening of each lesson will give you a clear idea of the appearance of the object presented and the working drawings will show you its exact construction.
The drawing outfit need not be expensive, but it should be good enough to enable you to do accurate work; you can make your own drawing board and T-square by following the instructions given in this text.
The following illustration shows rather a complete outfit, some of the articles may be omitted in your early work: