Mechanical Drawing
Mechanical Drawing is known as scale drawing of a machine or architectural plan or the craft of drawing blueprints i.e. drafting. The variety of lines used in preparing a mechanical drawing is large, and each of them has its particular meaning. Boundary lines outline the shape of an object and its parts. Section lines are used to show intersections and the outlines of shapes within the boundary lines. The central axes of an object are represented by the center lines. Break lines are used to indicate that the entire object is not seen in the drawing. These, together with hidden lines and dimension lines, are used most frequently.
Correct design information and projection are the imperatives of a set of engineering drawings. The skill and dexterity shown by some persons in drawing more accurately, more quickly, or more neatly have recognized value in the preparation of such drawings. Equipment has been invented to facilitate the performance of the manual tasks. Most widely known are the T square, triangle and protractor. Bridge building begins long before ground is broken for the supports. The making of a bolt also starts well before the machinist sets an automatic machine to cut the thread into a piece of metal. Actually, for both projects, much planning and work have been completed before effort to undertake construction begins. In building a bridge, months of preliminary work are required before construction workers and tools meet on the job. Students wishing to become skilled drafters must practice certain standard exercises. There are many kinds of exercises that can be performed to increase speed and develop accuracy.
Mechanical drawings are widely used to create artwork for automotive design, architectural plans, engineering drawings, or electrical circuit diagrams. The introduction of the computer and accompanying drawing applications, such as Adobe Illustrator and Corel Draw (not to mention cad programs), have rendered skill with pen and pencil almost absolute.