2.1 Types of Drawings
Drawings that are used in a shop to produce objects are known as working drawings. Working drawings focus on providing essential information needed by the craftsmen who actually produce the parts in the shop. Like mechanical drawings, working drawings are created using computer-aided drafting software programs. Copies of these drawings made on the computer are called prints. In the past, prints were produced using a process that resulted in white lines on a blue background. Today, prints are copied on white paper, but are still sometimes referred to as “blueprints.” The proper term, however, is merely “prints.” Working drawings are produced in two forms, the assembly drawing and the detail drawing.
2.1.1 Assembly Drawings
An assembly drawing shows the object to be made as it would appear in a fully assembled, ready to use form. Important location dimensions and overall size dimensions are given on the assembly drawing. However, not all the dimensions that are required to make each piece in the assembly are shown on the assembly drawing.
An assembly drawing shows the object to be made as it would appear in a fully assembled, ready to use form. Important location dimensions and overall size dimensions are given on the assembly drawing. However, not all the dimensions that are required to make each piece in the assembly are shown on the assembly drawing.
2.1.2 Detail Drawings
Individual detail drawings are made of each different part in the assembly. These drawings are typically made on separate sheets, however, multiple detail drawings may be made on one large print. Every view required to make a part is shown on the detail drawing, along with every dimension required to produce the part.
To be able to read a print, you must understand the concept of orthographic projection. Almost all assembly and detail drawings are made using orthographic projection. Understanding how a drawing is made helps a person find various areas, lines, holes, welds, and other details on a drawing. This knowledge also helps in finding the sizes of parts on a detail drawing or the type of weld to make and where to place it.