Engineering Design Graphics: Sketching, Modeling, and Visualization, 2nd Edition

CHAPTER 8

WORKING DRAWINGS

INTRODUCTION

At the beginning of any project, there is no guarantee that a design will actually be executed. If a project is put out to bid, for example, only one of several competing preliminary designs will be selected. Even then, funding for the project may fall through. Similarly, for a company engaged in both research and development, management may decide to abandon the development of a new product.

Once the decision is made to build, however, the existing preliminary design must be further developed and detailed for production. The term working drawing is used to describe the complete set of drawing information needed for the manufacture and assembly of a product based on its design.

As discussed in the previous chapter, commercial products are almost always assemblies comprising several different parts. Perhaps the most recognizable element of a working drawing set is the assembly drawing. The purpose of the assembly drawing is to show how the different components fit together to form the product. An example of an assembly drawing is shown in Figure 8-1 on page 248.

An essential element of a working drawing is the parts list, or bill of materials (abbreviated BOM). The purpose of the BOM is to identify all parts, both standard and nonstandard, used in an assembly. The BOM for the assembly shown in Figure 8-1 is located in the upper-right corner ...