Tool Types

Basically the tools can be classified as Generating tools and Forming tools.

Generating Tools

These tools are used to generate required profiles by manipulating the relative motions of the workpiece and the tool cutting edge. Thus the obtained contour of the workpiece would not be identical to the shape of the cutting tool edge. This is generally used for a majority of the general profiles required. The surface shown in Figure 4 is produced as a result of the primary motion of the workpiece as well as secondary (feed) motion of the cutting tool.

           Figure 4: Generating Tool

Forming is an alternate method of producing the required profiles, in which the shape of the cutting tool is impressed upon the workpiece as shown in Figure 5. The accuracy of the shape thus obtained is dependent upon the accuracy of the form of the tool used.

          (a) Form Cutting                                               (b) Angular Milling

          Figure 5: Forming Tools

However, many machine tool operations employ a combination of the above two processes.

Tools further are selected depending upon the metal removal rate (MRR) required and the type of operation used. The details of which shall be discussed further.