Computer-Aided Manufacturing

Computer-Aided Manufacturing (CAM) is an important subject in all the universities and polytechnics. A large number of books in this area are also available. However, since the technology is advancing with a fast pace, these books are generally devoid of any discussion on latest technology, and at the same time, full of outdated contents. For example, many of these discuss APT language in detail in the context of CNC programming. The reality is that no CNC machine in the world accepts an APT program! Moreover, for the purpose of simplifying programming, several complex canned cycles (a canned cycle is like a subroutine which performs complex calculations, and automatically generates a series of the required toolpaths, based on the specified data, to accomplish the desired task) are available on modern CNC machines. Also, gone are the days when a lathe was used only for turning applications. Modern lathes have provision also for certain milling-type operations, using live tools (a live tool has an independent motor attached to it, which makes it rotate for drilling/tapping/milling operations, while the main spindle, holding the workpiece, remains stationary). For example, among several applications, live tools can machine a cylindrical cam, mill a hexagonal bolt head, drill off-center holes on the PCD of a flange etc., all on a modern lathe. The existing textbooks have absolutely no clue about all this. As a result, students generally do not learn anything which has a practical utility. The present book is specifically aimed at filling the gap between what is taught in the class and what is required by industry.

In any manufacturing industry, despite all automations and other fancy things, the actual work is done by CNC machines. Therefore, these must be used to their full potential, in the most efficient manner. This makes CNC programming the most important aspect of computer-aided manufacturing. Therefore, this has been the main emphasis in this book.

Though any machine tool can be designed to have a CNC control, the most common ones are lathes and milling machines. Milling machines are often used for profile machining, involving simultaneous tool movement along the three orthogonal axes. Manual programming in such a case is too complicated, often to the extent of being practically impossible. This necessitates the use of commercial CAM softwares for generating toolpaths. Once a CAM software is available, people tend to use it even for simple applications where manual programming can easily do the job. As a result, most people do not bother to learn manual programming on milling machines, beyond a certain basic level. Therefore, this book has purposefully concentrated on manual programming of lathes.

Learning becomes a fun if one starts with a small first step, and proceeds further to learn more complex things step-by-step. This has been the motivation for presenting the present book. The author has made good use of his 30+ years of teaching experience to explain the concepts in a student-friendly manner. The book is designed in a textbook style, to be read from cover to cover.

The present book avoids detailed discussion on macro programming. Interested readers may refer to the macro-programming book by the author, published by McGraw-Hill.

The description in the book is based on Fanuc 0i TC control. There can be some minor but usually insignificant differences in other control versions/models of Fanuc..

The author is of the opinion that if the book is read, starting from beginning, without skipping the essentials (one may skip certain optional features, such as the discussion on live tools, if the machine is not equipped with it), it would be an enjoyable learning experience, that too without any additional help, in the form of another book or an instructor.