Student Workbook for Programming of CNC Machines. Ken Evans

      Ken Evans has held diverse machining and related jobs throughout his career and is currently a CNC Programmer at a prominent aerospace company. He learned the machinist trade in 1976 at Cessna Aircraft in Wichita, Kansas. Evans began his formal teaching career in 1984 at the T.H. Pickens Technical Center in Colorado, while working full-time as a CNC machinist and quality control inspector.

      From 1991 to 2010, he served as a Machine Tool Technology instructor at Davis Applied Technology College in Kaysville, Utah, teaching foundational through advanced-level courses in the machining curriculum, including Mastercam CAD/CAM classes for students, educators, and private industry. He also was designated a certified Project Lead the Way, Computer Integrated Manufacturing (CIM) instructor. From 1997 to 2003, Ken worked for a local machine tool distributor in Salt Lake City as a MAZAK certified Training and Applications Specialist and one of the nation’s first Mazatrol Conversational Programming instructors.

      Ken loves the outdoors; he enjoys gardening, mountain biking, and golf.

      Preface

      Many textbooks written on the subject of CNC programming include a multitude of practical examples; however, very few include enough practice exercises for readers to verify their understanding. This edition of Student Workbook to Accompany Programming of CNC Machines provides many practical exercises designed to verify comprehension of CNC programming. Although this workbook is written as a companion to Programming of CNC Machines, Fourth Edition, it may be used to confirm anyone’s knowledge of CNC programming. There are many ways to program a part in order to get the accurate results. The proven method offered in the answer key is consistent with the companion text. Most important, the part is produced to specifications, both safely and efficiently.

      It is possible for someone to program a CNC machine without actual machining experience. Still, the result will be better if a practical background exists. Feeds and speeds, tool selection, and work holding methods are very hard to learn from a book. Practical experience has been proven to be the best teacher. It is also a plus to have a thorough understanding of shop mathematics. A student who has been taught the basic fundamentals in these matters, beforehand, will have the most success writing CNC programs in the long term.

      Units 1 through 4 of this workbook should be used to verify that you have learned the basic skills necessary to write CNC programs, line-by-line, to make a variety of workpieces. The answer key for each unit provides answers/solutions to verify correct programming. Try to complete as many questions and examples as possible without using the answer key. It would be better to use the text (Programming of CNC Machines, Fourth Edition) to look up the required information, rather than go directly to the answers. The text is a reference tool; just like your machinist tools, it was designed to help you get the job done. Whenever it is possible, consult with your trainer for additional ideas or methods to evaluate your work.

      STUDENT WORKBOOK

      to accompany

      PROGRAMMING OF

      CNC MACHINES

      Fourth Edition

      Unit 1: CNC Basics

      Process Planning

      Any time a new part is considered for manufacture, it is necessary to have a logical plan in order to machine it efficiently. The following is an explanation of the exercise requirement: Three Process Planning Sheets are provided on the following pages for operations (Chart 1-1), setup (Chart 1-2), and quality control (Chart 1-3). Copy as many as you need. Later in the workbook, CNC Programming Sheets are included for the units covering Turning Center Programming and Machining Center Programming. For a detailed description of the use of these documents, please refer to Programming of CNC Machines, Fourth Edition, Part 1, CNC Basics. You will also find in the units covering Turning Centers and Machining Centers a list of cutting tools that can be used for preparing the Process Planning Sheets.

      Use the Operation Sheet (Chart 1-1) to identify each individual operation and the machines necessary to complete the part in the blueprints that follow.

      Use the CNC Setup Sheet (Chart 1-2) to identify work holding, cutting tools, work piece coordinate zero locations, and any other pertinent information needed to complete the part setup for these blueprints. Refer to the tool lists provided in Unit 3 (CNC Turning Center Programming) and Unit 4 (CNC Machining Center Programming) to choose the appropriate tools.

      Use the Quality Control Check Sheet (Chart 1-3) to list 100% of the dimensional data needed to verify that the parts are made to specification, starting with the blueprints in Figures 1-1 and 1-2.