Cnc Machining Handbook: Building, Programming, and Implementation

361 Pages·2010·6.68 MB·English

by  Alan Overby

CNC Machining Handbook
About the Author
Alan Overby received a B.S. in Electrical Engineering from Arizona State
University. He has always had a hobbyist interest in CNC technology, and has
owned, programmed, and operated several CNC routers and engraving machines
on a professional level within the signage industry. Mr. Overby was co-owner of
Custom CNC, Inc., a company that provided new and replacement controller
systems to both individuals and original equipment manufacturers.
CNC Machining Handbook
Building, Programming, and Implementation
Alan Overby
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ISBN: 978-0-07162302-5
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Contents
Preface
Part I The Physical Architecture
1 CNC Machines
Common CNC Applications
2 Guide Systems
Round Rail
Profile Rail
V-Style Roller
Hybrid Roller Guides
3 Transmission Systems
Screw and Nut
Lead Screw and Nut
Ball Screws
Rotating Nut
Rack and Pinion
Reducers
Timing Belt and Pulleys
Constructing a Pulley-Reduction Unit
4 Motors
Stepper Motors
Servo Motors
Stepper versus Servo: Pros and Cons
Encoders
Part II The CNC Controller
5 Controller Hardware
Enclosure
Breakout Board
Drives
Power Supply
Adjunct Devices for Controller Hardware
Pendant
Wiring
6 Control Software
Mach3 Control Software
Enhanced Machine Controller, Version 2 (EMC2)
A Foreword on Computer Operating Systems and Applications
G-Code Editors
G Code
Part III Application Software
7 The Cartesian Coordinate System
The Table or Mill Topology
Lathe/Rotary Topology
8 CAD and Graphics
Raster to Vector Conversion Utilities
Difference between 2D and 3D
Listing of CAD Vendors
Graphics Programs
9 CAM Software
Understanding and Using CAM
Generalized Milling Options
CAD and CAM Combination Software
Part IV Building or Buying a CNC Machine
10 Choosing a Ready-Made CNC System
Router/Plasma Table
Mills and Lathes
Do-It-Yourself (DIY)
Vendor Listing
11 Building Your Own CNC Plasma Table
Part V Appendices
A Project Implementation and Examples
Examples of Items that Can Be Produced on a CNC Router
Unlimited Possibilities
Programming Examples
B Programming Examples in G Code
Example 1
Example 2
C Engineering Process of Selecting a Ball Screw
D NEMA Motor Mounting Templates
Index
Preface
Using CNC, whether on a professional or hobbyist level, is not only an exciting
process to be involved in but is also the direction manufacturing is heading.
There are a great many facets and stages involved in the end-to-end process of
understanding and implementing CNC, and, although there have been several
books published on specific aspects or topics (such as G-code programming,
building a CNC machine, etc.), there have been no books written that guide the
reader through the overall process, that is, until now. It is not the intent of this
book to replace any previously written information on this topic nor to delve
into any particular area. However, by the time readers finish reading this book,
they will have a solid understanding of the entire CNC process from a top-down
end-to-end perspective.
More specifically, this book is intended for the following audiences:
• Academic: This book will provide the instructor and students a very
informative introduction into applied CNC, the various machines, and
their uses, along with the necessary tools used in the process.
• Business owner: The aspect of moving a small-to medium-sized
business, or even a startup company, from a manually concentric
manufacturing process into the accuracy and repeatability of what CNC
has to offer, can be a daunting task. This book guides business owners
in the proper direction to help them understand and decide the ins and
outs of automating their manufacturing process. Furthermore, also
discussed will be what to look forward to when growing future CNC-
based operations.
• Hobbyist: There are a great number of individuals interested in the
understanding and technical aspects of CNC, but are not exactly sure
where to begin—what is absolutely required for the application at hand
from both a hardware and software perspective and what is not. There
are many free and low-cost software options to choose from that are
listed for the reader to appropriately determine what is needed for their
particular application.
• Readers looking for an industry guide: This book is also intended to be