Industrial Applications of
Computers
Computer Aided Manufacturing
(CAM)
Computer Numerical Control
(CNC)
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CAM/DNC/CNC

Definitions:
 CAM:
Computer Aided Manufacturing. A computercontrolled manufacturing process. A system using a
computer to control a process. Systems range from
three-axis NC mills to full factory automation
 DNC: Direct Numerical Control
 CNC: Computer Numerical Control. The use of a
dedicated computer as a control system for an NC
machine
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CAD/CAM integration
 The
CAD model data generated during the design
process can be utilized further by the Computer Aided
Manufacturing process. A good CAD/CAM system
eliminates the need to manually calculate tangencies
or to do the trigonometry required to calculate tool
paths, saving valuable programming time. It also
provides a consistent finish and predictable results.
http://www.engineeringzones.com/cam_nc.htm
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How to integrate CAD/CAM (1)
CAD Program
DXF File
CAM Program
NC File
CNC Program
Computer Aided
Design
Computer Aided
Manufacturing
Computer
Numerical Control
 Geometry
 Program
 Produce
of part is
created (3D or 2D;
surface or solid)
the part
with G/M-codes
•Milling
•Lathe
•Electric
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the part
Discharge
How to integrate CAD/CAM (2)
Start
Plan
Process
Planning
Create CAD
Drawing
Convert drawing
to DXF
CAD
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Load DXF
file
List NC file
(Optional)
Verify NC
Program
Select a layer
Save NC File
Mill Part
CNC
Select a milling
operation
Select another
layer?
Enter cutting
Parameters
Generate tool
path
CAM
End
Machining Operations
Milling
Turning
Electrical
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Discharge Machining (EDM)
CNC Machining Centers
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CNC Lathe
http://customer.manufacture.com.tw/~likon/lnc.htm
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CNC Lathe
Driven tools for complex drilling and milling operations as well as a
complete counter spindle for machining the work pieces counter
sides.
Price: from 215,610 Euro
http://www.gildemeister.com/gb/dreh.asp?ID=9
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Application Examples (Turning)
http://www.gildemeister.com/gb/3_3_2_22.htm
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EDM



The generic term EDM (Electrical Discharge Machining) can be
applied to any machining process that uses an electrode to
remove metal, or any other conductive material, from a work
piece by generating sparks between conducting surfaces.
This is being performed in a dielectric fluid to prevent premature
spark discharge.
Wire EDM uses a traveling wire electrode that passes through
the work piece, the wire is, at all times, monitored by the
machine’s internal computer system. This process can be seen
as a very high precision band saw that can hold tolerances of +/.0002.
http://mercatech.com/
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Distinction
Absolute/Incremental
 Absolute

measuring
 Incremental
one absolute coordinate
system using (XYZ) location
measuring

from point to point

–3 left and 2 up
P
Q

P (-1/1); Q (2/-1)
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 x=
-3 / y= 2
Variables in Machining Process
 Cutting
tools: type, size, and tool material lead
to different feed rates and spindle speeds
 Materials: lead to different feed rates and
spindle speeds
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Variables in Machining Process
Work
Material
Cutting Speeds in SFPM
End Mills
Fly cutters
HSS
Carbide
HSS Carbide HSS Carbide
Aluminum
150
300
600
1200
125
Cast iron
Soft
Hard
90
50
180
100
450
400
900
800
60
120
400
800
Stainless
Steel
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Drills
Reamers
HSS
Carbide
250
60
120
90
70
180
140
40
35
80
70
70
140
35
70
Milling Tools and Tool Inserts
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NC Programming Codes (G/M)
- A Selection
M-Codes (Miscellaneous
Codes)
 M00 Pause
 M02 End of Program
 M03 Spindle Motor on
 M05 Spindle Motor off
 M06 Tool Change
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
G-Codes
 G00 Rapid traverse positioning
 G01 Feedrate Movement
Linear
 G02 Feedrate Movement
Circular clockwise
 G03 Feedrate Movement
Circular counterclockwise
 G90 Absolute Coordinates
 G91 Incremental Coordinates
Milling Operations

Most of the following operations have special G-codes:

Facing: removes material across the top surface
Contouring: removes material to a specified depth along a CAD
geometry
Drilling: uses points identified on a CAD layer to drill holes to a
specified depth
Pocketing: removes all material within the outline of a CAD
geometry
Surface of Revolution: removes all material within a surface
generated by revolving geometry about the X or Y axis




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Leading CAM Software
 Mastercam:
http://www.mastercam.com/mainFrame4.htm
 Unigraphics: http://www.ugsolutions.com/products/unigraphics/
 SmartCAM: http://www.sdrc.com/support/smartcam/support.shtml
 EZ-CAM: http://ezcam.com/support.htm
 Other Links:
http://msnhomepages.talkcity.com/CerfSt/cadcamworld/navig.htm

Pro Engineer (http://www.ptc.com/)
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