1. CNC
Machines
Computerize
d Numerical
Controlled
Machines

2. What is a CNC machine?In contrast to the conventional Lathe machines where operators give input and control
the working,CNC machine is a machine which does machining process with the help of
computerized control units which give it instructions regarding:
1. Tool Control:Tool and tool parameters
2. Units, incremental or absolute positioning
3. Feed rate and spindle speed
4. Coordinate System
5. CoolantControl: On/Off, Flood, Mist
6. Coordinates: X,Y,Z

3. CNC
Machines
Types
There are five different types of CNC machines gives as
follows:
1. CNC Lathe Machine
2. CNC Milling Machine
3. CNC Router Machine
4. CNC Laser Cutting Machine
5. CNC PlasmaCutting Machine

4. Working CNC working principle consists of following steps:
• Controlled by G and M codes.
• These are number values and co-ordinates.
• Each number or code is assigned to a particular
operation.
• Typed in manually to CAD/CAM by machine operators.
• G&M codes are automatically generated by the
computer software

5. Programmi
ng
Software
CNC machines use software to perform their
work .They can do both 2D and 3D processes on it. For 2D
works, we use G-Codes and M-codes.These codes are
specified to do certain operations on the lathe machines ,
These codes are arranged together to make a complete
program on the CNC machine,These programs then
guide the machine to perform the desired processes in an
orderly manner.

6. Programmi
ng Soft
wares
For 3D works, we use certain software’s like:
1. Master Cam
2. Dell-Cam
3. Pro E
The software Pro E can even perform processes in 4D.The
procedure is carried out at first we make a drawing on
CAD, convert it into CAM and then the machining is done
on the part being manufactured.

7. Types of
CNC
Control
Units
These are the major companies providing control units for
the CNC machines to be operated:
• SIEMENS
• MECH 3
• FANUC
• GSK
• Pentode

8. Advantages 1. High Repeatability and Precision e.g. Aircraft parts
2. Volume of production is very high
3. Complex contours/surfaces need to be machined. etc
4. Flexibility in job change, automatic tool settings, less
scrap
5. More safe, higher productivity, better quality
6. Less paper work, faster prototype production,
reduction in lead times

9. Disadvanta
ges:
1. Costly setup, skilled operators
2. Computers, programming knowledge required
3. Maintenance is difficult