What is NC Machine?
NC stands for Numerical Control, and an NC machine is a type
of machine tool that uses programmed commands to operate the tool. NC machines
were first introduced in the 1940s and have been widely used in manufacturing
and industry ever since.
In an NC machine, the operator enters commands into a
computer program, which then controls the machine's movements. These commands
can specify the exact position and movement of the tool, as well as the speed
and feed rate. The computer program can also include other instructions, such
as tool changes or coolant flow.
NC machines have many advantages over traditional machine
tools. They allow for much greater precision and accuracy, as well as faster
and more efficient production. They also reduce the need for skilled operators,
as the computer program can take care of many of the tasks that would
traditionally be done by hand.
There are many different types of NC machines, including
milling machines, lathes, grinders, and routers. Each type of machine is designed
for a specific set of tasks and can be programmed accordingly. Overall, NC
machines are a vital component of modern manufacturing and have revolutionized
the way that products are made.
Parts of Numeric Control Machine:
The major components of a numerical control (NC) machine include:
Panel: This is the interface between the operator and the machine, where
the operator can input commands, set parameters, and monitor the machine's
Bed: This is the base on which all other machine components are mounted.
This is the rotating component of the machine that holds the cutting tool
NC machines typically have at least three axes (X, Y, and Z) that allow
for movement in different directions. Additional axes, such as A, B, or C,
may also be present on some machines.
Motors: These motors provide the power to move the machine along its
Devices: These devices provide feedback to the control system on the
position and motion of the machine, allowing for precise control and
Tools: These are the tools used to cut, drill, or shape the workpiece.
System: This system is used to lubricate and cool the cutting tools,
reducing wear and tear and improving the quality of the finished product.
Devices: These devices hold the workpiece securely in place during
Overall, each component of an NC machine plays a crucial
role in its operation and performance, enabling high precision and accuracy in
Classification of NC Machine:
Numerical Control (NC) machines can be classified into
several categories based on their configuration, size, and function. Here are
some common classifications of NC machines:
on the number of axes: NC machines can be classified as 2-axis, 3-axis,
4-axis, 5-axis, or more, depending on the number of axes of movement they
possess. The number of axes determines the degree of freedom that the
machine can achieve and, hence, its versatility and complexity.
on the type of motion: NC machines can be classified as linear or
circular, depending on the type of motion they produce. Linear NC machines
are designed for straight-line movements in the X, Y, and Z axes, whereas
circular NC machines are designed for circular or curved motions.
on the type of machining operation: NC machines can be classified as
milling machines, lathes, drilling machines, grinding machines, or other
specialized machines, depending on the type of machining operation they
on the level of automation: NC machines can be classified as fully
automated or semi-automated, depending on the level of human intervention
required in the operation of the machine.
on the size: NC machines can be classified based on their size, such as
small, medium, or large, depending on the size of the workpiece they can
Overall, the classification of NC machines allows for a
better understanding of their capabilities and limitations, which in turn helps
in selecting the most appropriate machine for a particular manufacturing task.
Basic Components of NC Machine
The basic components of a Numerical Control (NC) machine are
Input: The program input is where the NC program is entered into the
machine. This can be done via various methods, such as manual data entry
or data transfer from a computer.
The controller is the brain of the NC machine, responsible for
interpreting the NC program and converting it into commands that control
the machine's motion. The controller typically consists of a computer,
software, and hardware components such as servo motors and amplifiers.
System: The drive system includes the motors, gears, and other mechanical
components that drive the motion of the cutting tool along the NC
Tool: The machine tool is the physical structure of the NC machine that
holds the workpiece and performs the cutting operations. The machine tool
can include various components such as spindles, chucks, and tool
System: The feedback system consists of sensors that provide information
on the machine's position, velocity, and other parameters. This feedback
is used by the controller to ensure accurate positioning and motion
Interface: The operator interface is where the operator interacts with the
NC machine, providing input and monitoring the machine's operation. This
interface can include displays, buttons, and other input devices.
Supply: The power supply provides the energy needed to drive the machine's
motors and other electrical components.
Overall, these components work together to allow the NC machine to accurately and precisely control the motion of the cutting tool and perform complex machining operations.
NC Machine Working Principle:
The working principle of a Numerical Control (NC) machine
involves the use of a computerized control system to guide the machine's
movements and perform specific machining operations. Here's a general overview
of the NC machine working principle:
The NC machine operator creates a computer program that specifies the
desired machining operations, including tool path, cutting speed, and feed
Input: The computer program is input into the machine's control system
using a standard data input device, such as a USB drive, network
connection, or direct data transfer.
System: The control system receives the data input and translates the
instructions into machine movements. The control system includes a
processor, memory, and input/output devices, such as a display screen,
keyboard, and control panel.
Motors: The control system sends signals to the servo motors that drive
the machine's movement along its various axes. The servo motors are
precise, high-torque motors that can move the machine's components with
high accuracy and repeatability.
Devices: The machine's feedback devices, such as encoders or linear
scales, provide position and motion data to the control system, allowing
it to monitor and adjust the machine's movements in real-time.
Operation: The machine's cutting tool is positioned and oriented according
to the programmed instructions, and the cutting operation is initiated.
The control system continuously monitors the machine's movements and
adjusts the cutting parameters as necessary to ensure accuracy and
Removal: After the cutting operation is complete, the workpiece is removed
from the machine, and the process may be repeated for additional
Overall, the NC machine working principle relies on the
precise control of the machine's movements and cutting parameters to achieve
accurate and consistent machining results. The computerized control system
enables high automation, precision, and flexibility, making NC machines ideal
for a wide range of manufacturing applications.
Advantages and Disadvantages of NC Machine:
Numerical Control (NC) machines offer several advantages and
disadvantages. Here are some common advantages and disadvantages of NC
NC machines are capable of producing highly precise and accurate
workpieces, with tolerances as small as a few microns.
NC machines can be programmed to perform a wide range of machining
operations, making them versatile and flexible for various manufacturing
NC machines are highly automated, reducing the need for human intervention
and minimizing errors.
NC machines can perform machining operations quickly and efficiently,
resulting in higher productivity and reduced production time.
NC machines can produce consistent results from one workpiece to another,
ensuring uniform quality and reducing the likelihood of defects.
NC machines can be expensive to purchase and maintain, requiring
specialized training and equipment.
Programming NC machines requires specialized skills and knowledge, making
it challenging for small businesses or individuals to operate.
NC machines require regular maintenance and upkeep to ensure proper
functioning, which can be time-consuming and costly.
The high degree of automation and precision of NC machines can make them
complex and challenging to operate, requiring skilled technicians to
maintain and repair them.
NC machines may not be suitable for all types of machining operations,
materials, or workpiece sizes, limiting their range of applications.
Overall, the advantages and disadvantages of NC machines
depend on the specific manufacturing task and the resources available. While
they offer many benefits, the cost and complexity of NC machines may be
prohibitive for some businesses or individuals.
Difference Between NC and CNC Machines:
The main difference between Numerical Control (NC) machines
and Computer Numerical Control (CNC) machines is the level of automation and
programming sophistication. Here are the key differences between NC and CNC
System: NC machines use a pre-programmed set of instructions, while CNC
machines use a computerized control system to execute the machining
NC machines use G-code or other simple programming languages to specify
the machining instructions, while CNC machines use advanced programming
languages, such as ISO, APT, or G-code.
NC machines are partially automated, with some manual operations required,
while CNC machines are fully automated, with little or no manual
CNC machines are generally more precise and accurate than NC machines, as
the computerized control system can make minute adjustments to the
machining parameters in real-time.
CNC machines are more flexible than NC machines, as they can be programmed
to perform a wide range of machining operations, while NC machines are
limited to a set of pre-programmed instructions.
CNC machines are more complex than NC machines, requiring specialized
programming, maintenance, and operator training.
CNC machines are generally more expensive than NC machines, due to the
added automation and programming sophistication.
Overall, CNC machines offer greater precision, flexibility,
and automation than NC machines, but also require more specialized training and
expertise. The choice between NC and CNC machines depends on the specific
manufacturing task, budget, and resources available.
Application of NC Machine:
Numerical Control (NC) machines are used in a wide range of
manufacturing industries and applications, including:
NC machines are used to produce complex aircraft parts, such as turbine
blades and engine components, with high precision and accuracy.
NC machines are used to produce automotive components, such as engine
blocks, transmissions, and brake parts, with high efficiency and
NC machines are used to produce electronic components, such as circuit
boards and semiconductor components, with high precision and
NC machines are used to produce medical devices, such as surgical
instruments, implants, and prosthetics, with high accuracy and
and Die Making: NC machines are used to produce molds and dies for various
manufacturing processes, such as injection molding and stamping, with high
precision and durability.
NC machines are used to produce custom furniture, cabinetry, and other
wood products, with high precision and detail.
NC machines are used in metalworking processes such as milling, turning,
drilling, and grinding, with high precision and efficiency.
Overall, NC machines are widely used in manufacturing
applications where precision, accuracy, and efficiency are critical. Their
versatility and flexibility make them ideal for a wide range of industries and
Steps For Creation of Program For NC Machine:
Creating a program for Numerical Control (NC) machines
involves the following steps:
The first step is to design the workpiece to be machined using
Computer-Aided Design (CAD) software. The design must be precise, with the
required dimensions, tolerances, and specifications.
Selection: Once the design is finalized, the next step is to select the
appropriate cutting tools for the machining operation. The tools should be
suitable for the material being machined, and capable of achieving the
desired surface finish and accuracy.
Programming: The next step is to create a Computer-Aided Manufacturing
(CAM) program using CAM software. This involves specifying the tool path,
cutting parameters, feed rates, and other machining parameters. The CAM
program must be optimized for the specific machining operation and
After creating the CAM program, it needs to be post-processed to generate
the NC code that will be used to control the machine. Post-processing
involves converting the CAM program into machine-specific code, such as
G-code, that can be understood by the NC machine.
and Verification: Once the NC code is generated, it needs to be
transferred to the NC machine using a suitable data transfer method. The
NC code should be verified for accuracy and correctness using simulation
software or other verification tools.
Setup: Once the NC code is loaded onto the NC machine, the machine needs
to be set up for the machining operation. This involves installing the
cutting tools, workpiece, and fixtures, and configuring the machine
settings, such as spindle speed and feed rate.
Finally, the machining operation can be executed by running the NC program
on the machine. The machine will follow the specified tool path, cutting
parameters, and other instructions to produce the workpiece as per the
Overall, creating a program for an NC machine involves a
series of steps that require specialized skills, knowledge, and software tools.
It is critical to ensure that each step is executed accurately and correctly to
produce high-quality workpieces.
Types of NC Systems
There are mainly two types of Numerical Control (NC)
or Absolute NC System: In this type of NC system, the machine is
programmed to move from one point to another in a straight line, stopping
at each point to perform the machining operation. The machining operations
are performed at fixed points, and the machine does not perform any
interpolation or contouring. Point-to-point NC systems are simple and easy
to program, but they are limited in their capabilities.
Path or Contouring NC System: In this type of NC system, the machine is
programmed to follow a continuous path or contour, performing the
machining operation as it moves along the path. The machine is capable of
performing interpolation and contouring, allowing it to produce complex
shapes and curves. Continuous path NC systems are more versatile and
flexible than point-to-point NC systems, but they are also more complex
and require more advanced programming skills.
In addition to these two basic types of NC systems, there
are also various subtypes and variations, such as:
NC systems: These systems are capable of controlling multiple axes of
motion, such as X, Y, Z, and rotary axes, allowing for more complex and
precise machining operations.
control NC systems: These systems use sensors and feedback mechanisms to
monitor and adjust the machining parameters in real-time, improving
accuracy and efficiency.
numerical control (DNC) systems: These systems use a central computer to
control multiple NC machines, allowing for centralized programming and
architecture NC systems: These systems are designed to be more flexible
and customizable, allowing for easier integration with other software and
Overall, the type of NC system chosen will depend on the
specific manufacturing requirements and the capabilities of the machine and
NC Coordinate System
The NC coordinate system, also known as the machine
coordinate system, is a Cartesian coordinate system used by Numerical Control
(NC) machines to control the motion of the cutting tools during machining
operations. The NC coordinate system is relative to the machine's physical
structure, and its origin is usually located at one corner of the machine's
work table or chuck.
The NC coordinate system has three axes of motion:
The X-axis is the horizontal axis that runs from left to right when facing
The Y-axis is the vertical axis that runs from front to back when facing
The Z-axis is the vertical axis that runs up and down.
The NC coordinate system can be defined in various ways, but
the most common method is to set the origin at the machine's home position and
define the positive direction of each axis based on the machine's physical
structure. For example, the positive X-axis direction may be defined as moving
from left to right, while the positive Y-axis direction may be defined as
moving from front to back.
Once the NC coordinate system is established, the NC machine can use it to move the cutting tool to the desired position and perform the machining operation. The NC program specifies the desired position in terms of the NC coordinate system, and the machine's controller converts these coordinates into motor commands that move the tool along the appropriate axis.