Mechanical Component Tolerance

What is CNC?
CNC (Computer Numerical Control) is a system that controls the functions of a machine
tool using coded instructions processed by a computer. It is an advanced version of NC (Numerical Control), where a dedicated stored-program computer performs some or all of the control functions based on the program stored in its memory. In a CNC system:

 The program is entered once and stored in the computer’s memory.

 The part program, containing instructions, is fed into the computer.

 These instructions are interpreted by the controller and converted into signals.

 The signals activate the machine tool to perform the required operations. Stages in Producing a Component Using CNC:

1. Part Program Creation o Written using G-codes and M-codes to describe the sequence of operations. Can be created manually or using a CAD/CAM system, often done offline.
2. Loading the Program
   o The part program is loaded into the machine’s computer (controller). o It can be edited or simulated using the controller’s input device.
3. Execution
   o The controller processes the program and sends signals to the machine
   components. o The machine performs operations as per the programmed instructions.
4. Advantages of CNC:
5.  High accuracy and repeatability
    Requires less operator skill
6.  Greater flexibility
    Reduced inspection needs
    Simplifies complex machining tasks
   Disadvantages of CNC:
7.  High initial investment cost
8.  Higher maintenance requirements
    Not cost-effective for low-volume product