CNC machining frequently asked questions

CNC machining frequently asked questions

We are asked many questions about CNC machining during the week, many from those commenting on our articles. That’s why we have decided to start a series on the most frequently asked question we receive.

This month we start with CNC machining frequently asked questions. If you have any question you would like answering then please comment on this post and we’ll update this section as soon possible.

Keep checking back to see the latest answers.

What is CNC?

Computer numerical control (CNC) is the automation of machine tools by means of computers executing pre-programmed sequences of machine control commands. This is in contrast to machines that are manually controlled by hand wheels or levers, or mechanically automated by cams alone.

In modern CNC systems, the design of a mechanical part and its manufacturing program is highly automated. The part’s mechanical dimensions are defined using computer-aided design (CAD) software and then translated into manufacturing directives by computer-aided manufacturing (CAM) software. The resulting directives are transformed (by “post processor” software) into the specific commands necessary for a particular machine to produce the component and then are loaded into the CNC machine.

What is CNC Machining?

CNC machining is a manufacturing process in which pre-programmed computer software dictates the movement of factory tools and machinery. The process can be used to control a range of complex machinery, from grinders and lathes to mills and routers. With CNC machining, three-dimensional cutting tasks can be accomplished in a single set of prompts.

When a CNC system is activated, the desired cuts are programmed into the software and dictated to corresponding tools and machinery, which carry out the dimensional tasks as specified, much like a robot.

What is the difference between NC and CNC?

NC stands for Numerical Control whereas CNC stands for Computer Numerical Control. In NC Machine the programs are fed into the punch cards. But in the CNC machine, the programs are fed directly into the computer with the help of a small keyboard similar to our traditional keyboard.

What is the difference between CNC and DNC?

DNC (Direct Numerical control/ distributed numerical control) denotes the networking of CNC machines. DNC system uses a large mainframe computer to control a number of NC machines. The program is done externally then sent to individual machines.

What do CNC machinists do?

CNC machinists work with computer numeric controlled ( CNC ) heavy machinery from setup to operation to produce parts and tools from metal, plastic or other materials. Computer numeric controlled equipment is precision machinery that cuts, grinds, or drills into the material.

How many types of CNC machines are there?

There are basically five different types of CNC machines:

  • Plasma Cutting Machine.
  • Laser Cutting Machine.
  • Milling Machine.
  • Router Machine
  • CNC Lathe Machine.

Which materials are used in CNC Machining?

Almost any material can be used in a CNC machine. It really depends on the application. Common materials include metals such as aluminum, brass, copper, steel, and titanium, as well as wood, foam, fiberglass, and plastics such as polypropylene, ABS, POM, PC, Nylon, etc.

What are the 5 axis on a CNC machine?

The term “5-axis” refers to the number of directions in which the cutting tool can move. On a 5-axis machining center, the cutting tool moves across the X, Y and Z linear axes as well as rotates on the A and B axes to approach the workpiece from any direction.

Why is CNC important?

One reason for using CNC machining for production is efficiency. Since computers are used to control machines, it means that all major operations of production can be automated to increase speed and quality of manufacturing. … Another reason CNC machining is beneficial for manufacturing is its accuracy.

What is the difference between CNC milling and CNC lathe?

A lathe turns the material you’re machining and the tools are held stationary in the turret. *Lathes are used mainly for round parts. Milling machines hold the material stationary and the tools do the movement. Milling machines are used for any shape part.

Who is the father of CNC machining?

John T. Parsons. Born January 7, 1913, Detroit, Mich.; the father of numerical control. Parsons discovered how to calculate airfoil coordinates on an IBM 602A multiplier. He then fed these data points into a Swiss jig borer. To date, this was considered the first true numerical control machine as it manufactured goods – helicopter blade templates, in this case – by feeding punched cards into a system, and the system then read and produced the parts based on preprogrammed information.

What language do CNC machines use?

The industry has standardized on G-Code as its basic set of CNC machine codes. G-Code is the most popular programming language used for programming CNC machinery.

What is the difference between CNC and VMC?

CNC is a type of motion control system. It basically means that instead of using cams or templates to cut a part, it is controlled by a computer.

A VMC is a type of CNC machine, typically enclosed and most often used for cutting metal.

What is the difference between CNC and PLC?

There are major differences between PLC (Programmable Logic Controller)  and CNC(Computer Numerical Control) is in the execution of the program. PLC is sequential but CNC is conditional. CNC is a type of application used to control a multi-axis machine tool for example milling machine or lathe.

What is the M code in CNC machines?

M-code (for ‘miscellaneous function’) is an auxiliary command; descriptions vary. Many M-codes call for machine functions like ‘open workstation door,’ which is why some say “M” stands for “machine”, though it was not intended to.

What is a Part Program?

The part program is a sequence of instructions, which describe the work, which has to be done on a part, in the form required by a computer under the control of computer numerical control (CNC) software. It is the task of preparing a program sheet from a drawing sheet. All data is fed into the CNC system using a standardized format. Programming is where all the machining data are compiled and where the data are translated into a language which can be understood by the control system of the machine tool.

The machining data is as follows :

  • Machining sequence classification of process, tool start-up point, cutting depth, tool path, etc.
  • Cutting conditions, spindle speed, feed rate, coolant, etc.
  • Selection of cutting tools.

We hope you enjoyed the first part in a series of CNC machining frequently asked questions, check back for more answers.

Leave a Reply

Close Menu