What is CNC Machine ?
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.
Numerical control (NC) (also computer numerical control (CNC)) is the automated control of machining tools (drills, boring tools, lathes) by means of a computer. An NC machine alters a blank piece of material (metal, plastic, wood, ceramic, or composite) to meet precise specifications by following programmed instructions and without a manual operator.
NC machines combine a motorized maneuverable tool and often a motorized maneuverable platform, which are both controlled by a computer core, according to specific input instructions. Instructions are delivered to an NC machine in the form of graphical computer-aided design (CAD) files, which are transformed into a sequential program of machine control instructions, and then executed.
CNC Machine Parts
This holds the material to be cut or shaped. Material must be held securely otherwise it may ‘fly’ out of the vice when the CNC begins to machine. Normally the vice will be like a clamp that holds the material in the correct position.
The guard protects the person using the CNC. When the CNC is machining the material small pieces can be ‘shoot’ off the material at high speed. This could be dangerous if a piece hit the person operating the machine. The guard completely encloses the the dangerous areas of the CNC.
This holds the material that is to be shaped. The material must be placed in it very carefully so that when the CNC is working the material is not thrown out at high speed.
The motor is enclosed inside the machine. This is the part that rotates the chuck at high speed.
The LATHE BED
The base of the machine. Usually a CNC is bolted down so that it cannot move through the vibration of the machine when it is working.
The CUTTING TOOL
This is usually made from high quality steel and it is the part that actually cuts the material to be shaped.
CNC CONTROL PANEL
A CNC machine is normally controlled by a computer and software. However, most CNC machines have a range of controls for manual use. It is rare for a CNC machine to be used manually as simple operations are best carried out on cheap/basic/manual machines. When a CNC machine is used manually it is been used well below its capability and specification.
The must important control button is usually the reset button. When the CNC machine is turned on, the reset button is pressed by the machine operator. This ‘zeros’ the cutter, moving the cutter to coordinates 0,0,0 on the X,Yand Z axis. In simple terms, the reset button moves the cutter to the corner of the machine, above the work table. If the reset button is not pressed, it is possible that the CNC machine will start cutting the material in the wrong place or even miss cutting the material and plunge into the work table.
The cutter can be controlled manually although this is rarely needed. The ‘X’ and ‘Y’ buttons control the movement of the cutter along the horizontal surfaces. The ‘Z’ buttons control depth and up / down movement.
Most control panels have stop buttons. When pressed these stop the machine very quickly.
SPEED AND FEED
On some CNC machines it is possible to manually vary the speed and feed of the cutter.