CNC Machining Types and Terms

  • CNC drilling is an automatic machine process utilizing a drill to cut parts.
  • CNC machine shop is a place where materials are shaped by CNC machines.
  • CNC milling, also known as "CNC turning," is possibly the most common kind of CNC machining. CNC milling machines are classified according to the number of axis points that they use. Typically these machines have at least three axes, X and Y for horizontal movements, and Z for verticals; some machines, however, utilize five axis points with extra pivot points.
  • CNC punch machines cut parts on computer numeric control systems.
  • Machine work shapes materials into precise forms.
  • Precision laser machining is the precision cutting of parts with a laser using CNC machines to control the laser to ensure accuracy.
  • Precision machining is the process that uses a computerized machine to ensure exactitude.
  • Prototype machining is often performed by CNC machines to create a part or object which will be a "mock-up" or model of a future final part. Prototypes are used to prove feasibility, but often are not as efficient or well-designed as later production models.

A-Axis - A machine tool members circular axis motion or slide about the x-axis; values along the a-axis are the degrees of rotation about the x-axis.

Absolute System - An NC system that ensures all positional dimensions are in reference to a shared datum point; includes both feedback and input.

Analog - Referring to a system which utilizes electrical voltage ratios or magnitudes to represent physical axis positions.

American Standard Code for Information Exchange (ASCII) - Established by the American Standards Association as a data transmission code in America.

Axis - The relative movements of a work piece or tool in a primary direction, consisting of three linear axes, which are at ninety degree angles from each other; the X,Y for horizontal movement and Z for vertical movement.

Axis Inhibit - A characteristic of a numerically controlled unit that gives operators the ability to withhold command information from machine tool slides.

Axis Inversion
- Also called "mirror image," this machining command procedure is used to create a reverse or mirrored part by reversing the plus and minus values along a given axis; mirror imaging makes a left oriented part using a right handed oriented tool path; circular interpolation also reverses.

Basic Control Language (BCL) - A CNC controller language using the EIA/ANSI 494 software.

Backlash - The relative movement between interacting mechanical parts as a result of looseness.

B-axis - Circular motion of a machine tool along around the y-axis.

Binary Code - Code based on binary numbers expressed as either 1 or 0, denoting true/false or on/off, etc. The primary programming language of CNC machines.

Block - A single line of NC code representing enough information to a CNC machine to execute a single arc or line movement.

Block Delete - A function allowing the control system to ignore any select block of code, at the operators control.

CAD/CAM - Computer Aided Design / Computer Aided Manufacturing; this is the use of computers to assist in both the development and manufacturing phases.

Computer Aided Design (CAD) - Utilizing computers to assist the development phase of design.

Computer Aided Manufacturing (CAM) - Utilizing computers to assist in manufacturing processes by the computerized control of the tooling process.

Clockwise Arc - Coordination between two axes produces an arc and its curvature is clockwise in respect to the part being machined and the Cartesian planes.

Counterclockwise Arc - Coordination between two axes produces an arc that has a curvature that is counterclockwise in respect to the part being machined and the Cartesian planes.

G-Codes - The assembly language for CNC devices. Each machine instruction corresponds to a fundamental movement of the robotic mechanism.

Flash - A thin fin of material which forms at the parting line of the mold.

Lathe - A machine tool for shaping metal or other material. The material is turned about a horizontal axis while it is shaped by a fixed tool.

Linear Interpolation - A control function in which data points are created between given coordinate positions to permit simultaneous movement along one or more axes of motion in a linear path.

Manual Part Programming - The process of creating a manuscript in the machine control language format that defines the series of commands for a CNC machine.

Modal - The retention of information by a CNC computer system until new information is received to replace it.

Offset - A displacement of a tool along an axial direction the same as the difference between the real length and the inputted tool length.

Overshoot - The quantity to which axis motion goes beyond the targeted value.

Parameters - The variables which determine the dimensions of a machined part as well as the operational sequence of the machine tools used to produce the part.

Tooling - The selection of tools needed to produce the desired contours and dimensions of a machined metal part.