scope:

This CID covers computer numeric control (CNC), horizontal-spindle, slant-bed lathes and turning centers intended for turning, boring, drilling, reaming, tapping, and facing of workpieces of cast iron, steel, titanium, aluminum, brass, graphite epoxy, and composite materials, for use in Aircraft Metals Technology Shops across the Air Force. The equipment identified herein shall be manufactured in the United States of America.

CNC milling is an automated machine process used to manufacture engineering parts by selectively and progressively removing material from a workpiece. Material removal (milling) occurs via use of a rotating multi-point cutting tool and computerized controls (i.e., CNC). Parts manufactured via CNC milling are most practical via use of Computer-Aided Design (CAD) and Computer-Aided Manufacturing (CAM) software. CAD enables development and design of a part. CAM programs are used to generate manufacturing tool paths and to automate the manufacturing processes; CAM converts the CAD model into an executable CNC program (.NC) for machine use. This results in CNC manufacturing (machine control), instructing (via "G-code") the machine to execute the job in order to manufacture a physical part.

G-code, per Electronic Industries Alliance (EIA) RS-274, is required as the programming language; it describes geometric paths using a simple command structure of the letter "G" followed by a numeric value.