Standard enables data flow between CNC, CAD/CAM

Developed 40 years ago, the ISO 6983/RS274D language for computerized numerical control (CNC) programs was designed when paper tape was used to move data between computers. Previously, the logic necessary to process a simple command was barely affordable for a CNC machine. Until now, even though the average microprocessor can easily process 3D data, CNC programming has historical...

Developed 40 years ago, the ISO 6983/RS274D language for computerized numerical control (CNC) programs was designed when paper tape was used to move data between computers. Previously, the logic necessary to process a simple command was barely affordable for a CNC machine. Until now, even though the average microprocessor can easily process 3D data, CNC programming has historically remained the only function in the design-to-manufacturing process that didn’t use full-fidelity 3D information.

To remedy this situation, AP-238, the official ISO STEP (STandard for the Exchange of Product model data) number for the STEP-NC standard, was recently introduced. In AP-238, the information required to control a machine is linked to the information created by CAD and CAM systems to create an independent, fully documented CNC control file. This will make developing a CNC part program more efficient because the machining instructions can be defined more concisely.

AP-238’s draft international standard is now available on the TC184-SC4 documents Web site as wg3n1534, and will soon be circulated by the various national standards organizations. For those without access to the SC4 site, it can be viewed at ftp://ftp.steptools.com/private/ap238/ap238_dis_package.zip .