NOTE 1 The numerical control (NC) is assumed to have access to complete description of specific tools in a database. The milling_machine_tool_schema defined in this part of ISO 14649 serves as a basic tool schema, including the information required by the CNC to select a tool from the machine tool's tool magazine.

NOTE 2 In ISO 6983, the tool is defined by its identifier (e.g. “T8”). No further information concerning the tool type or geometry is given. This information is part of the tool set-up sheet, which is supplied with the NC program to the machine. The tool set-up sheet gives the relationship between the tool location (e.g. “slot 8 of the tool magazine”) and the type of tool (e.g. “drill 4 mm”).

NOTE 3 It is important to understand that all length measure types used in this part of ISO 14649 are not toleranced length measure types because they are used to describe the tools required for the manufacturing of a workpiece, not the actual dimensions of the tools available at the machine. A real tool will be selected by the tool management based on the actual tool dimensions and the tolerances of features.