Command Modes

The Size command defines four different modes. These modes allow you to enter, calculate, and report different kinds of size calculations:

1. ASME Y14.5

   The Size command in this mode does the following:

   • It records a nominal size, an upper deviation limit, and a lower deviation limit.

   • It calculates the unrelated actual mating envelope. The command also calculates a long list of local sizes.

   • It reports the actual mating envelope. The command also reports the worst of the local sizes.

2. ISO 14405-1, Nominal with Deviation

   The Size command in this mode records a nominal size, an upper deviation limit, and a lower deviation limit.

   • If there is a single specification operator, the operator applies to both limits.

   • If there are two specification operators, each operator only applies to one limit.

   • If a specification operator is a global size, that global size is computed, and the report compares the global size to the applicable limit or limits.

   • If a specification operator is a local size, a long list of those local sizes is computed, and the worst local size is reported for each applicable limit.

3. ISO 14405-1, ISO Code

   The Size command in this mode records a nominal size and an ISO code. This information, together with ISO 286-1, define the limits of size.

   The ISO 286-1 standard defines hundreds of tolerance codes that look somewhat like "E9" and "H7". These tolerance codes are all supported by the size command. Reporting is much like the ISO nominal-with-deviations mode.

4. ISO 14405-1, Range of Sizes

   You should use this mode with the range of sizes modifier defined by ISO 14405-1 (the text SR enclosed in an oval).

   The Size command in this mode does the following:

   • It only records one specification operator.

   • It does not record a nominal size, nor limits on deviations.

   • It records a single tolerance value, because the range of sizes modifier produces specification operators that are similar to form tolerances. For an example, see Figure 17 in the ISO 14405-1 standard. Reporting in this mode is similar to reporting for form tolerances.