Use the Info>Tolerance Report command if you experience problems meshing an assembly model in either native mode or FEM mode. This command displays a report that lists the tolerance values for all assembly components whose model tolerance contributes to the global tolerance for the assembly. If the assembly contains entities such as quilts or beams, the report includes the tolerance value for the assembly itself. The report includes all those components that have geometry, and is arranged in descending order with components that have the highest tolerance values listed first. To better understand how to use the values in this report, you need background information on model accuracy, both relative and absolute.

Tolerance, as reported by Mechanica, is calculated in a manner similar to absolute accuracy. However, the calculated values are somewhat different. You use the Mechanica Info>Tolerance Report command to compare the tolerance—and, in effect, the accuracy—of assembly components if your assembly mesh fails. For Mechanica to mesh the assembly successfully, these values must be very close to each other.

When reviewing a tolerance report, look for significant differences in the tolerance values of components, the assembly as compared to the components, and so forth. Although it can vary depending on the assembly, a significant difference is generally considered to be a difference in the decimal order of magnitude. For example, the difference in two tolerance values of 0.274 and 0.513 would not typically be significant, but the difference between 2.874 and 0.513 probably would be.

If you notice significant differences in the tolerance values reported by Mechanica, return to Pro/ENGINEER and use the Edit>Setup>Accuracy command to decrease the relative or absolute accuracy value for the component whose tolerance value is too high. If you want to change the accuracy value for the top-level assembly, work in assembly mode. If you want to change the accuracy value for one component, work in part mode. When working with the Accuracy command, be aware that a decrease in the accuracy value actually represents an increase in the accuracy, or precision, of the geometry. After you lower the accuracy value, the tolerance value of the component will decrease as well. For more information on accuracy, see the Part Modeling area of the Pro/ENGINEER Help Center.

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