(For information on accessing the dialog box that contains this item, see "Editing CAD Elements".)
You can use the Set as Priority check box on the Edit CAD Elements dialog box to define a prioritized set of CAD surfaces for Find Noms (find nominals) processing. These are called "priority surfaces".
Prioritizing surfaces speeds up the calculation of nominal values as it allows PC-DMIS to determine which surfaces to check first. There is no limit to the number of surfaces that you can select. The order that you select the surfaces determines the order of the search.
Whenever you open the Edit CAD Elements dialog box and select the Set as Priority check box, PC-DMIS automatically selects the previously stored set of surfaces.
Setting Priority Surfaces
Select Edit | Graphic Display Window | CAD Elements.
If the Set as priority check-box is not marked, mark it now. PC-DMIS highlights any surfaces that are already prioritized.
Select surfaces in the Graphic Display window to add or remove them to this list.
Click Apply or OK button to update the measurement routine with the changes made to the list of priority surfaces.
Storing a New Set of Priority Surfaces
Open the Edit CAD Elements dialog box (Edit | Graphic Display Window | CAD Elements).
Select the Set as Priority check box. If you've already defined a set of surfaces, PC-DMIS selects them in the Graphic Display window.
With the Set as Priority check box selected, click the Deselect button and then click the Apply button. This essentially tells PC-DMIS to clear any stored surfaces.
Deselect the Set as Priority check box.
Select the new set of surfaces to store.
Select the Set as Priority check box.
Click the Apply button.
Click OK.
Box-Selecting and Priority Surfaces
When you box-select with the Auto Features dialog box open, PC-DMIS selects all CAD surfaces of the feature type inside the box.
To limit which surfaces PC-DMIS selects inside the box, you can specify the priority surfaces. That is, if you've defined priority surfaces using the Edit CAD Elements dialog box, when you box-select from a surface Auto feature, PC-DMIS considers only the priority surfaces for that feature.
PC-DMIS uses priority surfaces for other functionalities, including Find Noms.
For more information on how to box-select to create features, see "Box Selecting to Create Multiple Auto Features" in the "Creating Auto Features" chapter.