Create a Fill feature from the Tools Menu.
Click on the Extraction Type property and select the By Cavity option.
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The faces are then selected for the area that is to be filled:
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Note: The option may only be used in conjunction with Solid bodies. A warning message is displayed if you select faces belonging to Surface bodies.
Finally, the feature is generated and the frozen body that fills the selected depressions is created:
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When Filling a cavity, all faces in the cavity must be selected to complete the Fill operation. As shown here, to Fill a cylindrical cavity, both the base face and the circular face must be selected, otherwise the operation will fail.
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In the case of a rectangular cavity, five faces must be selected: the base face, and each of the four side faces as shown here.
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Fill Using By Cavity Method Limitations
Usage with faces — The method has certain limitations:
You cannot pick faces of Surface bodies.
All faces picked should belong to the same body.