Delete individual faces , or all faces of a lump
The operation creates a Delete Face feature in the browser and automatically converts the part to a surface.
If necessary to heal gaps between remaining adjacent faces, click Heal.
If necessary to delete a void , pause the cursor over a void face. Because the void is inside the model, the exterior face is selected first. When the Select Other symbol appears, click the arrow to cycle through selections, then click to select the void.