Delete cannot convert a solid into a quilted surface. If a face on a solid is deleted, adjacent faces are extended or modified to heal the model. An error displays if you select a face that cannot be replaced.
The delete command modifies the solid to heal the opening left by the deleted the face. The change depends on model geometry and the selected faces. This table has several examples of delete face operations.
The selected face is tangent to the radial face. The radial face is extended to the planar face.
All faces in the pocket are deleted. The top and end faces are extended.
The model is cut, and the side faces of the pocket are extended
The model is cut, and the bottom face of the pocket is extended.
None of the adjacent can be extended to heal the model, so an error displays.