Makes surfaces larger in one or more directions by specifying a distance or a termination plane.
Surface panel
Extend
Distance extends edges at a specified distance. Enter a value or drag the direction arrow to extend the surface dynamically. Default method.
To select an ending face (of a solid or surface body) or work plane on which to terminate the extension.
Optionally, once the termination face is selected, clear the checkbox to terminate to the entire body rather than just the selected face.
Extend creates extended edges along the curve direction of edges adjacent to the selected edges.
Stretch creates extended edges in a straight line from the edges adjacent to the selected edges.