About the Extend User Interface
The Extend tab consists of commands, tabs, and shortcut menus. Click > 
Extend to open the Extend tab.
Extend to open the Extend tab.Commands
• Type
◦ 
Along Original Surface—Extends the surface boundary edge chain along the original surface.
Along Original Surface—Extends the surface boundary edge chain along the original surface.◦ 
Up to Plane—Extends the boundary edge chain up to a specified plane in the direction normal to this plane.
Up to Plane—Extends the boundary edge chain up to a specified plane in the direction normal to this plane.• Settings
◦ Along Original Surface
Along Original Surface▪ 
Extend by—Sets a value for the distance to extend for a constant extension. Not available for a variable extension.
Extend by—Sets a value for the distance to extend for a constant extension. Not available for a variable extension.▪ 
—Flips the direction of the extension relative to the boundary edge chain. Not available for variable extensions.
—Flips the direction of the extension relative to the boundary edge chain. Not available for variable extensions.◦ Up to Plane
Up to Plane▪ 
Plane collector—Displays the reference plane for the Extend feature.
Plane collector—Displays the reference plane for the Extend feature.Tabs
• References
◦ Boundary edge collector—Displays the edge chain for a surface extension.
▪ Details—Opens the Chain dialog box.
◦ Reference plane collector—Displays the reference plane for the Extend feature when Up to Plane is selected.
Up to Plane is selected.• Measurements
Available when Along Original Surface is selected. Lets you create a variable extension by adding and adjusting measurement points along the selected edge chain. By default, the system adds only one measurement point, which extends the entire chain by the same distance to create a constant extension.
Along Original Surface is selected. Lets you create a variable extension by adding and adjusting measurement points along the selected edge chain. By default, the system adds only one measurement point, which extends the entire chain by the same distance to create a constant extension.There are two ways to measure the extension:
◦ 
—Measures the extension distance along the extended surface.
—Measures the extension distance along the extended surface.◦ 
—Measures the extension distance in the selected datum plane.
—Measures the extension distance in the selected datum plane.• Options
Available when Along Original Surface is selected.
Along Original Surface is selected.◦ Method—Selects the extension method.
▪ Same—Continues the surface past its original boundaries, keeping the same type of surface.
▪ Tangent—Extends the surface by making it a ruled surface tangent to the original surface.
▪ Approximate—Extends the surface as a boundary blend.
◦ Extension side 1 and Extension side 2
▪ Along—Creates the extension side along the selected side edge. If more than one side edge is available, use the next collector to select one.
▪ Normal To—Creates the extension side normal to the connected boundary edge.
• Properties
◦ Name box—Sets a name for a feature.
◦ 
—Displays detailed component information in a browser.
—Displays detailed component information in a browser.Shortcut Menus
Right-click the graphics window to access shortcut menu commands.
• Boundary Edge—Activates the Boundary edge collector.
• Reference Plane—Activates the Reference plane collector for an Up to Plane extension.
Up to Plane extension.• Measurement Point—Activates the Measurement Point collector under Reference on the Measurements tab for an Along Original Surface extension. If there is more than one measurement point collector, the last active measurement point collector is activated. This menu item is available only when the Measurements tab is open.
Along Original Surface extension. If there is more than one measurement point collector, the last active measurement point collector is activated. This menu item is available only when the Measurements tab is open.• Measurement Edge—Activates the Measurement Edge collector for an Along Original Surface extension. If there is more than one measurement edge collector, the last active measurement edge collector is activated. This menu item is available only when the Measurements tab is open and one or more measurement edge collectors are present.
Along Original Surface extension. If there is more than one measurement edge collector, the last active measurement edge collector is activated. This menu item is available only when the Measurements tab is open and one or more measurement edge collectors are present.• Measurement Plane—Activates the Measurement Plane collector for Along Original Surface extension. This menu item is available only when extension distance is measured in the measurement plane.
Measurement Plane collector for Along Original Surface extension. This menu item is available only when extension distance is measured in the measurement plane.• Side Edge 1—Activates the side edge one collector for Along Original Surface extension. This menu item is available only when more than one side edge exists for extension Side 1.
Along Original Surface extension. This menu item is available only when more than one side edge exists for extension Side 1.• Side Edge 2—Activates the side edge two collector for Along Original Surface extension. This menu item is available only when more than one side edge exists for extension Side 2.
Along Original Surface extension. This menu item is available only when more than one side edge exists for extension Side 2.• Clear—Empties the active collector.
• Flip—Changes the direction of the extension.
Right-click the drag handle to access shortcut menu commands.
• Normal to Edge—Extends the surface normal to the selected edge.
• Along Edge—Extends the surface along the side edge.
• To Vertex Parallel—Extends the surface at the vertex and parallel to the boundary edge.
• To Vertex Tangent—Extends the surface at the vertex and tangent to the next one-sided edge.