Part Modeling > Base Features > Extrude > Basics of the Extrude Feature > About a Surface Trim Created with the Extrude Tool
  
About a Surface Trim Created with the Extrude Tool
You can use the Extrude tool to trim a quilt by projecting a sketched section onto a quilt normal to the sketching plane.
 
* To create a surface trim, you must have a quilt in your model.
A section outline defines the trim boundary in a quilt. A section can be open or closed. Consider the following rules about sections:
A closed section can lie within or intersect the quilt boundaries.
An open section must intersect the quilt boundaries.
Depth Options for Trim Surface
To define the depth of the extruded surface trim, use one of these depth options:
Blind—Extrudes a section from the sketching plane by the specified depth value.
Symmetric—Extrudes a section on each side of the sketching plane by half of the specified depth value.
To Next—Extrudes a section to the next surface. Use this option to terminate a feature at the first surface that it reaches.
 
* You cannot use a datum plane as a terminating surface.
Through All—Extrudes a section to intersect with all surfaces. Use this option to terminate a feature at the last surface it reaches.
To Selected—Extrudes a section to one of the following:
—Extrudes to a selected point, curve, plane, or surface.
—Extrudes to an offset of a selected point, curve, plane, or surface.
—Extrudes to a translation of a selected point, curve, plane, or surface.
 
* The terminating plane must be parallel to the sketching plane.
Selecting the Portion of the Quilt to Keep
When you trim a quilt with a projected section, you can choose which portion of the quilt to keep, or you can keep both portions of the quilt.
 
* If you keep both sides of the quilt, you must select which portion of the trimmed quilt inherits the quilt ID.