The To Faces is an advanced option which allows you to extend the Extrude feature up to a boundary formed by one or more faces. Select the face or faces to which you want to extend the Extrude feature. This is easiest when you have only one profile in the base sketch. If you have multiple profiles in your Base Object, you have to make sure that each profile has at least one face intersecting its extent. Otherwise, an extent error will result.

The extent calculation is the same for all material types. Although the preview will show the direction in which the profile gets extruded, the actual extent will not be calculated until the feature is generated.

To Faces option is quite different from To Next. You can say that To Next does not mean "to the next face," but rather "through the next chunk of the body (Solid or Surface)."

Another noteworthy aspect of the To Faces option is that it can also be used with respect to faces of frozen bodies.

Other Extent Types:

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