The surfaces are intersected. Two curves-on-surface are created, one on
each surface.
By default, the Intersect tool creates a curve-on-surface on each surface
so each surface can be trimmed.
Both surfaces are now drawn with a dotted outline to indicate that each
has a curve-on-surface.
5 Choose Pick > Object Types > Curve on Surface .
298 | Chapter 6 Modeling a Vacuum Cleaner