About Sweeps
Create a Sweep feature by sweeping a cross-sectional sketch along one or more trajectories. You can control the object’s orientation, rotation, and geometry.
Material can be added or removed as the sketch sweeps along the trajectory. You can add a thickness to the sketch. The geometric representation of the sweep can be solid or surface.
You can merge the end of a solid sweep to a nearby solid surface without leaving a gap. You can close each end of a surface sweep if the sketch forms a closed loop, and the trajectory is open. When you create cut, trim, or thin features, use the arrows in the graphics window to indicate the direction of the tool operation.
Sweep trajectories
The main components of the Sweep tool are the trajectories. The sketched section sits on a frame that is attached to the origin trajectory and moves along its length to create geometry. The origin trajectory, along with the other trajectories and other references such as the planes, axes, edges, or an axis of the coordinate system define the orientation of the sketch along the sweep.
Sweep sketch
The sketch can be constant or variable:
• 
Section Unchanged—The sketch does not change its shape as it is swept along the trajectories. Only orientation of the frame on which the sketch lies changes.
Section Unchanged—The sketch does not change its shape as it is swept along the trajectories. Only orientation of the frame on which the sketch lies changes.• 
Allows section to change—Constrains the sketch entities to other trajectories (pivot plane or existing geometry) or uses relations with the trajpar parameter to make the sketch variable. The references to which the sketch is constrained change the shape of the sketch. Also, defining the dimensioning scheme by relations (with trajpar) makes the sketch variable. The sketch regenerates at points along the trajectory and updates its shape accordingly.
Allows section to change—Constrains the sketch entities to other trajectories (pivot plane or existing geometry) or uses relations with the trajpar parameter to make the sketch variable. The references to which the sketch is constrained change the shape of the sketch. Also, defining the dimensioning scheme by relations (with trajpar) makes the sketch variable. The sketch regenerates at points along the trajectory and updates its shape accordingly.When you create a sweep, the sweep sketch type is automatically set to constant or variable depending on the number of trajectories you select. One single trajectory sets a constant sweep, and multiple trajectories set a variable section sweep. If you add or remove trajectories from the sweep feature, the sweep type adjusts accordingly. However, you can override the default and set the sweep type manually by clicking or .
or .Sweep frame
The frame is essentially a coordinate system that slides along the origin trajectory and carries with itself the section to be swept. Axes of the coordinate system are defined by auxiliary trajectories and other references. The frame determines the orientation of the sketch as it is being moved along the origin trajectory. The frame is oriented by additional constraints and references such as the Normal To Trajectory, Normal To Projection, and the Constant Normal Direction (along an axis, edge, or plane).
Creo places the sketch in a certain orientation in relation to these references, and attaches it to a coordinate system that moves along the origin trajectory and sweeps the sketch.