Flatten a basic curve onto a plane

Flatten a curve so all its points lie on the same plane. You can flatten the curve onto its average plane, an axis, or an existing reference plane.

You can also link a blend curve to a plane so the blend curve always lies in the plane.

Set up the Curve planarize tool

Choose Curve Edit > Curve Planarize ❒.
- To flatten curves onto their average planes, set Default Projection Plane to Best.
- To flatten curves onto an axis plane, set Default Projection Plane to Axis and then choose the plane.
- To flatten curves onto an existing reference plane, set Default Projection Plane to User Defined Plane.

The User Defined Plane option requires a reference plane object.

Flatten a basic curve onto a plane

Choose Curve Edit > Curve Planarize.
Click the curves you want to flatten.
Click Go.
If you set the Default Projection Plane option to User Defined Plane, click the reference plane you want to flatten the curves onto.