Preparing to Create Splines Click Plane (Sketch toolbar). In the FeatureManager design tree, select Right Plane for First Reference. In the PropertyManager, under First Reference, click Coincident , then click . A 3D sketch plane, coincident to the Right plane is added to 3DSketch1. Click Centerline (Sketch toolbar), and use inferencing to sketch a horizontal construction line through the center of the circle. Clear the Centerline (Sketch toolbar) tool. Parent topic3D Sketching with Planes Previous topic Adding Relations Between 3D Sketch Planes Next topic Creating the First Splines