Guide Curves & Intersections

6. Create offset-on-surface reference curves

With the curve hidden, use Offset on Surface to generate 0.7 offsets from the ring edges. Select each edge carefully so the offset points toward the top of the solid — click Flip whenever the direction is outward, and repeat the command on every relevant edge with a left click.

7. Blend the lateral offsets and align control points

Connect the two lateral offsets with Blend, flipping Point 1 and Point 2 in the settings window. Working in the Right view (Wireframe if needed), place both points about two grid units above the axis, fine-tune the curvature with the lower control points, and make the curve symmetrical before accepting.

8. Project the curve onto the ring and verify intersections

Move the curve into position along the X-axis, then use Project from the Right view to land it on the solid. Delete the inner curves you no longer need and run Intersect on the remaining guides to check that every curve crosses cleanly.

9. Fix missing intersections and create the base form

If an intersection is missing, select the offending curve’s last control point and, with O-Snap enabled, drop it onto the target curve. Then use Push and Pull to move each side inward by 0.4 and upward by 0.2 mm, and complete the boolean between the ring and the new solid.