Page 13 Modeling a Sailboat: Rails

The red line in figure below indicates the surface edges of the hull. The steps on this page will show how to create an elliptical rail following this outline.


DupEdge (Curve/From Objects/Duplicate Edge) the top of the hull sides. There is already a curve at the top of the transom, so select and Join the three curves.

Maximize the perspective view.

The two rail curves need to extend far enough to be trimmed back using the bow stem as the cutting object. Use the Extend (Curve/Extend/Extend Curve) command on the rail curve at the bow. At the 'select boundary edges' prompt, hit Enter. At the 'Select object to extend' prompt, select the rail curve and pull a line out off the end of the rail curve.

Put an Ellipse (Curve/Ellipse) near the end of the rail, use the 'AroundCurve' option (A) and hit Enter. Drag the width, or numerically specify the width by typing 4, and then enter 2.5 as the height of the rail.


Select the edge curves, and the curve that is at the top of the transom, and hit Join.

Hit Sweep1 (Surface/Sweep 1 Rail) and select the rail as the path and the ellipse as the cross section curve. Use the 'Roadlike-top,' and 'Refit within .01' options. Notice that the rails extend beyond the top edges of the hull.

Select the two long rails and hit RebuildSrf. Give the rebuilt surface 10 U point and 4 V points.

Select the shorter transom rail and RebuildSrf it with 3 U and 4 V.