Masts, spars, daggerboards, flat rectangles | Q: Can you make the surface by sliding one curve along another? If yes: The simplest surface you can use is a Translation Surface. In this surface the moving curve stays parallel to its initial position. |
Keel bulb is foil revolved around axis | Q: Can you make the surface by rotating one curve around a centerline or axis? If yes: You can use a Revolution Surface. |
Aluminum, steel, or plywood construction | Q: Do you want to be able to build your surface out of a flat plate and to fabricate it by bending alone? That is, is your surface required to be developable? If yes: Use a Developable Surface. |
Floor of deck-house taken from deck | Q: Is the surface a piece of a larger surface? If yes: Use a SubSurface or Trimmed Surface. |
Wings, keels, rudders | Q: Are you making an airfoil or a hydrofoil? If your surface will be attached to another surface, use one of the other lofted surfaces with Foil Curves for master curves. |
Sides of deck-house, surfaces of trapezoidal keel | Q: Do you need a simple, somewhat “flat” surface to span the distance between two curves smoothly? If yes: A Ruled Surface probably will meet your needs. If you want to expand it into a flat plate you can use a Developable Surface instead. |
Sails, round-bottomed hulls | Q: Do you think of the surface as being the area inside three or four boundary curves? If yes: Use a Tangent Boundary Surface. |
Decks, chine hulls | Q: Do you want the surface to be freeform, but fixed to two edge curves (the sheer line and chine for example)? If yes: There are two choices: you can use a Ruled Surface, or a B-spline Lofted Surface. |
Hulls, rounded bows, general surfaces | We often use a C-spline Lofted Surface running through transverse B-spline Curves for boat hulls. This is a good combination between the flexibility of B-spline curves for the transverse direction and the stiffness of cubic splines longitudinally. |
Lofted surfaces from measured points | Q: Do you need a surface to pass through a net of control points exactly? If yes: Try a C-spline Lofted Surface defined by C-spline Curve master curves. |