Simple Planing Hull Form using X-Topology

This tutorial goes through the process of creating a simple planing craft hull.

1. Using a X-Topolology curve, create a centreline. In addition to the ends use two control points for the forefoot.

2. Select the two points representing the forefoot of the bow and apply a blended segment constraint.

3. The centreline will now be straight along the keel and stem with a blended curved in between.

4. Starting at the top of the stem, draw a deck line curve. Four control points, in total, should be enough.

5. Starting from the upper point of the forefoot blend, draw a chine line curve. The curve should have the same number of points as the deck line to maintain the same shape structure.

6. Select the chine line and apply a 'Knuckle Line' ribbon surface tangent.

7. Draw a transom line, from the centre line, through the end of the chine line and ending on the deck line. The 'knuckle line' tangent information applied in the previous step cause the curve to have a sharp corner as it passes through the chine curve.

8. Add a section curve, starting at the low point of the forefoot, passing through the chine line and ending at the deck line.

9. Select the section curve...

...and apply an x-plane location surface.

10. Create the X-Topology surface by selecting all the curves...

...and generating the surface using the option on the Right-Click menu, (Right-Click -> Multiple Selection -> Create XTSurface Group).

11. As the hull has been built up from sketched curves, the shape is not particually good. The deck line can be edited to improve the shape of the top of the hull.

12. The chine line should be updated to improve the shape of the lifting portion of the hull surface.

13. Setting up and displaying contours on the hull surface will highlight any undesirable areas. Curves can be interactively edited, using the shape of contours as a guide to improve the shape of the surface.

14. A reasonable hull shape should be achievable fairly rapidly.

15. Select the surface and change the colour from white.

16. Render the surface to review the quality of the hull.

17. Change can be made to the surface while it is displayed in render form. Further points can be added to the section curve above the chine line to create flare in the bow.

18. Continue fairing the hull by modifying control points or adding more curves until the quality of the shape is satifactory.

Simple Ship Bow Section using X-Topology >>>