Creating the Parallel Middle Body

7. Curves forming the extents of the parallel middle body of the hull form can be created by translating and copying the midship section curve. Select the curve and from the main tool bar, press the button, to bring up the translation dialog. Create a copy of the midship section curve 1.0m forward by putting 1.0 in the X (length) box and select the "create a copy" check box. Press OK.

The new curve appears forward of the original.

6. Repeat the process to create the aft extent of the parallel middle body. Select the midship section curve and press the button. Translate the curve by -1.0m this time. Select the "create a copy" check box and press OK.

There should now be three curves.

8. Before proceeding, rename the centre curve as "Midship", forward curve as "FwdParallel" and aft curve as "AftParallel". Curves can be renamed by double clicking on the name or by changing the text in the attributes panel.

9. The shape of the curves defining the end of the parallel middle body need to be linked to the shape of the midship section curve. Select the "FwdParallel" Curve...

...and remove all of the existing constraints by pressing the button.

10. In the constraints section of the attributes panel, add an Offset constraint but pressing the button.

11. Select "Offset <no curve>" text in the constraints list to display the Offset Curve Constraint details.

12. In the Offset Curve Constraint Panel select to link to the Midship Curve...

and select the 'X-Axis' radiobutton to create an offset relationship in the X-axis direction.

12. Repeat the procedure on the 'AftParallel' curve by removed the existing constaints and apply an Offset constraint linked to the shape of the midship section curve.

13. Select the 'FwdParallel' curve and press F2 to edit the control points. Drag the control points forward on the flat of side as the image below shows to form the shape of the transition from the bow of the vessel into the parallel middle body. The control points on the flat of bottom do not need to be moved. The Offset constraint only allows the points to be moved in the offset direction. This will be indicated by the mouse cursor icon and the information displayed by the enhanced 3D features.

14. The view can be changed to view in (X/Z) Buttocks and the curvature displayed.

15. Use the curvature display to move the control points and form a reasonable fair curve shaoe.

16. Finish editing the 'FwdParallel' curve, select the 'AftParallel' curve and press F2. Drag the control points on the flat of side aft as in the image below.

17. Drag the control points on the flat of bottom of the 'AftParallel' curve aft aswell.

18. Use the curvature display to achieve a fair curve shape on the flat of side...

...and on the flat of bottom.

19. Create the Bow curve by copying the shape midship section curve. Select the midship section curve and press the button to bring up the translate dialog.

Creating the Bow Shape >>>