Creating and editing the defining curves manually

The radii and eccentricity curves can be created manually by digitising points relative to the axes in a buttock view (port or starboard). See Creating Planar Curves for further information about creating curves in PACE.

There are two ways by which the data points defining the radii and eccentricity curves can be precisely positioned.

• Right-clicking on the curve in question and selecting Data point at waterline... , launches a dialog (see Figure 3:90 below) in which to enter the waterline height (that means, z-value) at which to insert the point, and the corresponding radius or eccentricity value. Clicking OK inserts this data point into the curve

  

  Figure 3:90. Inserting a data point into the radii or eccentricity curve at a precise position.

• Existing data points appear in the Data Points grid of the Data Bar, and can be manipulated in the same way as points for any other curves (see Figure 3:91 below). See also Data Bar - Curves Grid.

Figure 3:91. Radii / eccentricity curve data points can be viewed and edited in the Data Points grid of the Data Bar.

The end surface will only be defined where the radius value is greater than zero. Therefore, there will be no surface in regions outside the vertical extents of the radii curve. A gap in the end surface can be created by making the radii curve equal to zero over the appropriate vertical region. Usually this would be done by inserting knuckle or tangent points as shown in example in Figure 3:92 below.

Figure 3:92. Producing a gap in the end surface by making the radius curve zero valued.

Note: It is important that the horizontal value of the radii curve is nowhere greater than the instantaneous radius of curvature of the corresponding point on the profile curve, unless this point is concave with respect to the inside of the hull form. Otherwise, the end surface will crease over on itself.