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Step 2. Create the 3D curves. To make the three surfaces, you need to create the 3D crest curves. This is done by making a 2 Projection curve, i.e., select the side datum and the long crest curve from the profile body curve set, and project it to the top datum and the inner long crest curve (Fig. 8). This is the same thing as creating two surfaces, one through each curve normal to their respective planes and creating a 3D curve at the intersection of the two surfaces. While it can be done this way, you end up with a pair of curves that have to be layered off.

Figure 8.

The front 3D crest curve is created the same way, this time using the top datum as a reference and the top forward crest curve projected to the front datum and the forward crest curve (Fig. 9).

Figure 9.

The front outside corner 3D crest is created by selecting the side datum and the inner corner crest curve and projecting to the front datum and the forward corner curve (Fig. 10).

Figure 10.

After creating the curves, modify some of the dimensions and make sure everything moves correctly.