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The shape : the top view

Create a new document (we will import the profile later). Now we have to define the main shape of the foil. I like elliptical shapes, but others will be fine. Create a new layer to store the shape outline. Try to put the middle of the shape at the (0,0,0) point, so it will be easy to create half the foil by mirror. It's easy to compute the area and the span of the kite, and therefore the Aspect Ration (AR). The formula is :

AR = Span × Span / Area

With Rhino, to compute the area, create a surface from the outline (Surface>From planar curves) and get the area (Analyze>Mass Properties>Area). We'll get something like that :

On the above picture, I've drawn the span line, and divided into as many segments (cells) as I want. Take a few minutes now to try to figure out how you'll make the bridle, so you can have the correct number of cells. I draw a vertical line (position of the center profile) and I duplicate this line to get the positions of every profile.

Using a trim function, I truncate the lines to the correct length. Notice that I've done equally sized cells, but it's not mandatory.

Here, I've only kept the ends of each line, to facilitate the placement of the profiles. We are ready to put the profiles. First, import the profile.

After profile import. It's easier if the profile is bigger than the biggest chord.

Using a copy function, put a profile on each position, placing the origin of the chord on the leading edge.

Now, adjust each profile to the correct size. If your CAD tool allows it, lock the shape's layer. For each profile, select all it's elements (cross vents, marks, outline, ...) and scale it (scale 3D). Under Rhino, select the origin of the chord as the scale origin, the end of the profile as the first reference point and the end of the chord as the second reference point. You get :

Notice that I don't have tip profile. It's a design choice, not a tool limitation. I usually make a round tip, but if you don't want a tip profile, but want a straight tip, create a line (on the profile's layer) at tip.

Make a backup of your work NOW !
It's mandatory if you want to create patterns.

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