Lofting - How to Loft a Fairing  (or boat hull...)
Lofting - How to Loft a Fairing
Lofting is a time honored tradition amongst boat builders. It refers to the tradition of building full scale templates for the boat's hull in the loft of a boat building building(?), then dropping lines down through the loft to the building area that periodically delineate the curve. We fairing builders don't need quite as large a facility, but we still can use some lofting techniques. 

Generally when a fairing is designed, first a person is modeled to determine minimum foot box, knee clearances, shoulder widths, etc. A fairing style is chosen. (short, long, droop nose, head in, head out, how pointy, how rounded, etc.) From this planning and measuring we can determine minimum measurements at various points along the fairing. How do we fill in the points while being sure that the fairing is "fair" to the air? That's where the lofting comes in. Full or fractional scale side and top views of the fairing are created on a plywood sheet, then a thin flexible guide attached to those points and bent so that it matches the desired contour. Fiberglass rod works well for this task. The rod is held in place with nails. Since the rod doesn't want to make any sharp bents, it smoothes out any transitions in the roughed in fairing design. Measurements can then be taken from this shape to allow creation of the actual fairing. Alternatively, numerous CAD programs have been created to allow this step to be performed in Cyberspace. Unless you are a CAD guru, it's probably easier and more productive to do it by hand.

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