> I have often schemed of easy ways to build an exact replica of
> a kayak, or any boat for that matter. One method I think would work
> would be to lay the kayak on its side, tape wax paper at one foot
> intervals along the sides and laying up some fiberglass making sure
> that the glass extends far enough to create a half shape of a form.
> It would be fairly easy to do. The hardened shapes of glass could
> then be transfered to paper, and the mirror image traced. Of course
> you would have to obtain permission of the boat owner. Now is this
> a copyright infringement? What if the boat owner give permission?
>

What you are proposing is making molds of different areas of the hull and then transferring those to paper. In commercial practice people build a canoe they like from pine or cedar, try it out, and if it is good, they wax it and spray it with chopped glass fibers and resin. This then produces a full hull mold, which might be one piece, or several pieces. To replicate the hull, they just use the same equipment, and spray fiberglass into their mold. Or, they can lay layers of fabric into the mold. The boats are a bit on the heavy side, but there are a lot out there that are made this way.

The boat owner may own the boat, but he does not own the design. To give an analogy. If I bought a house designed by the famous architect Frank Lloyd Wright, I owuld own the home, but it would STILL be a house that was designed by Wright. Because of that design, the house would have a higher value on resale. Knowing that, I am likely to pay more when I purchase the thing. The designer may be dead, but the value of his (or her) work can still be assigned a certain monetary amount by a skilled appraiser. (Do you want to drive a car designed by a nameless design group at GM, or one designed by Mr. Porsche, or Mr. Ferrari?

In his book on strip built canoes Gil Gilpatrick shows how to take the lines off of one canoe for building another one like it. The basic process is to take measurements at the intervals where you will be placing forms ( 12 or 18 inches apart.) At these spots you set up a jig that helps you to measure the amount that the hull varies from the outside edge, for a variety of distances above the keel, or below the gunwale. ( your choice) In effect you get a series of points that can be plotted on a piece of graph paper to give you a cross section at each of the form positions.

Is it ethical? Good question. Gilpatrick was trying to reproduce the handling characteristics of old White brand canoes, which have not been made for decades. There is no one from the White company still around to either get the original plans from, or pay royalties to. Researchers do the same kind of thing for museums, and that seems to be permitted, and even endorsed.

If you want to do something similar to what you have proposed here, I suggest you use plaster of Paris instead of fiberglass. It is much cheaper, and sets in 15 to 30 minutes. Saran wrap will work better than wax paper, too.

You can also use a piece of cardboard, cut to approximate the hull and then scribe a mark on that which is a better fit. Trim the cardboard and try it. If it fits, you have a full size template to trace your forms from. Or you can buy the designs.

Paul Jacobson