After many, many trials, I now have a functioning working model of a sky-boat. It has taken longer than I hoped; the details in my grimoire are far sketchier than I had realized. All of the needed techniques are described adequately, but fitting them all together in one device is tricky.
But I have done it!
My model is far from lovely, with none of the attractive lines of the sky-yachts I saw at home in Yorke. It is a plain wooden box in appearance, about a foot long, with four-inch dowels stick up from the four corners