GINGERBREAD GEODESICS

Enlarge Image Image Gallery This modern, magnificent gingerbread structure could bring fairy-tale magic into any holiday home!

There's something special about those seven days before Christmas. Maybe it's the holiday magic in the air or just having the children home on vacation. At any rate, we always get the urge to undertake some memorable family project during that preYule week. And this past year, it involved constructing a gingerbread house . . . but not your run-of-themill, four-walls-and-a-roof variety. Oh, no! It had to be very, very special . . . a dome-a miniature replica of our dream home-made of cookies, candy, and lots of love!

Building this dream, however, wasn't as easy as we had first imagined. Before we could even whip up a batch of gingerbread, it was necessary to research dome construction, make patterns and models, and prepare a stepby-step building plan.

DOME ARCHITECTURE

I soon found myself with every dome building book our local library had to offer, boggled down in terms such as trapezoidal icositetrahedron, hexakis octahedron, and triakis icosahedion. Angles, strut lengths, and complicated mathematical computations added to the confusion. Fortunately, I soon discovered that domehome basics aren't nearly so mystifying as some books would lead you to believe. Geodesic structures are simply strong, light, convexly curved buildings approximating spheres or half-spheres. (Geodesic is a mathematician's term for the shortest distance between two points on the surface of a sphere.) The dome's surfaces are strong, because-like a set of interlocking arches each supports the others. When the basic units triangles attached in five-part (pentagonal) or six-part (hexagonal) sections are hooked together, the result is a simple, symmetric shape that needs little in the way of additional supports such as beams or columns. And because this type of dome is made of many identical parts (of which the majority are triangular), it's very well suited W for mass construction . . . and for ginger' bread houses.

The version we chose was a modified dome structure-adapted from plans in a li brary book-with hexagonal sections, top spacers, bottom risers and spacers, and rectangular doorway and window pieces (see the illustration). I estimated that the gingerbread version would be about one-tenth the size of the house in the plans, so I developed a pattern by dividing by ten all the measurements given in the book.

Next, I cut pattern pieces from lightweight cardboard (old file folders), and taped them together to make a model. This was an invaluable aid in visualizing the actual angles, shapes, and three-dimensional relationships.