Method of Construction

Constructed by: Allison Crawford '98 and Lei Liu '98

Our sundial consists of an engraved, concave hemisphere carved into poured concrete, at the center of which is a vertical pin to cast the shadow. To build this sundial we needed to first make a mold into which to pour the concrete, then engrave the hour lines into the dried stone and insert the wooden pin. To build the mold, we planed about eight million pieces of wood, glued these into a large, eight-inch by sixteen-inch block, then shaped this into a hemisphere on a lathe. We attached a small peg to the inner bottom of this mold so there would be a hole for the pin. Next we built a plywood box, put the mold flat-side down in the center of it, and poured the concrete. When it dried, we removed the concrete from the box and the mold from the center and engraved the twelve equally-spaced chords for the hour lines. Finally, we cut an eight-inch length of wooden dowel, sanded it, and placed it into the center hole.

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