SUNDIAL

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We cast our sundial's face from concrete, first indenting the Roman numerals and the hour lines in the bottom of the 9"-diameter cakepan ... by means of a 1/4"-blade screwdriver and a rubber mal let. In order to have the numerals correctly oriented, the paper must be laid face down in the pan so that the markings will appear backwards when they are transferred to the metal. The inscriptions will then be reversed on the casting, and the face will be "right side to". (If you use the cakepan, screwdriver, and mallet technique, be sure that you back up the pan with end-grain wood and don't pound too hard ... or you'll pierce the container's metal bottom.)

Since the style must be attached to the dial face, you'll need to make allowances for it in the casting. We simply poked two 6-penny nails through the bottom of the pan on the (corrected) noon line, slipped the rubber insulation from some No. 12 wire over the nails, and cast the concrete around them. You should also—before you pour-prepare the mount for the dial itself . . . by hanging a 20-penny nail, from a wire, exactly in the center of the pan and not quite touching its bottom. (The two smaller nails will leave holes in the finished casting, and the bigger one will remain fixed in the concrete.)

To get the smoothest surface possible, we combined two parts cement and one part sand, oiled the inside of the pan, and poured the mixture directly in. We then kept the assembly covered with wet rags for two days to insure very slow curing.

THE STYLE

Your latitude will determine the angle of the style, as indicated in Fig. 3. Although the exact shape-beyond the angle—isn't critical, we've provided you with a basic profile to follow. Our style was made from 18-gauge steel, but any material of similar integrity should be acceptable.

To mount the shadow-caster, you'll need to solder two 6-penny nails-with their heads cut off-to the base of the style. Since the spikes must slip into the holes in the concrete face, and the apex of the latitude angle must be at the dial's focus, be sure to space the nails in accord with the prepared apertures.

THE POST

A number of methods could be used when mounting the dial, but we elected to continue working with concrete. The post's forms were made from 1 X 6 and 1 X 4, with screen door molding tacked inside to provide relief. A 40" length of 5/16" steel fuel line was set down the middle of the form, and a piece of lath with a hole served to hold the tube in place while the concrete was poured. The same two-to-one mixture of cement and sand was used to form a 39"-long post.

PAINT AND ASSEMBLE

As you can see in the photo, we painted both the dial and the post white . .. and then coated the raised Roman numerals, the hour lines, and the style with black paint to provide contrast.

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