Whistlepig Farm Sundial

A closeup of the sundial face at 12:22 p.m.

In January of 2010 I was approached by my friend Tom Sherry about designing and fabricating a sundial to be located at his home and farm near Asheville, North Carolina. Tom wanted a sundial that would function well, look good and include a commemrative element of his upcoming wedding in May. Other than these parameters I was given broad latitude in the design process.

This sundial is located at Tom’s home and farm, Whistlepig Farm in Candler, North Carolina, approxamately 20 minutes west of Asheville, NC at 35.4831N ,-82.7452W. The wall that the dial was to be mounted to was measured at least three times over an hour long period on several different days and found to face 8.6 degrees east of south.

The dial elements were determined using Fer J. de Vries’ program zw2000. Declination lines were drawn for the 21st of each month. An additional declination line was drawn for the 29th of May as a commemorative marker of the wedding day. Hour lines are drawn and indicated for Eastern Standard Time with daylight savings time and londitudinal corrections. Lastly, a line was drawn indicating solar noon.
Importing the dxf file into Adobes Illustrator program, I was assisted by Alice io Oglesby in the coloring and typography of the dial face. The intent was to imply a mountain sunset scene with rows of crops in the foreground that would incorporate the functional elements of the dial face.

The final sundial is 45 x 21 inches in size and was printed by a local sign shop. The base material of the dial is .080 aluminum signboard that has a baked enamel finish with a printed vinyl applied to the sign board. This material has a warranty of 3 years before fading may occur, but in practice has a life much greater than that depending on environmental variables. The gnomon is a 1.575 inch long .250 inch diameter steel shaft with a conical end and rounded tip of .030 inch radius that is mounted horizontally and bolted to the dial face from behind using a #8-32 machine screw. The dial is mounted to Tom’s house on a pressure treated lumber framework that sets the dial face approximately 14 inches away from the wall surface. This allows for unobstructed illumination of the dial face from the soffit overhang above the dial during the summer solstice.

One final note about this dial regards Tom’s facination with prime numbers. The date and time of the wedding were chosen to all be prime numbers, May (5), 29th, (29) 4:33 pm (433). Additionally the sum of these three numbers is 467, which itself is a prime number.

The Whistlepig Farm Sundial on the side of the house.