Frequently Asked Questions
How does the Leap Year cycle affect the readings?
There is no effect on the solar time readings due to the extra quarter-day each year. The solar calendar (shadow length) will lag by a small amount until the next leap day, then will jump slightly ahead of the civil calendar. During April and August with the largest daily length changes the shadow changes by almost an inch each day. The leap day error means the mark will be about a quarter to a half inch behind the average, then jump to a half inch ahead after leap day. I made this sundial about halfway between leap days, so these errors should be small and symmetric.
How precise is the Sundial?
Bigger is better, to a point. In the Summer it is easy to read this dial to within ± one minute of clock time. In Winter, with it's smaller scale it is possible to get within 2 or 3 minutes. The calendar is quite accurate near the marks on the 21st of each month. You have to interpolate between them but with practice can get within a few days of the civil calendar.
As the size of the dial increases, the Summer marks becomes increasingly fuzzy and hard to read. The size of this dial is about the maximum for a half-inch diameter hole.
How long did it take to make?
Disregarding the years of thought and practice dials I've made, I probably have a couple hundred hours of hand labor in this actual sundial. Planning, sketching and trying out ideas that didn't make it to the final design might be a third of that.
Actually marking the data takes seven workdays over a minimum of 6 months, if you start on a Solstice. My work with the data and the art probably covered 10 months, and I'm still doing little additions and tweaks.
What kind of paint did you use?
There is a white primer (Bullseye 1-2-3) under the entire dial. On top are a variety of Latex and Enamel outdoor paints. The bold colors are straight out of the cans; many other shades were mixed by hand as required.
Isn't stucco a problem?
More of a pain than a problem. The rough surface made it harder to do fine details. It is a well-cured wall with no cracks so I'm optimistic it will outlast me.
What happens if the Earth stops spinning?
We'll all just fall on our butts. BAM! Just like that.
Why did you use Daylight Savings Time?
DST is in effect for over 8 months out of 12, so is correct for most of the year. It is used for the larger portion of the sundial below the Equinox line, and some of the region above it. I do have smaller, Standard time hours along the top edge, where they are easily visible during the short winter days.
Is it done yet?
Nope. Call it version 1.0. I'll continue adding details and memorials as appropriate. Also, all the brown areas around the bottom are all a blank canvas to me - I have more ideas than time to do them, but over time those areas will fill in too. Stay tuned ...
Where can I see it in person?
At the Latitude & Longitude listed above. If you are interested enough you'll figure it out.