Started a new sundial this week: a double polar dial with circular base. Hadn't seen one like it before, but finally find one (1) that was done as a collaboration between sculptor Kate Pond and the well regarded dialer Bill Gottesman, both from Vermont. Oh, well.
This has been one of the most challenging sundials that I've build. Most designs are a bit forgiving considering the slightly lower accuracy (5 minutes) that I impose on my dials. In this case, there doesn't seem to be much room for error. The equations of time are pretty straightforward, but transferring those to a small prototype has been been difficult for some reason. Finally resorted to a full scale drawing and then things fell into place. Some crazy geometry.
The prototype is only a little over 45" in circumference while the final dial will be about 106". I am using my 6 ton flypress to form the hoop and will have to build some new tooling when I go to the larger dial.
So far the tests on the calculated equations of time seem to indicate that I have the calculations 'dialed' in (see what I did there- sorry).
I will likely turn the prototype into a small garden sundial for a table or maybe mount on a rock to sit on the ground. Definitely going to try an 'instant rust' patina.
the Mad tinker
Just an archive of projects as they progress. Nothing really to see here. Move along ...