Sundial, part deux

So, a sundial is pretty much useless, unless it is in the sun.  I decided, since this was a scientific sundial, indeed a precision instrument, that it needed a precision base.

With left over materials from our last solar job, I fashioned a base using 8 inch sonotube, 3 inch PVC conduit and an 80 pound bag of ready mix.

Scientific Sundial, mounted

Scientific Sundial, mounted

I knew were a large rock, by large I mean car sized, was in my yard,  I found it the first year while digging trenches for drain pipes for the gutters.  I dug down with a post hole digger and placed about 18 inches of sonotube on the rock.  I also drilled into the rock a little bit with a masonry bit and put a 1/2 inch rebar into the rock, pinning the sonotube footing in place.

Then I filled the sonotube and the 3 inch PVC with ready mix concrete.

I waited two days.

Scientific Sundial, about 5 pm

Scientific Sundial, about 5 pm

Using the Solar and Moon calculator App for my android phone, I determined that solar noon was 12:57:58 pm today.  I don’t thing that two seconds will make that much difference, so at exactly 12:58 pm, I aligned the 12:00 noon analemma with the shadow made by the Gnomon.   This sundial is now aligned to true north/south.

The motto means “Life resembles a shadow

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2 comments to Sundial, part deux

  • Richard

    It has been a while. I don’t check everyday, but I do check pretty often to see if you have gotten back to blogging.

    We miss you, man.

    I hope that things are going well.

    I just bought a wood-burning stove and need advice on installing it…? :)

  • Interesting, I didn’t think people still used sundials. I think in many ways taking steps back and going to the basics is actually steps forward. I just found this blog, and I’m glad I did. Good stuff…thanks!

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