Wednesday, August 12, 2015

On the Construction of a Copper Armillary Sphere

Apart from making jewelry for Lithic Design, I have found over the past couple years that I really love making art objects.  Astronomical and nautical instruments have always fascinated me, so I figured an armillary sphere might be the perfect Summer project. 

Armillary spheres are representations of the celestial circles around the Earth.  For instance, these spheres usually have rings like an equatorial colura (measured in degrees with rotation around the North and South axes), an equatorial (measured in degrees with rotation around the East and West axes), and an ecliptic (a western zodiac symbol ring with a 23.4 -degree offset to match the earth's tilt).  

If that all sounds like gibberish to you, you're not alone.  It took a lot of research to figure out what these things symbolized and how they moved.  In the end I still don't really have a firm grasp on most of it.  After hours of researching and sketching, I decided that art value was more important than scientific, mechanical, and historical accuracy for this piece.  I would love to continue learning about these instruments and make a functioning sphere one day, but for now I'm quite happy with how this endeavor turned out.

Here's a look into how my armillary was constructed:

Sketches of the Rings and Sphere Setting

A much fancier stand than I actually created!  Maybe I'll swap it out in the future. 
Hand drawn details for the etching process
holes drilled, all resist applied before etching in ferric chloride
Looking back at this, I really could have just used the thermos body that came with the top...It sure does keep out particles though! 
Soldered eye pins
Rings soldered together and pins starting to be soldered in place
Salt and vinegar bath to clean up the base and rings 

I honestly regret not getting a picture of the riveting process for the body and base.  It was a ridiculous two-person act.

Finally finished up after more cleaning, a patina, and final polishing.

What's next?  I'm have astrolabes and nocturnals on the mind, so either of those might be in the queue.  

- Kaley