TIME - FALL 2025 - Jeffrey Feddersen
01 Sundial
To understand how a sundial works, I found some useful information on Shadows Pro and Horizontal Sun Dial YouTube Video to incorporate in my design.
Here are a few key points:
- Solar time: the degree on a surface for each hour equals to 360°/24 h = 15°/hour
- Location: Northern Hemisphere, Brooklyn New York
- I used the shadow software to give me data regrading the relationship between the sun and my current location
When I first started making the sundial, I put 15 degree increments between each hour. Which is how much the sun would move on average when looking in the celestial sphere. I used 40.6 degree as my style height since Brooklyn sits at about 40.6°N latitude.
I also read about solar angle calculation. Since the sun is moving in a three-dimensional space, but the gnomon is casting on a two-dimensional surface, so there needs to be a solar angle adjustment for a horizontal sundial(at least that’s how I understood it…correct me if I’m wrong).
So I used the ShadowPro software to generate a diagram of the solar angles based on my location in Brooklyn, New York.
I then brought the reference image into Fusion, and mapped the angles to my disk. I then adjusted the style ratio to fit my disk, and created an indent for the style to sit in place. Since the material would be plastic, I extruded the grid to have a more apparent look.
My original gnomon was a right triangle, but I realized after my conversions length might be too small for it to cast onto my hour lines, so I made another adjustment to make it longer.