'so must happen.
1.
The gnomon along the noon line must be pointed due north (in the Northern Hemisphere) when
set up.
2.
For a horizontal face, the angle between the face and the style must equal your latitude
coordinate. Most of you will do this.
For a vertical face, the angle between the face and the style must be the complement of your
latitude coordinate. Maybe a couple of you will try this.
The next issue is the drawing the hour lines on the face of your sundial. If the earth turns 360° in
24hours, we can conclude that the sun appears to move across the sky at a rate of 15° each hour. At the
north (or south) pole, each hour line would be 15° apart. Because we're not at one of the poles, we have
to do some calculations to find our hour lines. The following equation will give you the angle between
the noon line and a specific hour line. Solve for A for each row in the chart below. You can include more
hours on your sundial if you like, but it's not going to work while it's dark!
A= angle between the noon line and the hour (What you need to find).
L= your latitude coordinate
H= Hour Angle +15° for each hour away from noon. So, 15° for 1:00 & 11:00, 30° for 2:00 & 10:00, etc.
Tan(A) = Sin(L) x Tan(H)