Capricorn: Dec.22-Jan.29 The Sundial Primer
created by Carl Sabanski
Capricorn: Dec.22-Jan.29

The Sundial Primer Index

DeltaCad Sundial Macros - Valentin Hristov - Polar Nodus/Gnomon Box Sundials

Here are a couple more box sundial macros written by Valentin. Because a nodus is used to give the shadow, it is possible to use these sundials as a compass. Simply rotate the sundial until the nodus shadow falls on the corresponding date line and then the main direction of the dial will be true North-South.

Polar Nodus Box Sundial - sdboxnp

This box sundial is generated after the user enters the "Latitude", "Longitude" and "Central meridian" of the sundial's location as shown in Figure 1. A "Place" descriptor can also be included. Time or hour line intervals of 15, 30 and 60 minutes are available. The hour lines can be adjusted for longitude and the Equation of Time. Longitude correction can be removed by entering the same value for "Longitude" and "Central meridian". The sundial covers a period of half a year. Two sundial drawings, one for each "Period", must be generated to cover the entire year.

Figure 1 - Polar Nodus Box Sundial Macro

Figure 1 - Polar Nodus Box Sundial Macro

The sundial drawn with this macro is shown in Figure 2. 

Figure 2 - Polar Nodus Box Sundial

Figure 2 - Polar Nodus Box Sundial

Two sets of hour lines are drawn, one for the morning hours and one for the afternoon hours. There are two sets of hour numbers. The blue indicate standard time and the red indicate Daylight Saving time. There are two sets of small diamonds visible in the drawing. When cut out each set will form a nodus.

Figure 3 shows a photo of the completed sundial.

Figure 3 - Polar Nodus Box Sundial Model

Figure 3 - Polar Nodus Box Sundial Model

Polar Gnomon Box Sundial - sdboxogn

This box sundial is generated after the user enters the "Latitude", "Longitude" and "Central meridian" of the sundial's location as shown in Figure 4. A "Place" descriptor can also be included. Time or hour line intervals of 15, 30 and 60 minutes are available. The hour lines can be adjusted for longitude and the Equation of Time. Longitude correction can be removed by entering the same value for "Longitude" and "Central meridian".

Figure 4 - Polar Gnomon Box Sundial Macro

Figure 4 - Polar Gnomon Box Sundial Macro

The sundial drawn with this macro is shown in Figure 5. 

Figure 5 - Polar Gnomon Box Sundial

Figure 5 - Polar Gnomon Box Sundial

Two sets of hour lines are drawn, one for the period 21 Dec 21 Jun and the other for the period 21 June 21 Dec. There are two sets of hour numbers. The blue indicate standard time and the red indicate Daylight Saving time.

Figure 6 shows a photo of the completed sundial. Be careful to glue the gnomon as shown.

Figure 6 - Polar Gnomon Box Sundial Model

Figure 6 - Polar Gnomon Box Sundial Model