Horizontal Sundial Designer
From DT Online
Horizontal Sundials are positioned on a flat level surface.
Features and Applications
The Dial is positioned horizontal relative to its location on the Earth's surface, which means it must be Tangential to the curve of the Earth and set such that its Gnomon points to True North. A simple geometric analysis will reveal that if the Gnomon is to remain parallel to the Earth's vertical axis, it must be set at an angle to the horizontal Dial which is equal to the Latitude of its location.
- Click on the pencil-shaped Edit icon below to show or hide variables and click inside table to alter values (scroll to see all).
- Left or Right click on the screen display or use Scroll Wheel to alter view and Left click on Zoom icon to restore (note: Zoom will be focussed around the cursor position)
- Left click on Download icon and Open with your preferred browser then print screen image from there (useful for trying ideas for text and graphics etc. but unlikely to be actual size), or Save File to create a full-size Scalable Vector Graphics (svg) file which can be loaded into LibreOffice Draw and printed, or graphics software such as Inkscape for eventual output at actual size to a Plotter/Cutter for example. See Packaging Designer User Guide for more detail.
- In the table below, enter the Latitude of where your Sundial will be located.
- Since the main purpose of this Sundial Designer is to establish the correct angles for the Hour LInes, a simple screen Print-out will often be sufficient to transfer these on to your actual 'Dial Plate'.
- Alternatively, the table also provides the number of degrees for each Hour Line away from the Noon position and can be marked out directly on to your 'Dial Plate' material.