Mechanical Dialing and a Laser Trigon
The most popular ways to lay out sundials involves computation, geometry, or a combination of both. These methods assume the dial will be created on a regular surface, such as flat horizontal or vertical dials or circularly curved equatorial dials.
A less known method is mechanically drawing dial lines using a string or laser beam to project artificial “sunbeams” to show where light and shadow fall. This technique can be used on both regular and irregular surfaces. We start by describing the principles of a trigon.