History :
, also known as midsummer, occurs when one of the Earth’s poles has its maximum tilt toward the Sun. It happens twice yearly, once in each hemisphere (Northern and Southern). For that hemisphere, the summer solstice is when the Sun reaches its highest positionin the sky and is the day with the longest period of daylight. Within the Arctic circle (for the northern hemisphere) or Antarctic circle (for the southern hemisphere), there is continuous daylight around the summer solstice. On the summer solstice, Earth’s maximum axial tilt toward the Sun is 23.44°. Likewise, the Sun’s declinationfrom the celestial equator is 23.44°.
Since prehistory, the summer solstice has been seen as a significant time of year in many cultures, and has been marked by festivals and rituals. Traditionally, in many temperate regions (especially Europe), the summer solstice is seen as the middle of summer and referred to as “midsummer”. Today, however, in some countries and calendars it is seen as the beginning of summer.
How to Build A Sundial for the Garden
Begin the project by cutting a 20-inch diameter circle from 3/4-inch plywood. Give both sides two coats of primer. While it is drying, start planning a design for the sun dial face. You will choose colors, number style (Roman numerals, standard, etc.), and some kind of illustration you like. Draw some designs you like on a large piece of paper. You’ll need a compass, straightedge, and protractor to place the hours correctly. Each hour must be located on a circle exactly 15 degrees from the next hour.
When you’ve decided on the design, use the paper as a stencil and paint it onto the plywood circle and put on the design numbers, hour lines, and illustration. ttps://www.blocklayer.com/sundial-popeng.aspx
Gnomon
The gnomon is a two- or three-inch length of threaded pipe, one half-inch in diameter. It, like the flange, will rust if not painted. The diameter of the gnomon should be a little wider than the pipe’s, and you’ll need to improvise a conical tip for it. The total length of the pipe and the gnomon tip should not be more than three inches.
Preparing the Post
To make the sundial work correctly, it must be properly mounted on a carefully prepared and placed post. Use a 4 by 4 by 8 pressure-formed, outdoor-treated post. Make sure it is straight and free of large cracks. The 4 by 4 must have a carefully measured and cut angle at the top, in order to mount the sundial face correctly. To find the angle, subtract your latitude from 90 degrees. That line becomes the bottom side of the angle. Now you are ready to measure the angle and cut it.
Use a protractor. Then cut it off as pictured. Ideally, make the cut with a table saw for exactness, and check the slanted face with a square.
Locate the center of the sloping face, and pre drill the center hole in the post. The 5/16-inch lag screw will penetrate the post to a depth of about 1-1/4 inches. Drill an additional hole in the center of the plywood sundial face to let the lag screw pass through before going into the post. Perform a trial attachment of the sundial face to the post with the lag screw.
Choose a sunny spot for your post. Don’t put the top of the post more than five feet above the ground.