How to Make a Sundial

A sundial is an ancient device for measuring time by using only the sun and its shadows. Making a sundial can be an enjoyable learning experience. Whether for fun or for a school project, you can follow these steps to learn how to make a sundial at home. 

 

 Procedure:

 Place a 2-by-3 foot flat piece of cardboard or wood in an outside spot that has full sun exposure. Be sure to choose a spot where, if you ever need to move your sundial, you can return it. This will help ensure the sundial's accuracy.

Punch a 7-inch (17.75cm) stick or dowel through the bottom center of the cardboard so that it's standing upright.If you are using flat wood, drill a small hole in the bottom center of the wood for the stick or dowel to fit into so that it's standing upright.

Mark the first hour. Put a stone or thumb tack at the top of the flat cardboard or wood surface where the shadow of the stick falls at the top of the hour in which you are beginning the recordings.

Set the timer to sound off at the top of every hour.

Write the number of the hour next to the stone or thumb tack each time the timer sounds. For example, when the timer sounds at 6 o'clock, write a 6 next to the stone or thumb tack.

Repeat this process until 13 hours are marked on the cardboard or wood.

• The pattern of stones or thumb tacks should have appearance of a semi-circle when completed. It should end with the same number it begins with. For example, if your sundial begins at 7am, it should end at 7pm.
• Depending on the time of day you begin, it may take a couple of days for your sundial to be complete. If you begin late in the day, stop when the sun goes down and begin the next day when the sun rises, marking each hour until you reach the the first mark of the day before.

Test your sundial by comparing the time it indicates to the actual time. Make adjustments if necessary.

 

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