Model Sundial
From DT Online
Introduction
Sundials (or Shadow Clocks) are perhaps the oldest scientific instruments. They are thought to have been developed by the ancient civilisations of Babylonia, Egypt, Greece and Rome. They were used by Viking and Medieval navigators and are still in use today.
One of the most common types of sundial is a Horizontal Sundial and a fully working model can be constructed using Stripwood Technology materials and techniques. Sundials are based on the apparent movement of the Sun across the sky. Making a model can lead to an understanding of our Solar System and terms such as Latitude.
Sundials have two basic parts: there is a sloping rod (or edge of a plate) which casts the shadow and plate, or 'dial', on which the shadow falls to indicate the time. The sloping rod is known as a Gnomon. The Gnomon should always point North (in the northern hemisphere) and be set at an angle which is equal to the Latitude of the Sundial's location.
Preparing the Materials
- To make the Gnomon, cut a right-angle triangle out of Thick Card which has the Sundial's location Latitude set as one of the oher two angles.
- Position the card Gnomon vertically down the centre of a sheet of A4 Thick Card such that the right-angle is uppermost (i.e. fix along the Hypotenuse).
- Glue lengths of Stripwood along each side to secure it.
- The A4 Thick Card will form the 'dial' of the completed Sundial.
Setting Out the Hour Lines
Completing the Model Sundial
- Structures and Frames can also be modelled using the Construction Kits listed in the Truss Bridges and Looking at Bridges articles.
Safety Point! Take great care with hot glue guns and all hot-melt glues. The melted glue can stick to the skin and cause severe burns.
 
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| Junior Hacksaw
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Clamp-on Hobby Vice
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Stripwood
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Balsa Wood
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Medium card coloured
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Thick card coloured
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Cutting Mat
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10mm Squared Paper
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PVA glue
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Glue Gun
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Bamboo Flower Sticks
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Notes:
- Choose metal cutting hacksaw blades - the teeth are small which suits this scale of work and they are safer for young children
- School PVA glue is best for young children because it is non-toxic and washes off : PVA Wood Glue is strongest but must be used with care.
- Try to get natural Flower Sticks or wear gloves because the green stain comes off on hands!