Posted 30th Jun 2016
Sundials are the oldest of all timepieces. This home-made sundial not only tells the time, but also makes a great garden feature, especially on a sunny day
To make a sundial, you need a solid, even surface in a sunny, south-facing location, a tree stump, for example, is ideal. Our sundial only shows the hours; astronomical calculations are needed to create a sundial which is accurate to the minute.
You will need:
- A slightly angled (15 to 20 degrees) section of tree stump in any thickness (available from forestry companies and timber merchants)
- A drill
- A wooden stick twice as long as the diameter of the tree stump
- Wood glue
- A pencil
- A ruler
- Black wood paint
- Wood varnish
1 Drill a hole into the centre of the tree stump to hold the wooden stick. Angle the drill so that the hole created is at 45 degrees and deep enough that one third of the stick will slot inside. Once inserted, the stick should project over the diameter of the tree stump. Fix the stick in place with wood glue.
2 Mark out the hour scale on a sunny day: mark the shadow cast by the stick on the hour every hour using a pencil and ruler. Write the time at the end of each line. Make sure you draw the lines right up to the numbers to make the sundial easier to read.
3 Paint over the markings with the black wood paint and treat the surface of the tree stump with oil or clear wood varnish. Of course, the sundial will only work during summer time, which this year runs from 31st March to 27th October.
Or try this idea...
This stone slab is placed so that the lower edge faces north. A metal pole is positioned in the centre of the upper edge. To make the scale, fix a piece of chalk to a string. Tie the other end of the string around the pole. Pull the string taut and draw a semi-circle with the chalk. Mark the position of the pole's shadow on the semi-circle on the hour every hour. Write the numbers on stones using a water-resistant pen and affix the stones to the slab at the corresponding points using adhesive.