Steps and process of making sundials

The steps and process of making a sundial are as follows:

1. First, take the center of the third part of the cardboard and draw a circle with a diameter of 10 cm with a compass. After the front is finished, take the center of the same compass on the back of the cardboard and draw a circle with the same size. Then draw a 9 cm concentric circle on the front and an 8 cm concentric circle on the back.

2. You can use a protractor to take points on the largest circle every 15 degrees, and the paper jam can take points on the front and back circles at the same time.

3. Draw positive and negative figures on the cardboard according to the standards of the sun and summer, and the negative figures are counterclockwise from small to large.

4. Draw a horizontal line on the front quarter of the cuboid foam, then draw two vertical lines on the horizontal lines on the two sides of the long square, and then draw a diagonal line with an angle from top to bottom on the quarter of the two sides of the cuboid, which is the local latitude value.

5. Take a paper cutter, press it on the horizontal line of the front, cut it down along the diagonal of the side, and cut it in half. Then insert the foam into the lower part of the card paper made in front along this diagonal plane, and insert a toothpick into the center of summer as a pointer. This is a summer.

Matters needing attention in using sundial:

When using a sundial, no matter what form it is, there is an hour hand. The angle between the hour hand and the ground plane must be the same as the local geographical latitude, and it must point to Polaris correctly, that is, there is a pointer parallel to the earth's rotation axis. By observing the projection of this pointer on the designated area, the time can be determined.

According to the laying angle of masonry surface, it can be divided into horizontal type, vertical type and equatorial type. Because the sundial must rely on sunlight, it can't be used on cloudy days and nights. Therefore, it is not enough to use the sundial to time, and other kinds of timers, such as water clocks, are needed to cooperate.