How to Make a Clinometer
A clinometer is an instrument that measures vertical slope, usually the angle between the ground or the observer and a tall object, such as a tree or building. Clinometers are frequently used in astronomy, surveying, engineering, and forestry. While you could purchase one of these very useful tools, they are also remarkably easy to make. Here's how.
Steps [edit]
Fixed Angle (45 degree) Clinometer [edit]
- Fold a square piece of paper in half to form a triangle with one 90 degree angle and two 45 degree angles. Note that the paper must be square (all sides must be equal length). Thicker paper, such as construction paper or poster board will make your clinometer more durable.
- Tape a straight drinking straw to the triangle's hypotenuse. Position a drinking straw along the hypotenuse (the long edge of the triangle) so that one end extends slightly out from the paper, and use tape or glue to secure it to the paper. The straw will be the sight that you look through. Make sure you don't deform the straw, and make sure that it is aligned perfectly on top of the hypotenuse.
- Use a hole-punch to make a small hole close to the corner where the hypotenuse meets one of the sides. The hypotenuse, of course, meets both of the other sides. You should put the hole along the corner where the straw does not extend beyond the paper (this will be the top of the clinometer).
- Insert a string through the hole and tie a knot around the hole. Use enough string so that you have at least a few inches dangling at the bottom of the clinometer.
- Tie a washer or fishing weight to the bottom end of the string. The weight should dangle a few inches below the corner of the clinometer.
- Use one eye to look at the top of some tall object, such as a tree or pole, through the straw. Back up or move forward until the weight points straight down the string is parallel to the edge of the clinometer. When this happens, it means the angle of elevation between your eye and the top of the object is 45 degrees.
Protractor Clinometer [edit]
- Get a protractor with one straight edge (a 180 degree protractor).
- Tape a straw along the straight edge of the protractor.
- Tie a string through the small hole on the straight edge that is directly across from the 0 degree mark on the protractor. This may also be labelled as 90 degrees. If your protractor does not have a small hole here, or if the hole is not situated correctly (this is a common problem with some cheap protractors), tape or glue the string to the protractor at this mark. Make sure the string dangles a few inches below the protractor.
- Attach a washer or fishing weight to the dangling end of the string.
- Sight the top of a tall object through the straw.
- Note the number where the string crosses. Subtract this number from 90 to determine the angle of elevation between your eye and the top of the object you are sighting.
Tips [edit]
- Once you know the angle of elevation you can determine the height of the object you are sighting. To learn more about how to use a clinometer, look at the related wikiHow, "How to Measure the Height of a Tree."
- It is much easier to use these simple clinometers with two people. One person can sight the object through the straw while the other can note the position of the string.
Warnings [edit]
- Use caution when walking with the clinometer to your eye as you could poke your eye if you fall.
- If you require a very high degree of precision, you should probably use an electronic clinometer.
- If the ground at the base of the object you are sighting is on a different level than the ground you are standing on, or if the object you are sighting is leaning, you will not get an accurate measurement without adjusting your calculations.