Use a Compass

How to use a compass

Use a Compass

Almost all of us carry instantly updated maps and GPS systems in our pockets these days in our phones, reducing the threat of being lost to almost nil. But what would happen if you didn't have your phone, or the battery died, or your Tom-Tom took a swim? What if you just don't get any signal where you are? Lets look at the old fashioned, never-fail navigation tool: the humble compass.

Learning how to use a compass is really easy. Its usually used together with a map, but it doesn't have to be. A compass will always tell you which direction is North, West, South, and East.

There are thousands of types of compasses available. We prefer two types: a Lensatic compass like the military uses, and an Orienteering compass which is simple to start with. Lets look at how they work.

Pointing North

See the red arrow in the photo below? It always points towards magnetic north. (Just make sure its not near any large metal objects or magnets, or it might not since the metal may affect the sensitivity of the small magnet in the compass needle.)

How To Use A Compass

But wait, you say. The compass needle in the photo isn't pointing toward the N on the dial. That's because the arrow is facing North but the dial on the compass isn't. If you were holding this compass you could turn your body so the arrow is under the N. Now you are facing north.

Say someone tells you to head West. Look at the compass. Turn your body (not the dial) until the compass needle is pointing to the N. Then look to your left. That's West! If you look to your right, that's East. Behind you is South.

Congratulations, you now know how to use a compass. Wasn't so hard was it? Grab one and play with it. Try figuring out what directions things are around your house or yard.

NOTE: there is a difference between the Magnetic North Pole and Geographic North Pole. The compass needle points towards magnetic north pole. The magnetic north pole is not located under the geographic north pole. And its moving! The difference in degrees between magnetic north and true north is called the declination. That's an advanced topic and necessary when using a map, or when navigating towards the earths poles. Read the Wikipedia links above if you want to learn more about those concepts.

Degrees

But wait! you say. What are all the little numbers on the compass face for? On the Cammenga the red numbers are degrees.(The black are mils, you can mostly ignore them.)

A compass is nothing more that a circle. A circle has 360° degrees. Do you remember degrees from school? 90°, 180° and so on? If not you might want to brush up here. You can use degrees to keep you on a specific course as you move from place to place. They can be used with a map to plot your course between two objects. This works because the Compass Needle will always face the same direction, North, so you have a reference point to be able to orient the degrees listed on the face and stay on track.

How to use a compass

Example One

Here's how it works. Lets say we are using a Cammenga Lensatic Compass. Open it up, and wait for the arrow to point North. Look out from where you are standing. Pick some landmark that isn't directly N, W, E, or S from you. Turn your entire body to face that direction.

Now turn the dial on the face of the compass so that the small white line #1 lines up with the compass arrow as it is in the photo. The black line #2 should be facing in the direction you want to go. Now look at the number underneath the black line, where the #3 is. That is your bearing. In photo above its 105° degrees.

You should write that down to remember it. So if you wanted to head in that direction you would make sure that you kept the #2 black line on top of the 105° marking as you are moving. Once you set the dial and the #1 white line DO NOT MOVE IT until you are done navigating. You will lose your bearing based on where you were when you set it.

This requires practice! Go outside and try it and move around so you get the feel for how this works. Its simple but might be a new concept for you and will take a couple of tries to get used to it.

Cammenga Lensatic Compass

Cammenga Lensatic Compass

Typical Price: $45

See more info on Amazon.com

This becomes helpful when you get directions from someone. Say you are at camp in the woods. A friend says that there is a river near by but there are no trails to get to it. He tells you that its at 60° degrees from where you are standing.

Open the compass, and turn the dial so the #1 line is lined-up with the arrow facing north. Now look down at the dial and look for 60°. Turn your body until the #2 line is over the red 60° marking, and walk in that direction! Great, but how do you get back? Well, add 180° degrees to 60° and you get 240°. That's your heading home. (If your initial heading had been greater that 180°, say it was 200°, then you would instead subtract 180° to get a new bearing of 20°.)

There and back again

If you are using an Orienteering type of compasses like the Suunto A-10, its even easier because you don't need to remember any degrees or numbers. This is probably the best type of compass for a beginner, although its not as durable as the Cammenga so its not our first choice for a BOB. However we also think you should have a backup compass, either in a family members bag or in yours and the Suunto is a nice light-weight option.

How to use a compass

Example Two

Lets say you are staying in a cabin and are heading out to the woods. Point the Direction-of-Travel arrow #1 towards them. Now adjust the dial #2 so that the red arrow #3 is under the compass arrow #4. The compass needle will point to the N on the dial, indicating North.Now start heading in the direction of #1 direction-of-travel arrow. As long as the #4 compass needle stays above #3 you are heading in the right direction.

If you lose sight of where you are going no problem. Hold the compass, orient it (#4 over #3) and find a landmark close by in that direction and head towards it. Keep this going until you arrive at your destination!So how do you get back? Easy! Just turn the compass around to face you. So the direction arrow #1 is now pointing at your chest. Just make sure #4 stays over #3 and head home! DON'T TURN THE DIAL! Super simple.

Suunto A-10 Field Compass

Suunto A-10 Field Compass

Price: $18

See more info on Amazon.com

There are a few other concepts to learn about if you want to truly learn how to use a compass: how to read and navigate using a map, and understanding declination. We will get into those subjects at another time.You can also carry a compass with you anywhere you go with a watch like the Timex Expedition I wear everyday.

For further reading we suggest you check out Bjorn Kjellstroms book Be Expert With Map & Compass: The complete Orienteering Handbook. And go out and practice! 

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