How compasses work

Learning the basics

Besides learning how to navigate the easy Silva 1-2-3 way it is also useful to know the basics of compasses. There are different types of compasses but the key feature regardless the model is the compass needle. The compass needle is placed in the liquid-filled compass housing. But there are more features – come have a look at the explanations below.

Compass accuracy

Silva is a longtime global leader in compass accuracy, precision and durability. On all Silva compasses, the direction accuracy for Magnetic North is 1 degree.

Baseline

The scales and other information on our compasses are hot stamped, which makes them exceptionally durable.

Baseplate

To make your compass last longer, we use only highly durable acrylic plastic. It is of highest quality, and it will stand the test of time as well as intense use. Also, to increase the map visibility, it has a lot of transparency.

Direction-of-travel-arrow

This arrow will point towards your travel destination after you have set the course.

Compass housing

The capsule is filled with anti-static liquid (customised formula) that ensures clear reading, fast settling time, perfect dampening, stability and accuracy of the needle.

North/south arrow

Patented red/black north-south lines in the capsule bottom ensure easy and safe settling. Align with the meridians on the map. Make sure that the map points north.

Compass needle

We have developed the world’s fastest, and most accurate, compass needle made only from finest Swedish steel. We use sapphire jewel bearing for friction free movement of the compass needle.

Clinometer

Many compasses have a clinometer built in the compass house. This is used for measuring inclination of slopes.

The scale lanyard helps estimate your travel time

To measure the map, you need a scale of some kind. Many of our compasses have scale lanyard with two scales on it; 1:25, and 1:50, which helps you measure the distance of your hike. The lanyard is soft and bendable; place it directly on the map to quickly make a judgement of your route’s distance or to plan your route in advance.

The slope card helps you stay safe in steep terrain

The slope map is good both for detecting avalanche risk and for determining how challenging the terrain is. By knowing the slope, you can also assess how much longer the distance will be due to the slope. When you are in steep terrain, you should always be aware of the avalanche risk. The risk increases if the slope is more than 30 degrees and with the slope card you can more easily assess the risk

Magnifying lens

Many Silva compasses come with a magnifying lens built into the baseplate. This is useful for reading the map and for precision map work.

Learn about balancing zones – and navigate the world!

The Earth and its magnetic zones work in mysterious ways, and to navigate accurately you need to make sure you have a compass for the place where you are at the moment. Different compasses work for different parts of the world. Hence be aware if you plan for an adventure on the other side of the world! There are three different balancing zones for compasses: Magnetic Equator (ME), Magnetic North (MN) and Magnetic South (MS). However, at Silva we also have global compasses that works in any magnetic zone.

Magnetic declination is shown on the map

The difference between Geographic (North/South map meridians) and Magnetic North (towards which the red end of the compass needle points), is called declination. The degree and the direction of declination is shown on the map.

Declination adjustment

On many of our compasses, you can compensate for magnetic declination by using the fixed declination correction scale inside the capsule. Some of our compasses are equipped with an adjustment screw for compensating the declination more permanently. A small screwdriver can be found inside the safety release of the included lanyard.