Compensation for Magnetic Declination

There are two primary ways of compensating for Magnetic Declination.

• Calculate the difference between True, Grid and Magnetic Declination using math (See Magnetic Declination)

• Use a compass with adjustable declination (See Adjustable Declination Compass)

Marker Hack

Use a very find permanent marker to make your own "Doghouse" on your compass capsule.  This works fine but has a few drawbacks over compasses with adjustable declination.

Drawbacks:

• It's hard to draw perfect lines on your compass - find someone who is good at this

• Declination changes ever year, so you will need to update your lines or deal with outdated lines

• If you go to a different part of the world, such as an out of state High Adventure, you will need to remark your compass

Magnetic Grid Hack

Maps used for Orientation Competitions come with Magnetic North lines already printed on them so participants can focus on strategy and speed to find points without having to factor in math.

You can use a ruler or yardstick to make your own Magnetic Lines.

When using your map, line up the orientation lines on your compass with the Magnetic lines instead of the grid lines.