Bubbles in your compass can make you want to just break through the window and pop them. Compasses are navigational instruments consisting of thin, magnetic metal encased in plastic or glass. A compass is usually filled with water or compass oil, which is a mixture of water and white spirit. Bubbles usually emerge in compasses as a result of drastic atmospheric pressure changes or a slight leak in the housing material. While bubbles do not usually affect the performance or accuracy of the compass, they can grow annoying to look at -- especially if your tool is costly.
Inspect the seal around the circumference of your compass for signs of leakage. Signs can include traces of moisture, an uneven seam or mineral deposits. If you find any of these, your compass should be professionally repaired or replaced.
Place the compass on a sunny windowsill if you can't find any obvious signs of leaks. Leave it undisturbed for two to three hours.
Remove your compass from the windowsill once the bubbles have disappeared. Warmth from sun exposure causes the liquid to expand and fill the bubble.
Locate the filling screw on the side of the compass. Depending on the type of compass you own, the screw may be located at the rear.
Tip the compass carefully to access the screw. Loosen and remove it.
Insert the tip of an epoxy syringe into your container of new compass oil. Pull up on the syringe plunger to collect the oil.
Place the tip of the loaded syringe into the filling port. Depress the plunger to inject the oil into the compass. Agitate the compass to distribute the newly added oil and remove any remaining air pockets.
Replace the filling screw and tighten it using a screwdriver. Return the compass to its original position.
Compass oil can be purchased from compass manufacturers or camping equipment retailers. Boat and maritime equipment retailers may also carry compass oil. You may need to repeat step four in section two several times to remove the air bubble completely. If a bubble continues to reappear in your compass, you may need to have it professionally serviced or replaced.