Here we have the cheapest button compass from China, sold in a bag of 10. You can see that the red bezel is glued to a magnet with 2 pointers. The pointers should line up with the lines, but they probably don't.
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| 10pcs Mini Plastic Survival Compasses Button Design Practical Guider Accurate Compass Camping Hiking Tool Outdoora |
In this case, the magnet is off by about 15°. That sounds bad, right? But here's the good news: the magnetic declination at my location is also 15°—though probably in the opposite direction. Luckily, it’s easy to fix. If you need the display to rotate clockwise, simply rotate the magnet clockwise.
Use a compass app to confirm direction, calibrate the compass to either True North or Magnetic North for your specific location by rotating the magnet. If you travel somewhere with a different magnetic declination, no worries—you’ve got 10 of these compasses. Just scratch the correction (e.g., "15") onto the back with a nail. Once you’re satisfied with the adjustment, you can secure the magnet to the dial using a little superglue.
For the best results, choose the compass that spins most freely and stash it in your survival kit.
While this quick fix works, I highly recommend investing a bit more in a higher-quality compass for accuracy and reliability.
Pro tip: print out this guide and tuck it inside the lid of your survival tin. Place the button compass in the middle, and you’ll have a full-size bezel for reference.
