Compass polarity reversal

[dashandsaph]

Hi, just a note on compasses - mine came back from a loan with its polarity reversed and after checking it wasn't just something magnetic nearby, I was able to fix it by swiping a magnet along the length of the needle, which immediately restored it to red pointing north.

[Strider]

Nice work. Doed it matter which direction you swipe the magnet?

[dashandsaph]

No, I just swiped the magnet along the length of the needle. It worked first time, and I think I went from (reversed) north to south. It was just a fridge magnet, so it doesn't take much magnetic energy to do it. That is a bit of a worry as it means we need to be careful of how we store our compasses.

[David M]

What sort of person did you lend it to? A kid or a responsible adult? It is difficult to see how this could happen by accident. It would need to have been deliberately interfered with.

[Gusto]

I've seen this a few times before but was unaware it could be as easily repaired. It makes sense that if it can be easily reversed then it can easily be repaired.

When you place one compass above another it will skew the needles. I used to maintain a large collection of Compassess, it's common for them to be stored incorrectly, I suspect this is one of the more common ways to reverse the polarity.

[David M]

I was unaware that compass polarity reversal was a common problem. I Googled the topic and there is quite a bit written about it.

[calliejane24]

I have had this problem and was bewildered as to the cause....then realised it was due to the magnetic clip for attaching the hydration tube to the sternum strap of my pack! My compass has a longish cord but just holding it close to the clip was enough to reverse the polarity. I have since fixed it (using the same magnet) but I think I will need to remove the clip for future compass use.