Help! Compass 180 deg out!

Forest Girl

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Had to remove my Plastimo compass to get at the Whitlock steering. I accidentally used a magnetic screwdriver to remove screws. Not sure if this caused it but compass is now 180 deg out. Any sensible suggestions on how to rectify problem greatly appreciated.
 
If I'm right in assuming this is a Plastimo Contest ' porthole ' compass readable from both in and out of the cockpit, there should be a small rectangular black plastic tray just underneath the globe with the corrector magnets; my first check would be to see that's in place.

Edit - ! 180 out, is it back in the right way ?!
 
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If I'm right in assuming this is a Plastimo Contest ' porthole ' compass readable from both in and out of the cockpit, there should be a small rectangular black plastic tray just underneath the globe with the corrector magnets; my first check would be to see that's in place.

Edit - ! 180 out, is it back in the right way ?!
it was possible to inadvertently do that with a bosun type grid compass.
does this compass have a hood /cover that pivots over, it could well be the wrong way round
 
Now you're dating me, the first boat I ever sailed had a Bosun compass; a good bit of kit but required ' head down ' peering at while not looking out, also tended to get trodden on.

Looked the part though;

sorry for thread drift.
 
Had to remove my Plastimo compass to get at the Whitlock steering. I accidentally used a magnetic screwdriver to remove screws. Not sure if this caused it but compass is now 180 deg out. Any sensible suggestions on how to rectify problem greatly appreciated.

It might help to understand the problem if you could post a photo and identify the exact model
 
Unlike Seajet I'll assume it's a binnacle compass as it's on a steering pedestal. Have you taken the compass off its base? The magnets for correcting N/S and E/W accessible under the circular plastic plugs need to be in the correct orientation. From memory standing behind the compass looking vertically down the E/W should be nearest you and the N/S on your right.
 
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Now you're dating me, the first boat I ever sailed had a Bosun compass; a good bit of kit but required ' head down ' peering at while not looking out, also tended to get trodden on.

Looked the part though;

sorry for thread drift.
I still use a Bosun's compass!
 
I still use a Bosun's compass!

So do I . I have two positions for it. One at the front of the cockpit and one , with illumination, under the tiller. Does not get kicked or trodden on there.
The mounting and gimbal has to be flipped over when moving from one mounting to the other but I don't see how it can be made to read 180° out as suggested earlier.
 
When something similar happened to the compass on the 'Pequod' Captain Ahab fixed it with a harpoon, a top-maul, some linen thread and a sail needle. Surely you must carry these things on board? :)
 
Pretty certain that the same thing happened to me about 20+ years ago. If I remember correctly, I'd put it down and it fell over and then read 108 deg. out. Nothing to do with the removable deviation adjustment magnets in my case. It was just a matter of the floating compass section turning upside down and coming upright 180 deg. out. I fixed it by holding it upside down and turning the body around around before bringing it upright again. Difficult to describe but pretty easy to manage.

I'm guessing that the same thing has happened here. i.e. The lubber line is now on the wrong side of the floating part.
 
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Perhaps the compass has read what the BBC say about how they work:

"... the Earth acts as if it has a bar magnet running through it with the magnet's south pole located near the planet's geographic north. Since opposites attract the north pole of a magnetised needle is attracted towards it."

Not quite how I might have worded it but basically correct surely?
 
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Not quite how I might have worded it but basically correct surely?

No, it should say:

"... the Earth acts as if it has a bar magnet running through it with the magnet's north pole located near the planet's geographic north. Since opposites attract the north seeking pole [the south pole] of a magnetised needle is attracted towards it."
 
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