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COMPLETELY MYSTIFIED BY THIS MAGNET ? AND A 12-PACK DIDN'T HELP!!!

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ColinPearson

ColinPearson

Petroleum
May 1, 2011
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Hey folks... I'm hoping someone can shed a little light on this question for me. New to the magnet forum here, it's not at all an area that have experience in. But, let me 'splain the situation:
My friend has a 5th wheel trailer; if you're familiar with those then you'll know they have belly boxes for storage underneath. The doors to these storage areas are help up/open by either spring-loaded clips or magnets; his are magnetic. The magnetic "latch" is a pair of magnets, N to S i.e., not one magnet and an opposing piece of metal. One is mounted on the door and one on the side of the trailer. The ones on the door are mounted right at the frame fo the door panel which I assume is a piece of tubular aluminum with plastic, insulation and fiberglass jacketing the framing.. The left hand side (L)stuck quite well but he pair on the right hand side (R) were pretty weak so he decided to replace them. Off to the store he goes, comes back with new magnets and installs the new pair on the right. Now the (new) R pair works well but the (existing, previously working) L totally stopped sticking together. Any idea what in the world is going on here? We drank a 12-pack on the matter but still can't think of anything. Please help ease our weary brains! And thanks :)
 
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the pic does not tell much of story. a picture or a schematic showing the arrangement of magnets, the polarities is useful.

my gut guess was the magnetic flux was shunt away. Did you use any steel in your doors?
 
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As I said, I'm kind of ignorant in this field, could you help me ID which pole is which? That pic is unfortunately the best I have. The doors very likely have metal framing, roughly where the black edging is around hte perimeter (of the door and it's opening. That said, I would *think* it would be aluminum as they try to keep these trailers as light as possible, but I'm not sure. Either way, the two left hand circles are highlighting a N/S pair of magnets; same for the pair on the right, but I'm not sure how to tell which is which. At any rate, both door-side magnets are one pole and the other two are opposite. Does that help at all?
 
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Sounds like you either have the polarities reversed, or you lost magnetic properties (dropped, went thru degauser).

Have you removed the offending magnet and seen if it will "latch" on to the other magnet?
 
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The L (previously working) pair was untouched but stopped working after installation of the (new) R pair. The (new) R pair was sticking fine before and after installation. ALSO IMPORTANT AND I FORGOT: the (previously NOT working) R pair that was removed DOES stick to themselves just fine once they were removed.
 
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Taking the door-side magnet from R off, it will stick to the wall-side magnet on L, but repels the door-side magnet on L (as I would have expected).
 
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IRstuff - no, we only replaced the R pair. I will ask him to double check the spacing though, could be as simple as that.

prex - After looking at spacing, I'll also have him do this.
 
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monkeydog - a fair question! But it was mostly before said 12-pack LOL

Update: The fit/contact between both pairs is good. I checked with my buddy and asked if we could rotate one of a pair by 180°, but he said that he tried that before installing and put them in the way were they stuck the best. Asked about swapping the positions of one pair (R door to R wall and vice-versa) and he didn't want to for fear of stripping out the holes. Can't blame him for that as RVs/campers are not really known for their quality of construction.

I'm stumped!
 
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