Broken Magnets and Field Strength
Name: Breanna S.
If a magnet is broken in half, is it still as strong as if
it was whole?
Each half is less powerful, but if you simply fit them back together
I think it will be just about as good as before.
So epoxy glue or super-glue (cyano-acrylate) is a good idea,
just try to keep the glue layer pretty thin.
Glue thickness weakens the magnet by about as much as adding
an equal distance in air at one end.
For force-at-a-distance that is not much, if your glue-layer is thin.
I guess it would reduce the lifting strength a lot,
cause usually that is done with magnet-to-metal touching,
no air distance. For that you want your glue really thin.
Sometimes the shock that broke the magnet also partly de-magnetizes the halves.
If it is weaker after you glue it together than it was before, I think that is why.
"JB-Weld" is iron filings blended into epoxy.
Perfect for fixing your broken magnet.
But also mess with it sometime. Put a thick blob on a piece of paper;
it squirms some pretty odd ways with a small strong magnet underneath.
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Update: June 2012