The formula is quite simple: reverse the magnetic field so that, instead of being welded together, the two halves repel each other like opposing magnets.
(the two halves; repel; each other) Context(the two halves repel,List([99, 119))):(the two halves; repel each other like opposing; magnets)
the two halves repel,List([99, 119))
the two halves the two halves
repel repel each other like opposing
each other
magnets