By Kathryn Vera
Updated Mar 24, 2022
lenalir/iStock/GettyImages
Steel or ceramic magnets can lose their strength if they’re stored improperly, dropped repeatedly, or simply age. The most reliable way to restore these magnets is to use a neodymium magnet, whose powerful field can realign the magnetic domains.
Touch the north pole of the weak magnet to the south pole of a neodymium magnet, then the south pole to the north pole. Repeat if necessary.
Select a neodymium magnet that clearly displays its north and south poles. Bar or rectangular shapes are ideal because they make polarity easy to identify. Avoid the most powerful grades unless you’re trained in safe handling—strong fields can snap steel objects together or damage electronics.
Use a small compass to locate the poles if they’re not pre‑marked. Bring the compass close to each end: the needle points toward the north pole when near the magnet’s south, and vice versa. Mark the poles with a felt‑tipped marker for future reference.
Place the north pole of the old magnet against the south pole of the neodymium magnet. Then switch sides—touch the old magnet’s south pole to the neodymium’s north. For magnets that have been heavily demagnetized, repeat this process several times to reinforce the alignment of magnetic domains.
After remagnetization, store magnets with alternating poles (north to south) so they attract one another. This arrangement reduces stray fields and helps maintain their strength over time. Avoid piling magnets with like poles facing each other, as this can accelerate demagnetization.
