Masking tape works but DUCT tape is even better. I use it to clean chips and debris off all my magnetic tools when needed.
And ALL the chips wind up in the trash bin, along with the tape. No secondary clean-up.
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It will soon attract swarf. I use switchable/ on-off switch magnet, though more expensive, but gives me peace of mind.
Do beware vacuuming the metal causes electrostatic effects. If combined with cellulose, Al, or Mg there'd be a fire hazard, no?