The method as given seems to work properly on the thigh of Posette, but not on other figures. After a little experimenting (on Misaki's arm), I think you can make it work by these steps: (1) shrink the magnet itself until you can see a pinch; (2) expand the Mag Zone and move it on the Y axis (toward and away from the body) until the pinch looks right. You'll still probably need to add a 'plug', like a simple ball prop scaled and colored to match.

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