Attached Link: http://www.morphography.uk.vu/magnets1.html

My tip is: don't place or size the magnet. I never do. Set the element display property for the magnet and base to outline so they don't get in the way. Forget the magnet analogy altogether, in fact. All you need the magnet itself for is to control the eventual deformation of the mesh, and all you need the mag base for is so you can save and/or delete the thing when you've finished with it. The thing to concentrate on is the mag zone - that's what determines the magnet's sphere of influence (literally). Get that positioned correctly, and scaled correctly, and you're most of the way there. I often set the zone's display property to wireframe so I can see it easier.