The problem is static electricity. If you take a wide, soft brush and beat the bristles on the edge of a metal object, it will build up a charge in the brush. You want the charge on the brush to be stronger than the charge on the model. Brush only once, and repeat the beating before each pass.
An (extreme) alternative is a "Static Master" brush, used in a photographic darkroom. These are "mildly" radioactive, and require special care, handling, and disposal.
After dusting, you can lay the model on an anti-static cloth, such as those used for dusting T.V.s & computer monitors.
Hope this helps !