How come Mareiner boards are so often found at the best residential and commercial addresses? We assume it's because of their smooth appearance. After all, we use different coarse and fine grinding brushes to get the finish just right. We use them to roughen the planed surface of the wood to a superfine finish. It makes for better paint bonding and also allows glazes and oils - the skin care lotions for any self-respecting board - to penetrate deeper into the wood.
We roughen the surface a little with grinding brushes of different grain strengths to achieve a better adherence of paint to the wood.