Inter-coat sanding is an essential step in woodworking and the paint finishing trade. After the primer or filler has dried completely, raised fibres, dust particles and runs are sanded smooth using fine abrasive paper of grit 180 to 240. The sanding must be shallow enough not to expose the substrate. All sanding dust must then be completely removed with a tack cloth or compressed air before the next coat is applied. Inter-coat sanding not only improves the visual result but also significantly increases the mechanical adhesion of the subsequent coat through a defined micro-roughness. In vehicle body finishing, it is indispensable for high-quality top coats.