For a painter, sandpaper is not an afterthought. The difference between a mediocre and an excellent finish often lies not in the paint itself but in the preparation. A few practical insights.
Interlayer-sanding: adhesion makes the difference
Every paint layer must be sanded between applications. This mechanically increases the surface area and ensures adhesion — without it, the next layer can lift off. Use P220–P280 for interlayer-sanding on primed substrates.
Choose sandpaper with dust extraction
Mesh and perforated paper (such as BCG NET or velcro mesh) channels dust away directly through the holes. This keeps the paper cutting longer, reduces dust clouds and gives a more consistent result. For paint and lacquer work, this is not a luxury but an efficiency gain.
Use the right backing
For hand sanding: always use a sanding block. Without a block you apply uneven pressure with your fingers, which creates waves and irregularities in the surface. A hard block for flat surfaces, a soft interface for curves and profiles.
When to replace?
Sandpaper that no longer cuts but instead glazes works against you: it polishes the substrate smooth rather than creating an adhesion profile. Cheap sandpaper that wears out twice as fast eventually costs more. Calculate the cost per square metre of surface sanded, not per sheet.