What should you consider when choosing grit size for sandpaper?

When choosing grit size for sandpaper, the desired smoothness of the finish is the most crucial factor to consider. Different grit sizes will yield different surface finishes. Coarse grits (like 40-60) are used for rapid material removal and are ideal for shaping or leveling surfaces. As the grit size increases, the abrasiveness decreases, leading to a smoother finish. Fine grits (like 220 and above) are typically employed for final sanding to achieve a smooth surface that is ready for finishing.

While the thickness of the wood, type of finishes used, and weight of the wood may influence overall sanding techniques or approaches, they do not directly dictate the choice of grit size as effectively as the desired smoothness does. The main goal is to select a grit that will provide the finish quality you are looking for on the specific project being undertaken.