Fine (100- and 120-grit): The best utility sandpaper. Fine grades smooth scratches left by coarser grades and rough up painted surfaces before accepting new paint. They’re also good for sanding drywall. When you just need some for hand-sanding, or to use with an orbital sander, this is the grade you’ll most likely use. Very-fine (150-, 180- and 220-grit): This produces ultra-smooth surfaces on wood. People often use it to scuff-sand lacquer, polyurethane and other finishes before applying another coat. Using very fine grit sandpaper requires minimal pressure and careful, even strokes to obtain a uniformly clean surface. Avoiding over-sanding is also crucial, as a too-smooth surface will not accept the final paint or varnish coat. Super Fine Grits (320-600) Medium (80-grit): This is often the first grade chosen when going through the grits to prepare wood for finishing. Use it to hand sand, or with a belt or orbital sander. It’s also good for removing rust and corrosion from metal.

Sandpaper grits are also used for another type of surface smoothing: drywall sanding. Concrete Sanding In woodworking, fine-grit sandpaper is especially helpful since it helps to smooth out the wood grain, get rid of saw marks, and get the wood ready for staining or painting. They work well for removing small surface flaws, corrosion, and oxidation from metal and other surfaces.When polishing and buffing soft and sensitive materials like plastic, metal, and fiberglass, ultra-fine grits are the best choice. The Micro Grits (1500–2000)

If you need to get rid of old paint or varnish, start with a coarse grit (40–60) and work your way up to a medium (80–120) and finally a fine (320–600) sandpaper (150–220). Use a very fine grit for the final polish (240 to 600). Whether you’re working with metal or plastic, always begin with a fine grit (150–220) and work your way up to a very fine grit (240 to 600). The Sandpaper Grit Scale Extra-fine (320- and 360-grit): The first of the micro-abrasives, this is primarily for sanding finishes before polishing.

Sandpaper grit is what makes it abrasive. Manufacturers grade sandpaper based on the size of the grit, and the grade you need depends on the job.

Extra-coarse (24-, 30- and 36-grit): Generally used for preliminary hardwood floor sanding, this usually comes in belts that fit on a drum sander, or disks that fit an edger. Very minor blemishes or small scratches in final coats can me smoothed out with super fine sandpaper. Grit Material The material might become uneven and damaged by excessive sanding. Once you’ve reached the desired degree of smoothness or the last grit, stop sanding. It’s important to be patient and not rush the procedure because various materials may require varying degrees of sanding. Conclusions Because coarse and fine sandpaper grits are used differently, manufacturers established grades — each consisting of one or more grit numbers — to help consumers decide which type fits a particular purpose. The coarsest grade, designated as extra-coarse, includes 24-, 30- and 36-grit paper. The finest grade (i.e. ultra-fine) includes 800- and 1,000-grit paper. Furthermore useful for shaping and smoothing off jagged edges on materials like stone, masonry, and concrete are coarse grits. It’s crucial to use finer grit to get rid of those scratches and provide a smoother finish because they could leave deep scratches on the surface.