Sandpaper is a sheet of paper, card, or other material coated on one side in an abrasive surface. It is a useful accessory to have when painting or decorating. The sheets are used to smooth down rough surfaces or to remove layers of paint. You are able to purchase sheets in varying grades of grit and in this guide, we look at the various options for Sandpaper Grit Grades.
Sandpaper Grit Grade
Sandpaper grades are numbered. The lower the number the more coarse or rough the sandpaper is and the higher the number is how fine the sandpaper will be. There are lots of different types of sandpaper starting at 30 grit which is classed at extra coarse going all the way to 800,000 grit which is nano fine.
Remember: The higher the number = Small grains and finer sandpaper
For painting and decorating purposes in the paint preparation stage, normally the range used is 80 to 360 grit. The following table shows the differences, please be aware that there are further options but these are the typical sandpapers used for DIY and painting purposes.
In the UK we follow the FEPA(European standard) scale of grit size grade which shows a P followed by the number, for example, P220. The grading is based on the size of the abrasive material on the sandpaper.
| Grit or Grade (P): | Normally Known As: | Uses for this Sandpaper |
|---|---|---|
| 40 | Coarse | Heavy Stripping Fast Removal of material |
| 60 | Coarse | Heavy Stripping Removes wood and materials fast |
| 80 | Medium | Light Stripping, Smoothing shallow scratches, Used for hardwood |
| 120 | Fine | Smooths, Removes small bumps and marks Starting grain for softwood General prep work Plaster patches |
| 180 | Very Fine | Finishing Preparation work for latex & Acrylic Raised wood grain Final preparation of old paint |
| 220 | Very Fine | Surface finishing Prep for wood stain Leaves a general smooth finish |
| 320 | Very Fine | Sanding between coats Wet sanding Final finish |
| 400 | Extra Fine | Polish of final coats, Smoothing Top Coats Sanding between coats Leaves smooth finish |
| 600+ | Super Fine | Sanding metals, plastics and ceramics Leaves smooth finish |
| 1500 | Ultra Fine | Final Delicate Sanding Polishing thick surface |
Sandpaper Grit Grades and Uses
The Grit grades below are a guide to the commonly found sandpapers available and thier uses. Manufacturers differ on the scale but this is the average.
P40-P50 Coarse Sandpaper
This sandpaper choice is used for quick removal of material such as paint or wood and is extremely rough.
P60-P80 Medium Sandpaper
A Medium sandpaper is widely used in paint preparation for sanding back bare wood ready for finishing. It can also be used for removing varnish.
P100-P180 Fine Sandpaper
Fine sandpaper is used for sanding back bare wood ready for coating with varnishes or paint. This choice can also help with cleaning plasterwork and removing water stains from wooden surfaces.
P220-P240 Very Fine Sandpaper
Very fine grit is used for sanding in between coats of paint and stain to flatten down the finish.
P280-P320 Extra Fine
This sandpaper helps in removing small dusts and marks between coats of paint
P360-P600 Super Fine
Very minor blemishes or small scratches in final coats can me smoothed out with super fine sandpaper.
Grit Material
As wells the grit grade the actual grit material can differ. It can be made with man-made materials such as aluminium oxide, silicon carbide or alumina-zirconia. The most commonly used is aluminium oxide. Emery and Garnet are the natural occurring materials used.
Sandpaper Backing
The grit material requires a backing for it to be glued on. Although the word sandpaper implies it would be paper it can be a variety of materials and can include rubber, polyester, rayon, cotton, PET film, cloth (more commonly used for mechanical sanding).
Further Reading: