BandSand Bandsaw Sandpaper Tips
Extrafine. This sandpaper is best used between coats of paint or varnish. Grits of 240, 320 and 400 are termed very fine, while extra or superfine sheets with grits of up to 600 are available for polishing jobs.
Fine. Fine abrasive papers have a grit in the range of 120 to 220. For most home workshops, fine will suffice for final sanding before the work is finished.
Medium. Some final shaping can be done with medium, which has a grit range of 60 to 100. General sanding work is often best done with medium-grade sandpaper.
Coarse. Rough shaping is the strong suit of coarse paper, as is the removal of previous finishes. The grits are typically in the 40 to 50 range.
Extra coarse. Mostly used for removing paint and varnish that you think might never come off. The sanding of old floors too, sometimes requires the abrasiveness of extracoarse sandpaper. Don’t even think about using it on any but the toughest jobs.
- #50-#30: Very Coarse Grit – Rips off peeling paint and extraneous materials with ease. Also, risks damaging your project. Not recommended for fine pieces such as trim or furniture.
- #80-#60: Medium Grit – Your universal grades of sandpaper. It is hard to go wrong with sandpaper grits in this range. You can work down difficult materials by applying more pressure to your workpiece. Or, you can preserve fine materials by letting up on the pressure.
- #180-#100: Fine – You would never use these grades of sandpaper on the first run-though. Grits in this range are always for second or third sandings. Sometimes, fine grit sandpaper is used to “roughen” down glossy paint in preparation for applying another coat of paint.
Grit size refers to the size of the particles embedded in the sandpaper. Several standards have been established for grit size. These standards establish not only the average grit size, but also the allowable variation from the average. The two most common are the United States CAMI (Coated Abrasive Manufacturers Institute, now part of the Unified Abrasives Manufacturer’s Association) and the European FEPA (Federation of European Producers of Abrasives) “P” grade.
Below you will see we use European FEPA (“P” Grade) for our standards.
The weight of the backing is designated by a letter. For paper backings, the weight ratings range from “A” to “F,” with A designating the lightest and F the heaviest.
Letter nomenclature follows a different system for cloth backings, with the weight of the backing rated J, X, Y, T, and M, from lightest to heaviest. A flexible backing allows sandpaper to follow irregular contours of a workpiece; relatively inflexible backing is optimal for regular rounded or flat surfaces. Sandpaper backings may be glued to the paper or form a separate support structure for moving sandpaper, such as used in sanding belts and discs. Stronger paper or backing increases the ease of sanding wood. The harder the backing material, the faster the sanding, the faster the wear of the paper and the rougher the sanded surface.
Sandpaper with paper backing: