All About Sandpaper and What You Should Know

Sandpaper In General

Sandpaper is essentially a piece of fiber, whether cloth or paper, that has some sort of abrasive material attached to it. Original sandpaper was shells, rocks, or actual sand attached to a material like cloth using sap or another sticky substance. Today, the backing is normally paper or cloth and the abrasive is either aluminum oxide or silicon carbide. They allow manufacturers to have significantly more control of the overall grit of the product than what was able to be had with original sandpapers. 

Sandpaper was created with the purpose of being used to smooth out the surface of a product. It can take a rough piece of wood and with enough different grits, time, and effort can get that piece to a smooth finish. Different types of sandpaper have been created to be used on most any type of surface that one would want to have smoothed out. 

Sandpaper Grit

The texture of sandpaper is determined by its grit, the coarseness of the material used for it. Grits range from the coarsest of 36 to the finest of grits in the 1000s. The grit of sandpaper is determined by the size of the sieve used to sort through the abrasives. A 100 grit sandpaper was sorted through a sieve with 100 slots per square inch and so on and so forth for other grits. The common understanding for the use of sandpaper is that coarse sandpaper is best for removing material. The finer the sandpaper, the less material you can remove at once, this makes that paper better for detail work or getting to a smoother finish. 

Sandpaper Material

The type of abrasive material varies depending on the material the sandpaper will be used on. A common abrasive for woodworking in particular is garnet. Garnet is a natural abrasive that is ideal for the final sanding of woods to get a smooth finish. It wears down quickly so is not recommended for rough sanding. Aluminum oxide is a synthetic abrasive that is ideally used for sanding metals and hardwoods. It is durable enough to get through the material and remain usable for a useful amount of time. Silicon carbide is another synthetic abrasive that is stronger than aluminum oxide. This material allows the sanding of plastics on top of metals and woods. There are other types of abrasives however those are the most common options. 

Method

Once you’ve determined the type and grit of sandpaper to use for a project the last thing you need to confirm is how to sand it. You can sand it by hand by just using pieces of sandpaper. This is ideal for smaller projects or just rough sanding. For detailed pieces, sanding sponges can be helpful as they allow you to better contour the sandpaper to the surface. Vibrating palm, orbital, random orbital, and belt sanders are all sanding tools that can be extremely useful when sanding larger pieces. They allow you to cover more ground when sanding. But, for some of these tools you need to keep an eye out for sanding marks to be left behind. These marks can appear if you leave the sander running in the same place. Once you’ve chosen the type of sander you want to use for a project, you’re ready to go! 

When sanding a workpiece, you work your way up from lowest grit to highest grit in a stepwise fashion. To get to a 220-grit finish, you’d start with a grit around 60, then move up to 80 or 100, and continue that way to the final grit. When sanding you work with the grain of the wood. This reduces visible scratches and reduces tear-out of the final work piece. 

Here at Oregon Woodworks, we sand our shelves up to 220 grit. This leaves us with a perfectly smooth shelf that is ready to accept stain. Whether it is applied by us or by a customer at home it’s sure to look great! The finish is ideal for showing off the grain of the wood since the shelves will be on display in your home for years to come!