How They Work
A drum sander typically consists of a drum that measures 8 inches wide by 20 inches long. It uses a sheet of sand paper that is locked into the bottom of the unit and works by moving the paper on a rotating drum. This provides a cutting action that aggressively sands the floor surface. Orbital floor sanders use a 12- by 18-inch sanding pat that oscillates in an orbiting motion. The orbital motion allows the paper to skim the floor, but without a lot of pressure.
The rotating motion of an orbital sander ensures that no scratching from repetitive motion over one area occurs, making it ideal for anyone new to floor refinishing. It is also beneficial for narrow areas, such as hallways and closets, where a drum sander can’t reach. Drum sanders are used more often than orbital sanders because they do a thorough job at maximum speed. They’re able to remove tough layers of finish that an orbital sander may not. The movement of an orbital sander’s paper is limited, making it less likely to leave marks, but this makes it slow. A drum sander is much faster and can sand a large space in a shorter amount of time.
Orbital sanders tend to be slower than a drum sander, so in a large space they can be inconvenient. Drum sanders, on the other hand, may not reach all areas of a floor if you have odd angles or rounded edges. However, inexperienced floor finishers may have trouble operating a drum sander without damaging the floor. The sander must move constantly and evenly, because stopping while the drum is moving can result in a depression in the floor.
Choosing the Right Sander
A drum sander essentially cuts the finish from the floor, while an orbital sander grinds. With a drum sander, the action is aggressive, with the drum spinning at about 1,800 rpms. If you’re sanding a surface that is significantly damaged, cupped or has a thick layer of finish, a drum sander is the ideal choice. Orbital sanders do not provide enough cutting action to repair these problems. However, if the surface is in good condition and only a light sanding to remove a topcoat or you want to apply a fresh coat of sealant, a drum sander is not necessary. Orbital sanders provide the sanding power necessary for these jobs.