Beautiful wood grain is a desirable attribute of hardwood floors. To bring back the full potential of the wood, a floor can be sanded, stained and resealed. The proper type of sander depends on the amount of sanding that needs to be done.
Choose the appropriate sander
A drum floor sander is an aggressive machine used to refinish old and distressed floors. Drum sanders use sandpaper belts, usually between 20- and 120-grit with an 8-inch width. Most drum sanders include a dust collection system. For hard-to-reach corners and edges along baseboards, a handheld floor edger is used in conjunction with the drum sander. Random orbit floor sanders are less aggressive and less difficult to use than a drum sander. This machine is best used for light or medium sanding conditions, using quick change hook-and-loop paper designs. A square buff floor sander is an easy-to-use machine that is best for recoating and general floor maintenance. A square buff sander uses high-grain sanding pads, often between 120- and 220-grit.
Begin the sanding process
Once the appropriate sander is chosen for the job, sanding begins with the lowest grit sand paper. In general, begin with 20- or 60-grit when using a drum sander. The purpose is to remove dirt and old stain, creating a new and level surface. A 20-grit sandpaper can be skipped if the floor is relatively smooth. The sander is started while the machine is tilted back, making no contact with the floor. Once the sander is running at full speed, it is slowly lowered to the hardwood. Drum sanders remove a lot of material very quickly, so it is very easy to gouge the wood. It is important that the sander is moving at all times, working slowly in the same direction as the grain of the wood. Edges and corners can be sanded with a handheld floor edger, using the same sandpaper grit and moving in the same direction as the drum sander.
Move to the next grit
Once the first pass is finished with the lowest-grit sandpaper, the drum sander is equipped with sandpaper a step up in grit ? likely 80-grit. The sanding process continues, using the same method as the first pass. Once finished, a third pass is accomplished with the higher 120-grit sandpaper. When using the floor edger, the same grit progression should be used as the drum sander. Once the third pass is finished, it is recommended that the floor either be hand sanded or buffed with a 220-grit sandpaper. This final pass gives the hardwood the smoothest possible finish. After the sanding is complete, the floor should be cleaned using mineral spirits and a clean rag to remove any dirt or debris before the stain or clear coat is applied.