Floor sanding can be done in a variety of ways, and in the past was done by hand. Hand sanding a floor is both tedious and can be damaging to your knees and back.
Todays modern handyman will typically use an electric sanding machine which is readily available for purchase in most home centers like Home Depot or Lowes, or for rent at a local rental store.
Hand held or small appliance sanders still use standard sheet sandpaper, and are used in the hard-to-reach places like corners, and in other areas that require a more detailed finish.
Types of Sanding Machines
Sanding machines are available in two varieties, drum and disk. Each is effective at sanding the wood floor and each has its own pros and cons. The drum sander has to be used back and forth with the grain of the wood.
It is effective at sanding but is unable to reach the last couple of inches of floor near the edge and requires a hand held edger or palm sander to reach the last bits or you may use sandpaper and finish by hand or with a small hand held device like a Lie-Nielsen Toolworks scraper.
The disk sander gets much closer but goes in a circular motion across the grain and care must be taken to use fine grit sandpaper to ensure a smooth finish and that swirls are not visible in the finish. The small hand sander is necessary to complete the edges here as well.
Sandpaper Grit Grades
Sandpaper removes the surface of the wood or finish in coarse to fine increments depending upon the grit size of the paper. Coarse grit removes more wood and finish with each pass, but fine grit does a smoother job that lessens the ability to see the scratches.
Coarse sandpaper is often used when the wood and/or finish requires a deeper level of removal, and the fine sandpaper acts as a finishing treatment. For floor sanding, coarse sandpaper is used to remove the bulk of the old finish, roughness, or imperfections in the wood and to level uneven spots.
The fine sandpaper will then clean up the coarse fibers and leave the wood smooth and ready to be finished. Hardwood like oak will resolve to a mirror-like finish easily, while softer woods like pine require very fine sandpaper to achieve that result.
Before beginning the sanding procedure, sweep all dirt, dust, and debris from the surface of the floor. If the floor is excessively dirty, use a shop vacuum to go over the floor to remove the remainder.
Use a nail set or punch to tap any nails that stick up above the surface of the floor to avoid damage to the equipment, or yourself. Remove the baseboards to avoid damaging the molding and run the electric sander over the floor.
If youre using a drum sander, youll want to follow the grain of the wood and in controlled circular motions if using a disk. The first or second pass over the floor should be done with coarse paper, and the third with a finer grit to smooth the finish.
Afterward, you can polish the wood with steel wool as long as it is not unprotected oak. The fibers from the steel wool can leave metal shards in the wood can potentially leave iron stains in certain conditions.
One way to get around the rusting issue is to use bronze wool rather than steel.
If the boards run parallel, always sand in the direction of the planks to ensure that the finish is with the grain. If the floor is uneven, sand with course paper at a 45 degree angle to eliminate any peaks or valleys in the wood surface.
The final pass should be made with fine sandpaper to return the wood to a smooth surface. An edger should be used after each time that you sand the surface with the machine to ensure that the edges are at the same level and degree of smooth as the floor.
Inspect the floor for any blemishes and scratches after the bulk sanding is complete and use very fine sandpaper to smooth any scratches noticed. Once the sanding is complete, sweep the floor thoroughly and if need be, run the vacuum again to get up all the grit remaining.
You should be able to get down and look across the floor and see most of the imperfections that may remain. You can easily get these with fine grit sandpaper to smooth out the finish.