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the wood until it is very smooth. Sand the entire surface with a hand sander or an electric sander to get rid of rough areas and imperfections. If your wood is pretty rough to start with, begin sanding with a rough sandpaper with a grit of 100 or 120. Progress from rougher grit to finer grit sandpapers, which allows you to reduce major irregularities before achieving a fine finish. To get a very smooth surface you should end with 400 grit sandpaper.  Even if your wood already feels pretty smooth, take the time to run 400-grit sandpaper over it before sealing it. This will ensure that the surface is completely smooth once the sealant is applied. Sand with the grain, which means that you need to follow the lines of the wood grain straight back and forth. This will help you avoid leaving behind swirly marks on the surface. Wipe the entire surface several times. This will help you avoid getting wood particles stuck in your sealant, which will create an imperfect surface.  A tac cloth is a special sticky cloth that is specially made to remove the dust from the surface of wood after sanding. Tac cloth will remove even fine particles that resist removal from a cloth. Avoid using water on unsealed wood, because it can alter the wood's grain and create roughness. the wood to change the color or to highlight the grain, if desired. Apply the stain before you apply your sealant so that it is able to soak into the surface. There are a variety of colors and types of stains available but most are applied with rags. First you will wipe your stain on the wood and then let it set for a specific amount of time, which is stated on the stain packaging. Then you will wipe off the excess with a clean, dry rag.  The container of your stain will tell you how long you need to wait after applying stain to apply a sealer. Wood stains are available at all hardware and home improvement stores. These products allow you to apply colorant and create a water-resistant surface at the same time. They are a quick-finish option if you have a large surface and not a lot of time to seal it.  For example, many people use this type of combo product with sealing a deck, due to the large surface area that needs to be treated. They are available at all hardware and home improvement stores. These products can typically be applied with a brush or a roller.
Sand Remove any sawdust from the surface with a dry rag or a tac cloth. Stain Use a stain and sealant combo to complete your project quickly.