How to Finish Wood

Preparing the Wood

Sand down the wood. Wood will have flaws like scratches and dents. Whether marks have come from the machines at the mills, or it has become scratched or gouged during handling, or from wear and tear. Before applying any stain, finishing, or paint, you need to sand down the wood to allow you apply to new materials and prevent the flaws from being highlighted. If the flaws in the wood aren't sanded away, the finish that is applied will only highlight and expose any marks or scratches. Start with sandpaper that has a grit of about 120. In most cases, this will remove any of the flaws without causing worse problems. Always sand with the grain of the wood. Don’t sand against the grain.

Repeat the sanding process with a progressively finer grain. You want to sand down the wood until you've reached anywhere between 180 and 220-grit. Repeated rounds of sanding will remove the coarse-grit scratches from the previous passes.

Inspect the wood to determine whether or not you're satisfied with the surface. You can use a high-intensity light, or wet the wood with paint thinner to magnify any remaining blemishes. If you see blemishes you may need to sand the wood again. However, too much sanding in an area that has a blemish may only make it worse. Be careful to try and get as smooth of a surface as possible. Some areas may just have quirks that can't be completely removed.

Wipe down your wood and remove any dust. After you've sanded the wood go over it with a rag to wipe it down and remove any excess material. While you can use any cloth to do this, a tack cloth will pick up the most dust. If you don't wipe down the wood before you apply your stain, you can cause uneven parts and blemishes.

Staining the Wood

Test the color before proceeding with a stain. Apply a small bit of stain to an innocuous part of the wood, such as the underside, or on an extra piece of the same wood. If you are satisfied with the color of the stain you can begin staining the wood. Leaving excess stains on the wood won’t affect the color very much, but can leave blotches and an uneven surface. When preparing the stain, always stir the can, never shake it.

Apply the stain using a rag or a brush. Apply the stain evenly making sure you don’t leave puddles or uneven clumps. Brushes work better than rags and will help you apply the stain more evenly. When you dip the rag or brush in the stain make sure not to let it drip anywhere you don’t want it to go. Blend the stain into the wood thoroughly and make sure you are applying it evenly. Go over your brush strokes several times to spread the stain out and create a smooth area.

Start by applying the stain in a small area, like a leg or a drawer front, so you can get familiar with the drying time. If a stain dries too quickly, it can be re-liquefied by applying more stain, but this will make the stain darker. Wipe off the excess stain right away. Once you know how long it will take the stain to dry you can begin staining the rest of the piece. If the stain isn’t dark enough, you may want to apply several coats.

Continue applying the stain, brushing on a wet coat and then wiping away the excess before it dries. Wait until the first coat has dried completely before adding another coat. Always complete one surface at a time. Don't double up the application of your stain on any areas that have been completed because this will cause a color change.

Finishing the Wood

Pick a finish for your wood. Water-based finishes are less harmful, non-flammable, and more environmentally friendly than other types of finishes. A clear polyurethane finish will give your wood a nice protected coat. Choose a clear finish that has a level of gloss you want for your wood. If you get a glossy finish, your wood will have more of a sheen or glow than a finish with less gloss. Water-heavy finishes will sometimes swell wood fibers unevenly. Apply these finishes lightly, using several coats. You can also carefully sand off any bristles that appear after the first finish coat. Apply at least two more coats for a thorough, even finish over the first coat, which might be more heavily sanded than usual for a finish coat.

Apply a finish to protect the wood from water damage, dirt, or stains. Just like you did with the stain, use a natural bristle brush to apply the stain, going with the grain of the wood, not against it. Stir the stain in the can before applying it. Don’t shake the can. Shaking can create air bubbles which will get transferred to your wood. Water-based polyurethane is the best finish for bare wood, as it highlights the features of the wood itself, such as the grain and the natural color. Oil-based polyurethane will increase durability more in combination with a stain. Wiping varnish (oil-based polyurethane thinned 50% with paint thinner) is the best application for stained, decorative pieces. It is easy to apply flawlessly, but will not help a piece withstand wear and tear.

Paint the finish onto your wood using a natural bristle brush. You can also use a foam brush that is about 2 inches (5.08 cm) wide. Allow the first coat to cure overnight. You will want to apply several coats of finish to your wood. But allow the first coat to completely dry so that you can lightly sand it down and smooth it out before adding more coats.

Sand the finish down once it has dried. Sand the first coat using 280-grit sandpaper, or a finer sandpaper if you don’t need to do much evening out. Remove the dust with a tack rag or a vacuum and then apply the second coat.

Apply the second coat just like paint. When there are bubbles, remove the bubbles by brushing back over the area to smooth it down. When possible, move with the grain of the wood. On flat surfaces, brush side to side, and front to back. Apply the finish as thinly as possible, and line the brush strokes up in rows so that the finish covers the wood evenly.

Sand each subsequent coat. Just as you did with the first coat, you want to lightly sand each subsequent coat once it's cured to remove any dust nibs. Again, remove any dust with a tack rag or vacuum.

Repeat the application process two or three times. Once you have a few layers of finish down you can add your final coat of finish. Do not sand the last coat. You don’t have to sand down the final coat as sanding will remove the nice shine and finished look. Once it’s dry wipe it down with a soft rag to remove any particles.