Wood finishing is the final process of any carpentry work; specifically, it involves the application of one of the various protective products available, usually transparent, which are often referred to with the generic name of "finish". Whether you are restoring an old piece of furniture or building a brand new one, you need to infuse it with character and vitality with an impregnator and finish; start by sanding the surfaces, then apply the primer and finally protect the wood with the final product.
Steps
Part 1 of 3: Prepare the Wood
Step 1. Sand the material
The wood is likely to have small imperfections and dents due to the use of machinery and tools; there may be scratches or notches caused by workmanship or wear. Before applying any primer, paint or finish, you must sand the surface to allow the products to adhere and prevent the defects from becoming even more noticeable.
- If you don't sand away the imperfections, the finish will emphasize them by exposing any scratches or marks.
- Start with about 120 grit sandpaper which, in most cases, is able to remove any flaws without making the problem worse.
- Rub the paper along the grain of the wood and not in a perpendicular direction.
Step 2. Repeat the process gradually switching to a finer paper
You should sand down to use 180-220 grit sandpaper.
Repeated sanding cycles eliminate scratches left by coarser paper
Step 3. Inspect the wood to determine if you are satisfied with the result or not
You can use a high-intensity lamp or wet the wood with a thinner that highlights any flaws.
- If you notice any inaccuracies, sand the cabinet again; however, overdoing one area runs the risk of making the damage worse.
- Strive to get the smoothest surface possible; some areas have anomalies that cannot be completely removed.
Step 4. Dust the wood and remove any particles
After sanding is complete, scrub the material with a rag to get rid of any residue. While you can use any fabric, you should rely on an electrostatic cloth to lift most of the dust.
If you neglect this step before applying the primer, you can get uneven areas and imperfections
Part 2 of 3: Apply the Impregnator
Step 1. Check the color before proceeding
Spread a small amount of it on a hidden area of the furniture, for example on the base, or on a scrap piece of the wood itself; if you are satisfied with the shade, you can start applying.
- Leaving an excessive amount of product on the wood does not alter the color much, but it can generate patches and uneven areas.
- When preparing the primer, always mix it in the can and never shake it.
Step 2. Apply the product with a rag or brush
Try to get a uniform result without drops or lumps of product; for this purpose, brushes are more suitable than rags because they guarantee a more homogeneous work.
- When you dip the rag or brush into the primer, avoid dripping it onto surfaces you don't need to treat.
- Make sure the color is well blended and check that the work is uniform; pass the brush several times to spread the primer and create a smooth surface.
Step 3. Start with a small area, such as a leg or the front of the drawer
This way, you become familiar with the drying times. If the product dries too quickly, you need to make it smooth again by applying another coat, but remember that you will get a darker shade; wipe off excess primer immediately.
- Once you understand how long the product takes to dry, you can start spreading it over the rest of the piece of furniture.
- If the color isn't dark enough, you need to brush several coats.
Step 4. Continue applying the product in multiple layers and scrub away the excess before it dries
Wait until one coat is completely dry before applying the next and finish the job on one section at a time.
Do not put any other product on an already treated area, otherwise it will alter the color
Part 3 of 3: Finishing the Wood
Step 1. Choose a finishing product
Water-based ones are less dangerous, are non-flammable and are less harmful to the environment than other types. A clear polyurethane finish provides the wood with a nice protective layer.
- Choose a transparent substance with the level of sheen you want; if you take a glossy finish, the wood is brighter or luster than that treated with a matte product.
- Products with a high water content lead to an uneven expansion of the wood fibers; if so, apply several thin layers.
- You can also gently sand any visible wood fibers after applying the first coat. Apply at least two more coats, in addition to the first, to obtain a uniform and precise result that can be sanded even more before the final layer.
Step 2. Apply the finish to protect the wood from water damage, dirt or stains
Just like you did with the stain, opt for a natural bristle brush and follow the grain direction of the material.
- Mix the finish inside the can before using it; do not shake the container, otherwise bubbles form in the liquid which are then transferred to the cabinet.
- Water-based polyurethane finishes are best used on bare wood, as they highlight the natural characteristics of the material, such as color and grain.
- Those based on oil, in combination with the impregnating agent, enormously increase the resistance of the furniture.
- Furniture lacquer (an oil-based polyurethane finish mixed with an equal dose of paint thinner) is the best choice for decorative pieces treated with the stain; it is a substance that is easy to spread and does not create any defects, but it is not very effective against wear.
Step 3. Apply the finish using a natural bristle brush
You can also opt for a foam applicator about 5 cm wide; wait overnight for the first coat to dry.
You need to apply several layers, but always wait for each to dry so you can sand and smooth before moving on to the next
Step 4. Sand the finish when it is dry
Use 280-grit sandpaper or finer, in case there aren't many imperfections to remove.
Remove dust with an electrostatic rag or vacuum cleaner before brushing the second layer
Step 5. Apply another coat of finish
If you notice bubbles, remove them by running the brush over the area; whenever possible, follow the direction of the wood grain.
- When working on smooth surfaces, move the brush from side to side and from front to back edge.
- Apply the thinnest possible layer and line up the various strokes of the brush to evenly cover the surface.
Step 6. Sand each subsequent layer
Just like you did after the first application, you need to lightly sand the finish after each coat and after it has dried completely to remove any imperfections.
Remember to dust the surface with an electrostatic cloth or vacuum cleaner
Step 7. Repeat the process two or three times
Once you have a few coats of finish, you can move on to the final one that does not need to be sanded.
- You don't have to sand the last coat, otherwise it will make the finish matte.
- Once dry, wipe the furniture with a soft cloth to remove any particles.
Advice
- For best quality results, it is recommended to use a separately packaged finish and primer and not the combined products.
- Apply the primer and topcoat with long, smooth strokes of the brush.
- Remember to remove all traces of dust or particles with an electrostatic cloth before applying new layers of product.
- If you're not using a work table, spread out a house painter's cloth, wear clothes you don't mind ruining, and put on protective gloves. It is practically impossible to remove the product that splashes on surfaces that are not to be treated.
