A durable finish for woodworking pieces, furniture, and flooring, varnish beautifies wood and protects it from scratches and stains. To the uninitiated, achieving a smooth and lustrous look may seem like a magician’s trick, but once you understand the basics, varnishing wood couldn’t be much easier.
Make sure the surface you wish to varnish has been sanded smooth, and don’t begin varnishing until you have cleaned your work space. Varnish dries slowly and rarely fails to attract dust, hairs, and loose debris, so the success of your project ultimately depends, in part, on how well or poorly you clean up beforehand.
What to Look for in Wood Varnish
Before we dive into our top wood varnish picks, let’s go over a few factors you should consider before shopping. Keeping these factors in mind will ensure that the varnish you choose falls in line with your needs, preferences, and intended use.
Type
When choosing a varnish, it is necessary to study information about its composition, properties, and safety measures during operation.
It is also necessary to observe the staining technology according to the manufacturer’s instructions. Only in this case, you can get a high-quality varnished coating.
In the modern market there are many different types of varnishes made on different bases. The most common type of varnish are:
alkyd varnish;
nitro-varnishes (nitrocellulose);
bituminous varnish;
oil varnish;
polyurethane varnish;
acrylic varnish;
epoxy varnish.
There are also narrowly targeted materials that are used exclusively for certain purposes, for example, ship, parquet, impregnating, etc. Consider the properties of different paintwork materials.
Acrylic
This may be the most eco-friendly option. Its water-based design ensures a toxin-free varnishing experience and produces far less odor than oil-based varnishes. Acrylic varnish is also known for its versatility—not only can you use it for indoor and outdoor projects, but you can also use it on certain non-wood materials. That said, this type of varnish is normally used to protect acrylic paintings on wood, and this is the best application for it. Depending on your preferences, acrylic may give you the most for your money in terms of safety and quality.
Exterior
Exterior varnishes are designed for use outdoors and can stand up to the elements. They typically feature strong UV-resistance as well as resistance to fungal growth. If you want to ensure your outdoor wood creation lives a long, mold-free life, exterior wood varnish will be your best option.
Interior
Interior varnishes are best suited for indoor use. They don’t possess UV-resistant or waterproofing properties, but they can protect wood against scratches and abrasion. Popular applications of interior varnish include furniture and kitchen countertops.
Polyurethane
Polyurethane varnishes are the preferred option for wood floors. The harder surface they create tends to provide great overall protection from the effects of heavy use. On the downside, they are not UV-resistant—for this reason, polyurethane is better for indoor use.
Yacht (Marine Spar)
This variety of varnish is for use on yachts and boats. It’s specially designed to protect the wood from water exposure and a variety of weather elements. Today, yacht varnishes also include UV-resistant components, making them excellent for use outdoors. In fact, marine spar varnishes are highly popular for use as general outdoor varnishes.
Application Tips for Types of Wood Finishes
Consider these tips when selecting and applying different wood finishes.
When choosing a wood finish, apply a small amount to a piece of wood that matches your flooring or furniture to make sure it has the coating what you want.
Stir the finish in the container before application.
Apply the finish in thin coats.
Use a synthetic or natural bristle brush or an application pad to apply the finish according to manufacturer’s directions.
Allow the first coat to dry completely before applying any additional coats.
Lightly sand between coats to remove drips and bumps, then wipe thoroughly.
After the final coat has dried, wipe down the entire surface to remove any remaining particles.
The different types of wood finishes provide varying levels of protection to your wooden furniture and flooring while enhancing the wood’s appearance. If you need to protect the surface, the best clear coat for wood may be polyurethane.
How to Varnish Wood
Varnishing wood is an easy way to both protect the wood inside your home, whether it is stairs, railings, cabinets or more – as well as give it a beautiful shine to enhance the allure of your space. Check out this article on how to varnish wood for more info.
Step 1: Prepare the varnish for the initial coat, if necessary.
Some varnishes, such as those that come in a spray can, do not need any preparation; other types of varnishes should be thinned for the first coat. This helps seal the wood and prepare it for the proceeding coats. The rest of the coats do not to be thinned.
- If you are using an oil-based varnish, thin it with a paint thinner, such as turpentine. Use one part varnish to one part thinner.
- If you are using a water-based or acrylic-based varnish, thin it with water instead. Use one part varnish to one part water.
Step 2: Apply the first coat of thinned varnish and let it dry.
Use a flat paintbrush or foam applicator to apply the varnish to the wood. Use long, even strokes, and work along the wood grain. Let this first coat dry for 24 hours.
If you are using a spray on varnish, hold the can 6 to 8 inches away from the surface and spray on a light, even coat. Let it dry according to the manufacturer’s recommendations.
Step 3: Sand the first coat and wipe it with a damp cloth.
After you have applied the initial coat of thinned varnish, you will need to smooth it out. You can do this by buffing the surface of the varnished wood with 280-grit sandpaper,[6] and then using a dry cloth to wipe away any dust of debris.
- Make sure that you wipe down your work space with a damp cloth to get rid of any dust caused by the sanding.
- Make sure that you clean your brush with paint thinner (if you are using an oil-based varnish) or water (if you are using a water-based varnish).
Step 4: Apply the next coat of varnish and allow it to dry.
Using a clean brush or a new foam applicator, apply the varnish to the wooden piece. Once again, make sure that you are brushing along the wood grain. You do not have to thin this layer. Wait 24 hours for this layer to dry.
If you are using a spray on varnish, you can spray on another coat. Make sure to keep the can 6 to 8 inches away from the surface, and spray on a single, light coat. If you spray the varnish on too thickly, you may end up with puddles, drips, and runs.
Step 5: Sand the second coat and wipe it clean with damp cloth.
Once the second coat of varnish has dried, sand it gently with a fine-grit sandpaper, such as 320-grit.[7] Let the varnish dry 24 hours before applying the next coat, and remember to clean your work space of any dust or dirt caused by the sanding.
Step 6: Continue applying more varnish and sanding between coats.
Apply 2 to 3 more coats of varnish. Remember to let the varnish dry between coats, and to sand and wipe the varnish clean before applying more varnish. Always work along the grain when applying and sanding the varnish. When you get to the last coat, do not sand it.
- You can continue working with 320-grit sandpaper, or move up to 400-grit.
- For optimal results, consider waiting 48 hours before applying the final coat.
Step 7: Wait for the varnish to finish curing.
Varnish will typically need some time to finish curing. To prevent ruining the varnish, leave your wooden piece some place where it will not be disturbed. Some varnishes finish curing with 24 or 48 hours, while others need as much as 5 or 7 days. Some varnishes require 30 days to finish curing. Refer to the instructions on the can for more specific drying and curing times.
Supplies for Varnishing
Tools for Applying Varnish
Most one- and two-part varnishes can be applied using a brush, a foam roller and brush (roll & tip method), or some type of sprayer (airless, HVLP, etc.). There’s even varnish that comes in an aerosol can! Setting up and adjusting spray equipment takes time, as does cleaning the equipment. But you don’t need professional spray equipment to get professional results.
A good, natural bristle brush yields excellent results. We recommend getting the best quality brush you can afford, using it just for varnishing, cleaning it properly, and it’ll last for years to help you maintain your beautifully varnished finishes. On large areas, consider the roll & tip method: Use a high-density, lint-free foam roller to apply the varnish, and have someone follow behind you with a wide-bristle brush to even out the finish, removing any small bubbles introduced by the roller.
What Type of Varnish Brush Should I Use?
Using the right brush is one of the most important ways to get a smooth, beautiful finish. The other is having the right technique. But all the technique in the world won’t help if you don’t have the right brush. Try painting your house with a push broom. You’ll get paint on the surface, but it won’t look good. The same holds true for applying finish coats of varnish with a foam brush, because even though foam brushes don’t leave brush marks, they tend to introduce more bubbles. Small bubbles can be sanded out of build coats, but not finish coats.
To keep costs down, it’s okay to use a foam brush for the sealer and build coats, but a soft-bristled badger hair brush is the best brush for finish coats because it lays the varnish down smoothly with no bubbles or brush marks. Badger hair brushes are also best for removing air bubbles when you’re rolling and tipping.
Other Equipment Needed for Varnishing
Heat gun or chemical stripper for removing old varnish. Our TotalBoat TotalStrip paint and varnish remover is easy to apply, odor-free, biodegradable, can strip up to 25 layers in a single application, requires no acid wash neutralization, and cleans up easily with just plain water.
Sanding blocks – Choose from a variety of commercially available hard and soft sanding blocks for different purposes when sanding by hand. For example, a soft sanding block aids in sanding curves and contours; a hard sanding block is best for sanding straight surfaces.
Scrapers for removing old varnish. Pull scrapers offer the best results with the least amount of effort and gouge potential.
Masking tape – use a high-quality masking tape that removes cleanly to protect non-varnished surfaces. For taping curved surfaces, use a flexible tape that’s durable enough to snap a really nice line.
Clean, lint-free wiping rags and denatured alcohol for cleaning wood surfaces and removing any dirt and oils.
Tack cloth – tacky cloth for wiping down the wood before applying varnish. Removes any lingering dust.
Synthetic mesh strainers for filtering contaminants when pouring varnish from the can into your paint pot.
Optional items – Random-orbit sander to expedite sanding large areas, and a vacuum cleaner to help remove any sanding residue before wiping down with a tack cloth.
Conclusion
Varnishing wood for furniture, walls, and flooring takes time. Some may settle for a single coat while wood used for heavy-duty activities and those installed on high traffic areas should be stained three or more times. Every coat is dried and sanded before another one is applied. Only this way will varnish penetrate deep into the wood and protect it.