Varnish is a very popular treatment to protect and preserve wood. Varnish is a resin that is dissolved in a liquid. This resin is then applied onto various surfaces such as wood and metal to create a hard, clear, and shiny surface when it is properly dried. Varnish is a popular choice for treating wood.
Most furniture pieces you buy in the store have been treated with a coat of this valuable product. Treating your wood furniture or floors with a layer of varnish offers many great benefits.
What Are The Benefits Of Varnishing Wood?
The main purpose of varnishing wood is to protect the wood so it will last many years. But varnish also offers plenty of other advantages. Here is a quick look at some of the best benefits of varnishing wood surfaces:
Enhances The Natural Beauty Of Wood
When you place wood in water, the natural colors come to life and wood looks more vivid and beautiful. Wood cannot be kept wet or it will start to rot. But varnishing it has the same effect on it as water. This resin brings out the vibrancy and bright colors of natural wood and makes these pieces look more radiant and beautiful.
Binds The Surface
When you scratch wood surfaces, the natural fibers in the wood are exposed. Over time, wood can become brittle and those fiber pieces will start to come loose. Varnish acts as a glue to stick these microscopic pieces in your wood together. It binds the surface to keep your wood from perishing or cracking.
Prevents Damage To Wood
Varnish is a very hard resin. This resin acts as a protective layer to protect your beautiful wood surface from external damage. All scratches, bumps, and knocks on your furniture will be on the varnish itself and not on your delicate piece of furniture.
Prevents Moisture Transfer
Wood naturally has a little bit of moisture inside it. The atmosphere also has a lot of moisture. When wood loses too much moisture and natural oil, it can become brittle. When wood absorbs too much moisture from the air, it can start to rot. Varnish acts as a shield that prevents moisture and oils from leaving your wood and this layer also keeps your wood from absorbing moisture from the atmosphere. As a result, your wood is preserved for longer.
How to Varnish Wood
Now that you understand the importance of treating your wood with this durable finish, it is time to learn how to varnish wood. Here is a quick look at the main materials you will need before you can get started.
Materials Needed:
- Wood varnish
- Thinners or water (depending on the type of varnish you have)
- Sanding paper
- Paint stripper (if the wood was previously painted)
- Small paintbrush
- Larger paintbrush
Tips for Choosing the Right Varnish
Before you go shopping for a varnish, you should know that there are quite a few different types available on the market. Some varnishes are designed for protecting musical instruments; others are manufactured to protect oil and acrylic paintings. Here is a quick look at the most common varnish types you can find in your local hardware store:
Oil-Based Varnishes
These varnishes are incredibly durable. They are mixed with paint thinners and usually have quite a strong smell. Any brushes or cleaning you need to do after using this varnish needs to be cleaned using thinners or these tools will be completely ruined.
Acrylic and Water-Based Varnishes
These varnishes don’t have such a strong odor, and they dry much faster. They are not as durable as oil-based varnishes, but the cleanup is much easier since you can wash brushes and other painting equipment in soap and water.
Spray-on Varnishes
These varnishes are very easy to use since you don’t need any brushes, and the spray on varnishes doesn’t need to be thinned. Spray varnishes do have a strong smell that can make you feel light-headed. To use these, you can simply prepare your surface and spray a smooth coat over your wood surface.
Varnish Colors
Varnish can be completely clear in color. These varnishes won’t alter the color of your wood at all. But some varnishes are tinted. A tinted varnish can change the color of your wood. Varnish comes in a variety of tints that can vary from reddish to almost black.
How to Prepare Your Surfaces
Wood surfaces need to be prepared correctly before you can treat these surfaces with varnish.
The techniques you need for prepping your surface depend on the condition of the wood. Here is a quick look at the best ways to get your surfaces ready for varnishing.
New Wood
New or untreated wood is the easiest to prepare because you don’t need to remove any previous sealants from the wood. Here is a quick look at the steps required to prepare new wood.
- You should first remove all dust and dirt from the wood so you can get a proper look at the condition of the wood.
- If there are holes in the wood, these will need to be filled with wood putty before you proceed.
- Once the wood putty is dried, you can grab a piece of fine-grit sanding paper and smooth the surfaces.
- Once all surfaces are properly smoothed, you should clean off all dust by wiping down your wood using a wet cloth.
- When your wood is completely dry, it will be ready for varnishing.
Old Wood
Old wood surfaces can be tricky to treat because it could have absorbed some oils, grease, or dirt over the years. Here is a quick look at the best ways to prepare old wood.
- Clean off all grease or dirt using a cloth dipped in turpentine oil. You can also use wet sandpaper to remove these elements from your wood.
- Grab your fine-grit sanding paper and sand down any surfaces that have become coarse or brittle.
- Keep sanding until your surfaces are smooth. It is best to use 180 to 220-grit sandpaper and sand with the wood grain direction.
- Remove all dust from your wood by using a damp cloth.
- When the wood is completely dry, it will be ready for varnishing.
Wood with Old Varnish
A fresh coat of varnish can make your old furniture look much better. To prepare a wood surface that was once treated with varnish, you can follow the following steps.
- Wipe down the entire surface with a wet cloth, so you can see the exact condition of the varnish.
- If the old surface is peeling or cracked, you might need to remove all of the old varnishes. To do this, you can try to use thinners to strip the old varnish off. Many do however find it much easier to sand the layer of varnish off using an electric sander.
- If your varnish is still in good condition, you should check it for grease and dirt. Grab a cloth with turpentine oil and remove all grease and dirt from the surface. You can lightly sand problematic areas in your old varnish.
- You should now remove all dust and dirt from the surfaces. To do this you can wipe the furniture piece down using a moist cloth.
Wood with Old Paint
There are two different ways to prepare wood that was painted. Here is a quick look at the best steps to take.
- If the paint is still in good condition you can simply wipe the paint off, remove grease and dirt and allow it to dry. Varnish can be applied over some paint surfaces and will enhance the vibrancy of your paint.
- If the paint is cracked or if you want to remove the paint surface from the wood, you will need a lot of elbow grease. You can use a paint stripper to remove the paint from your wood surface. This can however be quite tricky because paint becomes sticky and paint strippers can have a very strong smell. Alternatively, you can remove the paint with sanding paper or with an electric sander.
- Once all paint has been removed, you can check your wood for oils or grease. These need to be cleared off using turpentine.
- If your surface is completely smooth, you can remove all dust by wiping the furniture down with a moist cloth.
Applying Your New Wood Varnish
Once your wood surface has been fully prepared, it will be time to apply the fresh coat of varnish. It is very important to ensure that your surface is completely dust free before you get started.
Here is a quick look at the right steps for varnishing wood.
Choose a Proper Work Area
Even if you are using water-based varnish, it is best to work in a well-lit and well-ventilated area. You want to do this because varnish and thinners have a very strong smell that could make you feel lightheaded and nauseous.
Clean Your Work Area
It is also important to clean your work area before you start with your varnish. Your area needs to be dust and dirt free. You might need to mop or vacuum your work area before you get started. If you are working outside then it is best not to varnish on windy days.
Consider the Temperature and Humidity
Ideally, the temperature in your work area should be around 70 – 80 °F (21 – 26°C). If it is too warm, the varnish could dry off too fast and air bubbles can form on your surface. Avoid painting on cold or rainy days because cold temperatures or high humidity levels can make it hard for your varnish to dry which leaves plenty of time for the dust to settle in your surface.
Wear Protective Gear
Varnish does contain lots of chemicals. It is best to wear protective gear so these chemicals won’t make contact with your skin. It is impossible to remove varnish from clothing. Before you get started, you should grab an old set of clothes, protective gloves, and glasses. Some also prefer to wear a dust mask when using varnish with lots of fumes.
Prepare Your Varnish
Once your wood is prepared and you are all geared up, it is time to prepare your varnish. Here is a quick look at the right ways to prepare different varnishes.
Spray Varnishes
You can just give the can a proper shake to mix everything.
Oil-Based Varnishes
Some people prefer to thin these varnishes. To thin, mix one-part varnish to one part thinner. Use a disposable stirring stick and mix it properly. If you prefer not to thin your varnish, you can simply grab your stick and give your varnish a good stir.
Water-Based Varnishes
These varnishes need to be thinned with water. You can use one part varnish, one part water to thin this varnish. Mix it properly before applying it to your surface. Some do however prefer not to thin varnish and it can be applied as-is.
Time to Varnish
You are now ready to varnish your surface. Varnish needs to be applied in layers. Use a flat paintbrush or foam applicator to apply a thin layer of varnish to your wood.
It is best to use long even strokes and to work along with the wood grain. Here is a quick look at the layering process.
Applying the First Layer
Apply the first layer of varnish using your paintbrush. If you are using a spray-on varnish, you should hold the can 6 – 8 inches away from the surface and spray a light even coat. Allow your varnish to sit for 24 hours so it can dry properly.
Remember to clean your brush with thinners.
Once the surface is fully dried, you should smooth it out. Grab 280-grit sanding paper and sand down your surface and wipe it down with a moist cloth.
Applying the Second Coat
With your surface freshly cleaned, you can now apply a second coat of varnish. Remember to stir your varnish again and apply a thin layer. Most people prefer not to thin the thinners for this layer. Clean your brush using thinners or water (depending on the varnish medium). Allow your varnish to dry for 24 hours.
For spray-on varnishes, you can use the same technique as above and allow it to dry.
You should also sand down your surface and wipe it with a damp cloth once the varnish is completely dry.
Apply More Coats
Ideally, you should apply 2 – 3 coats of varnish for a proper seal. Some people do however prefer to apply more than three coats.
Cure the Varnish
When you are finished applying the final layer, you will need to leave the furniture to cure.
Some varnishes can cure in 24 – 48 hours, others will take 5 – 7 days to properly dry. Some varnishes can even take up to 30 days to properly dry.
When all of these steps have been executed properly, your wood surface will be properly treated with varnish, and it will enjoy the best protection for many years to come.