What is Tung Oil — A Beginners Guide to What it is and When to Use It

Learn more about what is tung oil? This natural, non-toxic, versatile wood finish is suitable for creating a waterproof surface on wood. For Woodworkers, DIYers and professionals, tung oil is a great natural wood finish to create a hard, durable, beautiful finish on any type of bare wood. Did you know that natural tung oil can compete with other common natural products like raw linseed oil or even chemical lacquers or varnishes?

You might be surprised to learn that a natural, Eco-friendly, sustainable product performs better than many shellacs and varnishes.

What Is the Best Way to Apply Tung Oil

Tung oil creates a shiny, waterproof, durable finish on bare wood surfaces. You can apply the natural seed oil finish and protect musical instruments, furniture items, parquet floors, and even boat decks. If you are looking for a non-toxic, long-lasting protective finish for your woodworking projects. Then, tung oil is an excellent choice.

If you only know a little about tung oil and want to find out about its benefits, then this article is especially for you. Additionally, if you are starting a woodworking hobby, you might wonder about the pros and cons of using tung oil. Surprisingly, even some seasoned woodworking professionals know little about this.

You will learn all you need to know about tung oil for woodworking. You will also get helpful tips on how to use the oil to protect your wood. Additionally, you will learn about the advantages and disadvantages of using tung oil on wood.

What Is Tung Oil?

Tung oil is an oil obtained from the seed of the nut seed of the tung tree (Vernicia fordii). Also called China wood oil, the oil consists of several fatty acids that penetrate the porous wood surface. Its high levels of oily substances give tung oil high resistance to water. 

How does tung oil protect wood?

Tung oil is classed as drying oil. This means it hardens to form a tough solid film through exposure to air. This process, called polymerization, produces a shiny, transparent surface with a deep sheen.

One of the features tung oil is known for is that you can apply several layers to create a solid, deep exterior finish. 

When applied properly, tung oil penetrates deeply into the wood fiber and becomes part of it. Once cured or dried, it creates a lovely, natural-looking non-oily finish that protects wood from moisture and makes it resistant to stains, scratches, dents, and cracks. This also protects the wood against water, insects, mold, mildew, fungus, rot, and decay.

What Is Tung Oil Made From

Tung oil is produced by extracting oil from the seeds of the tung tree. After harvesting the tree nuts and removing the shells, the seeds are pressed to get the oil out. Some commercial tung oil extraction processes use a solvent to extract the oily substance.  

What Is Tung Oil Used For

Tung oil is used as a protective stain on bare wooden surfaces to provide a waterproof finish. Once cured, the oil provides a beautiful, natural-looking finish, protecting the wood against moisture and stains. In addition, because the oily substance penetrates the wood, it becomes part of it, meaning it won’t peel or flake over time.

Tung oil is transparent, durable, and hard-wearing. This makes tung oil ideal for protecting wood and bringing out the grain to enhance its natural beauty. 

Here is a list of the common uses for tung oil in the woodworking industry: 
What is Tung Oil-used on wood cutting board

·        Wooden furniture

·        Wood flooring

·        Boat decking

·        Countertops

·        Wooden chopping boards

·        Musical instruments

·        Wooden toys

The beauty of using tung oil instead of linseed oil or varnishes is that it’s non-toxic. Additionally, you can apply tung oil to all types of wood, and its hardened finish is non-oily yet looks sleek. 

In addition to creating a nice finish on wooden surfaces and being the best choice for wood floor protection, tung oil is also suitable for applying to weathered wood, unfinished wood, concrete, stone, and other similar surfaces. 

What Does Tung Oil Do to Wood

Tung oil penetrates wood surfaces to create a waterproof layer. This effect also enhances the natural beauty of wood, giving it a protective sheen. Tung oil has an amber tint and will give bare wood an attractive honey color. However, you can buy darker shades of tung oil to darken wood pieces.

What Is the Best Way to Apply Tung Oil

Using tung oil to protect wooden surfaces requires applying several coats. The best way to get fantastic results is to apply a thin layer, allow it to dry for a few days, and then apply the next layer. You can use a soft, lint-free brush or foam roller to apply tung oil. 

Here are the necessary steps to apply tung oil to sanded, unfinished wood: 

·        Clean the surfaces: First, sand the bare wooden surface or remove any pre-existing coating or finish. Next, use trisodium phosphate to remove all dirt and grime from the surface and wipe with a damp, clean cloth to remove all dirt.

·        Thin the tung oil before starting: Thin the oil with mineral spirit to make application easier, speed up dry times and enhance penetration. Dilute with mineral spirits as a 1:1 ratio. 

·        Apply the first coat: Use a sponge brush, lint-free cloth, or bristle brush to apply the first layer. The goal is to apply a generous layer to allow the oil to absorb into the wood.

·        Apply subsequent coats to create a hard surface: You will need to wait several days to allow the tung oil to harden. Then, lightly sand the surface and remove the dust each time you apply a new layer of oil. 

·        Wipe off unabsorbed oil: After several coats of tung oil, the wood won’t absorb anymore. At this point, wipe the surface clean to remove excess oil. 

·        Allow the tung oil time to cure: The protected surface will take ten to 30 days to cure fully. During the curing process, keep the item out of direct sunlight. And if you apply tung oil to wooden floorboards, you should wait ten days before walking on the floor with clean shoes.

But you may wonder how many coats of tung oil you should apply. Typically, you must apply around five or more coats of tung oil to create a hard-wearing, durable finish. Of course, this makes applying tung oil a time-consuming process. However, most carpenters agree that the results are worth it. 

After applying tung oil, it takes between two and seven days to dry between coats. You can tell if a surface finished with tung oil is ready for sanding by using 400-grit sandpaper to sand the surface lightly. You are ready to apply another coat if the dust is fine and white.

What is Tung Oil – Pros and Cons

Tung oil penetrates the wood, enhancing its grain and appearance. The honey tones of tung oil also give the wood a rich, warm appearance. And as long as the surface integrity of the wood remains intact, tung oil gives a relatively hard surface with complete water resistance. 

But what are the advantages and disadvantages of using tung oil for your woodworking projects? Here are a few considerations. 

Tung oil pros

·        Tung oil is waterproof: The biggest advantage of tung oil is that it makes wood surfaces water-resistant. The oil absorbs into the wood and, after five to seven coats, becomes 100 percent waterproof.

·        Tung oil doesn’t contain volatile organic compounds (VOCs): Because it’s completely natural, it doesn’t contain potentially harmful chemicals. Therefore, you can safely use tung oil in enclosed environments. 

·        Tung oil is non-toxic: You can safely use tung oil to protect kitchen utensils because it’s food safe. Therefore, use it on fruit bowls, chopping boards, butcher blocks, baskets, and wooden cutlery. Additionally, it’s safe to use on children’s toys and furniture. 

·        Tung oil is easy to apply: You apply tung oil similar to wood stain, paint, or varnish. Because it is natural, you can clean tung oil with a brush using warm, soapy water. 

·        Tung oil has an attractive golden hue: Once applied correctly, tung oil creates a transparent, glossy finish on wooden surfaces and enhances the natural grain. 

·        Tung oil retains its color and doesn’t turn yellow: Unlike linseed oil which becomes discolored, tung oil doesn’t lose its warm amber tones.

·        Tung oil is highly resistant: A significant advantage of tung oil is that it resists vegetable and fruit acids, acetone, and alcohol. As a result, if you spill these kinds of corrosive liquids, you can easily clean the spill using a clean cloth. 

·        Tung oil finishes don’t crack: Because tung oil becomes part of the wood and not just a surface layer, tung oil won’t crack. Instead, it retains its elasticity and flexibility. 

Tung oil cons

·        Tung oil takes time to apply: Using tung oil on wooden surfaces takes a long time to achieve results due to the long drying process. You typically need at least six coats with a few days of drying time in between. 

·        Not everyone likes the smell of tung oil: Many joiners and cabinet makers say that tung oil has an unpleasant odor. This odor is noticeable during curing time and can also linger for a time after. 

·        Tung oil takes time to cure completely: The most significant disadvantage of tung is its long curing process. Apart from taking several weeks to apply layers of oil, it can take up to 30 days for the oil to cure. 

·        Tung oil is relatively expensive: Compared to other finishing oils like linseed, tung oil is relatively expensive. Sometimes, it can cost one-quarter more than varnish, linseed oil, and some paints. 

How Long Does Tung Oil Take to Dry

Pure tung oil takes between 24 and 72 hours to dry. However, actual dry times depend on various factors. For example, air temperature, humidity, ventilation, the thickness of the coat, and the type of wood you are treating affect how long tung oil takes to dry completely.

However, a modified tung oil product may take as little as 30 to 60 minutes to dry. 

Raw tung oil dries faster in warm, relatively dry air. Also, you can speed up drying and absorption time by diluting equal parts of tung oil with mineral spirits. In addition, when working with tung oil, ensure good ventilation. This boosts dry times and gets rid of the unpleasant smell. 

What is Tung Oil — In Conclusion

Tung oil is a versatile drying oil extracted from the seeds of tung trees. This natural wood finish protects your bare wooden surfaces from moisture, stains, and scratches. A tung oil finish on wooden surfaces looks beautiful and glossy and retains its appearance for several years.

However, it’s good to remember that using real tung oil takes time to achieve the best results. Therefore, you should consider this factor when deciding to use tung oil for your next project.