Coming from the seed of the Tung tree, this oil is originally made in China.
The main composition is the fatty acid which creates the hardening epoxy resin. Hence it is popularly used as a wood finish.
It makes the wood water-resistant and creates a satin finish with light golden and no darkening process. The process of how to apply Tung oil is easy and usually includes 2-3 layers.
As it penetrates well to the grain, the oil is used for many woodwork pieces such as furniture, flooring, cabinetry, countertops, wood toys, musical instruments, bamboo, and others.
Tung oil is often used to finish projects for more than one reason. The most common reasons are that the oil is flexible, lasts a long time, is safe for food, and gives a waterproof finish that protects the wood.
Besides, it can also be applied to other materials like brick, metal, stone, and concrete.
Advantages and disadvantages of Tung oil
Advantages of Tung oil:
- It gives attractive color.
- It does not yellow nor darkens over time.
- It is natural, food-safe, and non-toxic.
- It resists water, acids, alcohols, and other fluids.
- It creates more elasticity on the finish compared to other oil finishes.
- The steps of how to apply Tung oil are easy.
Disadvantages of Tung oil:
- It spreads an unpleasant odor.
- It takes a longer processing time due to its slow penetration.
- It is pricey.
- It is only for one-single use as the oil is difficult to store.
- Rough wood grains will stay the same because the oil cannot smooth them.
Things to prepare before applying Tung oil
The wood surface is the first and most important thing to get ready.
Depending on the current condition of the wood, wiping is the last thing to do. If there is any existing finish, sanding is also required to absorb the oil into the grain.
Depending on the used finish type, the current finish must be removed using alcohol or a sanding process.
Also, get rid of any sticking-up grains as the oil will not smooth the surface. Then the essential in preparing is wiping and cleaning any grime or dirt left on the surface.
The hack is by using tri-sodium phosphate ins instead of water. Let it dry and prepare the thinned Tung oil.
Thinning Tung oil
Before getting into the techniques of how to apply Tung oil, preparing the oil with the right viscosity is essential.
Being naturally thick and sticky, Tung oil should be mixed with a solvent. People commonly use a 1:1 ratio for the primary coat and get less oil for the next coats.
This could give a matte look and highlight the deepest color of the wood.
Common thinners for the oil are the traditional oil-based spirits of turpentine, paint thinner, mineral spirits, naphtha, or the new ‘greener’ citrus-based solvent. Each solvent affects the drying process differently.
For a surface with 400 square feet, 500 gallons of pre-thinned or 2 gallons of oil and solvent each is enough. They could do up to 5 coats.
Steps on how to apply Tung oil
Besides the preparation, techniques in applying the oil include:
- When the surface is clean, and the Tung oil mixture is ready, use a clean and dry foam brush, natural bristle, or rag to apply the mixture to the surface as the first coat.
- Let the pores absorb the oil for approximately 40 minutes.
- Repeat the current steps for the second, third, and other coats. Once the surface has been saturated fully, the wood cannot absorb any oil. This is the time to stop applying another coat.
- Wait for another 40 minutes after the last coat.
- Clean the excess oil puddled using a clean and soft cloth.
- Finally, let it cure for 30 days before using the wood. The surface width, temperature, and humidity affect the curing process. Hence regular checking is needed.
Tips on how to apply Tung oil
- Know the type of Tung oil that you use. Several oil products are Pure Tung Oil, Tung Oil Finishes, and polymerized Tung oil.
- Non-pure ones contain mostly petroleum additives or are hydrolyzed, making the coat dry faster. Yet those products are not food safe.
- While applying the oil, rub or brush following the wood grain direction. It brings out natural patterns.
- Prepare a drop cloth, newspaper, or tarp to protect your surroundings from the oil splash. As the oil penetrates any pore it can go, it could leave permanent stains on any surface it falls.
- Do not apply the oil with thinner for kitchenware or any wood pieces related to food as most thinners are toxic for humans.
How to apply Tung oil to kitchenware
Wooden kitchenware includes butcher blocks, spoons, bowls, spatula, tongs, and others. Applying Tung is a safe option to make them last longer and give the best look.
- Use pure Tung oil or mix it with natural solvents like citrus solvent.
- Sand up to 200 grit for a smooth and even surface.
- Clean the debris and dust.
- Soak a clean rug to the mixture and apply it to the surface.
- Wait 40 minutes until the oil gets absorbed.
- Reapply the oil a third time for the minimum.
- When the wood is already soaked, wipe away the excess oil oozing out the wood.
- Let it cure for a month before using the wood as the kitchenware.
When to apply tung oil
Tung oil gets into the wood’s grain, giving it a wet look that makes the grain of the wood stand out.
Because of this, the wood’s color gets slightly darker, giving it a rich, warm color that looks great.
Tung oil gives a fairly hard surface finish that is waterproof and resistant to dust, alcohol, acetone, and different acids like fruit and vegetable acids as long as the surface is still in good shape.
Tung oil has been used outside for years, both above and below the ground. Even though the dried oil is pretty hard, it doesn’t make the best finish.
Most people choose tung oil for how it looks rather than how well it works.
In its pure form, tung oil is a safe finish to use on surfaces that will come in contact with food.
This includes cutting boards, salad bowls, salt and pepper mills, and any other project you can think of.
Repairing, cleaning, and removing Tung oil finish
Clean and remove the oil on the damaged area. Wipe the cleaned area using a soft cloth dipped in the undiluted pure Tung oil.
Then wait for a half-hour. If the area absorbs quickly, redo the step for few times.
For the final layer, wipe the oil mixed with elbow grease and remove the excess.
Not only is it important to know how to use Tung oil, but also how to keep the look. It might help to put the oil on once or twice a year.
To get the oil off the surface, you can use mineral spirits like turpentine, xylene, or naphtha. Rub those liquids directly or using a cloth, then scrape the oil layer.
It’s easy to fix things that were finished with tung oil. Rub the tung oil into the broken area, let it sit for a while, and then wipe off any extra.
But, once more, for the best protection, put three coats of full-strength tung oil on the damaged area.
Myths about Tung oil
- Tung oil is bad for nut allergy: No, Tung nuts belong to drupes like plums, cherries, and peaches, which are good for those who suffer from a nut allergy.
- Applying Tung oil is difficult, and the oil won’t dry: the steps are simple, and the oil takes longer to dry.
- BLO is the cheaper and better version of Tung oil: many prove that Tung oil results last longer and better than the BLO one.
Final Thoughts
Pure Tung Oil needs to be cleaned and taken care of regularly.
Apply at least once a year or more if necessary; it depends on how regularly you use it and how exposed it is to the elements.
It’s important to put enough coats of oil on exposed wood outside to protect it at first.
Oil finishes make the wood’s natural colors stand out. When the surface is wet, you can tell what color it will be.
Always check the color, how well it works with other things, and the result on a surface or an area that won’t be seen.