Tung oil is a famous eco-friendly wood furniture finish. It differs from other woodworking coats and protects the wood from multiple environmental elements.
However, the product has drawbacks, requiring the user to be careful during the application process.
So, check out the Pros and Cons of Tung Oil for a better understanding.
Woodworkers love tung oil as it is a food-safe, durable, flexible, and protective waterproof finish.
In addition, the formula dries quicker than other oils, making it less time-consuming and easier to apply.
But tung oil also produces a mildly disagreeable odor after application, has relatively poor penetration, and is difficult to store.
This write-up offers a detailed account of the tung oil’s benefits and downsides and its comparison with linseed oil.
Also, you will get practical tips on how to deliver a professional finish.
Table of Contents
What Is Tung Oil?
Tung oil comes from seed kernels from a Tung tree. You can also call it Lumbang oil, China Wood Oil, or wood oil.
This oil has been in existence for hundreds of years in China. Woodworkers used it to preserve wood ships.
Tung oil soaks into the lumber. Then, it hardens to deliver an impermeable hydrophobic coat.
Moreover, the oil layer penetrates up to 5 mm into the lumber, delivering superior waterproofing.
As a result, the oiled project remains intact regardless of being above or below the ground.
Tung oil is a popular product today because of two attributes. First, it is a naturally extracted substance.
Next, the formula cures in five to 30 days, producing a robust and easy-to-maintain finish. Thus, you can use it on floors and boat decks.
The oil requires dilution with hydrocarbon thinner to reduce its viscosity. This way, it can penetrate the most refined wood grain.
The thinning solvent evaporates within 15 to 20 minutes. Hence, you won’t affect the product’s efficacy.
Tung oil cures slowly into a light/matte satin finish with a slight golden tint.
Moreover, the color becomes more pronounced with multiple fine and thinner coats.
However, the formula resists water better than other pure oil finishes. It also does not darken noticeably over time.
Woodworkers believe that tung oil is less vulnerable to mold than linseed oil.
In addition, it works better on sculptures near waterways.
Also, heat the oil to 500 degrees Fahrenheit in an oxygen-free space to increase its viscosity.
The exercise also enhances the product’s film-forming quality.
Alternatively, you can mix polymerized tung oil formulas with mineral spirits. This way, the oil is user-friendly.
Or you can go for D-limonene and Limonene, which are less toxic.
Tung oil comes in variations depending on the manufacturing process. Only pure tung oil remains free from thinning and is non-toxic.
The two primary versions include:
Tung Oil Finish (or Modified Tung Oil)
This tung oil variation includes thinners, metallic drying agents, and less expensive oil additives.
Further, the solvents enhance penetration, shorten the drying time, and make the product affordable.
However, although these additions benefit the user, the formula no longer looks like or behaves like pure tung oil.
Besides, most products contain only a little tung oil, whereas some do not have any oil.
Polymerized Tung Oil
Woodworkers complained that tung oil takes a lot of time to cure thoroughly.
As a result, vendors introduced polymerized tung oil.
The formula undergoes a cooking process to complete the molecular activity partially.
Uses of Tung Oil?
Crafters, carpenters, and hobbyists love tung oil and use it to deliver a lovely and protective finish.
Moreover, the formula works on multiple projects and surfaces.
For instance, you can use it to finish concrete, brick, stone, bamboo, wood, and even metal surfaces.
Tung oil works excellently on cabinetry, siding, decks, wood floors, weathered lumber, furniture, handmade toys, and musical instruments.
Besides, the product protects the wood while delivering a hand-rubbed finish.
Also, tung oil does not sit on the lumber’s surface. Instead, it soaks deep into the wood fibers and delivers a lovely non-oily finish.
Thanks to the formula’s food-safe qualities, it is perfect for oiling wooden spoons and cutting boards.
In addition, you can comfortably use it on concrete and butcher blocks.
Tung oil provides a natural technique to finish kitchen cabinets and countertops.
Thus, it helps keep potentially hazardous formulas like lacquer and varnish at bay.
In summary, artists, tradespeople, and woodworkers use the oil product for:
- Waterproofing outdoor patio furniture and decks.
- Preserving metal crafts and art projects.
- Polishing canoe and boat oars to improve water resistance.
- Sealing indoor brick fixtures like fireplace mantels.
Pros and Cons of Tung Oil
Tung oil features multiple advantages, making it a go-to finishing product for various projects.
They include:
Non-Toxic
Tung oil is non-toxic and does not contain VOCs. The formula’s natural qualities make the formula a perfect finish.
Further, it comes from crushed tung tree seeds without artificial ingredients.
You can use the oil to make kitchen toys and kitchen utensils.
However, although it is perfectly safe on toys, please allow it to cure for 30 days before use.
Tung oil is pest and insect resistant. Thus, you can apply it to any woodworking project and expect no harmful effects.
Unfortunately, oxidation happens when you expose the formula to air. The activity produces aldehydes and hydrocarbons.
But these chemicals are in low concentration and thus not harmful to people and animals.
Waterproof
The formula is waterproof and protects furniture and other woodworking projects from moisture and water droplets.
It serves as a water-resistance coating on wooden surfaces and prevents moisture molecules from penetrating the wood grain.
Therefore, consider the oil for woodwork with no water resistance. As a result, your project is free from water absorption and remains dry.
However, please ensure that you deliver full coverage. Then, let the finish cure properly before application.
Tung oil’s components crosslink with atmospheric oxygen and polymerize, delivering a rigid, water-resistant coating.
Further, the finish absorbs 12 percent of atmospheric oxygen and forms robust waterproof skin.
Easy to Apply
Applying tung oil is pretty straightforward. Further, it delivers a durable and easy-to-maintain finish.
Even a woodworking beginner can apply the oil without issues.
Apply tung oil using a cloth or paintbrush along the wood grain. This way, the wood absorbs the formula faster.
Also, you need at least six coats for the best outcome. Then, ensure the wood dries after each coat application.
Generally, each layer needs about six hours. So, please be patient.
Below are simple tips to effectively apply tung oil.
- Sand the wood lightly and evenly with 220-grit sandpaper. Continue until you deliver a lovely smooth surface.
- Use a damp rag to clean debris and sawdust.
- Apply the first tung oil coat with a paintbrush without missing spots. Also, follow the wood grain for a professional result.
- Let the lumber dry for more than six hours.
- Sand the first tung oil coat and apply the second layer. Use a 660-grit paper dipped in the formula for better absorbance.
- Give the wood several hours to dry and repeat the process till the sixth coat.
Food Safe
Tung oil comes from tung nuts and is thus 100 percent food safe.
Also, you can apply it to kitchen utensils such as butcher blocks, bowls, baskets, countertops, and cutting boards.
Please give the finish 30 days to dry. Otherwise, the product’s chemical ingredients can release from the surface, causing lots of trouble.
The oil also serves as a grain filler and keeps moisture from penetrating the lumber.
As a result, it stops bacterial and fungi growth, making the lumber food safe.
Finally, pure tung oil does not contain VOCs hazardous to vegetables and meat.
You can count on it to deliver superior protection for wood and your health.
Elasticity
Although tung oil hardens well, it is incredibly elastic and flexible. Thus, the finish will not crack easily, increasing the wood’s lifespan.
In addition, the oil layer expands and contracts with the wood at various temperature levels.
As a result, it does not lose its stability.
The formula’s elasticity does not go after curing and turning into a solid polymerized structure.
Moreover, this compatibility with wooden surfaces is exceptional, reducing dull spots and scratches.
Attractive Color
The oil features a naturally transparent hue. But it takes time to penetrate and change the wood’s appearance.
In addition, tung oil delivers a deep golden rich tone with a wet floss look after application.
However, it is prudent to exercise patience as you get a lovely glossy finish by applying eight coats.
The extra sheen enhances the woodwork’s beauty.
Further, the oil does not give a plastic-looking shine. It only improves the lumber’s natural sheen.
Tung oil also enhances a darker surface with a warm, rich hue, giving a pleasant feeling.
Lastly, consider sanding the finish with 600-grit paper for a smoother surface. However, ensure the formula dries appropriately first.
Resistant to Acids and Alcohols
Tung oil is resistant to acids and alcohol, making it popular for desk countertops and cutting boards.
Also, the finish is resistant to dust, acetone, vegetable acid, and fruit acid.
For instance, an accidental orange juice spill will not penetrate the lumber. Therefore, you won’t destroy the tung oil film.
Doesn’t Yellow Over Time
A Tung finish oil does not turn yellow or become rancid over time. Hence, you can keep the wood’s color for a long duration.
This attribute distinguishes the formula from polyurethane, linseed oil, and varnish products.
Linseed oil is susceptible to discoloration. It also requires frequent maintenance to remain in good shape.
Lastly, tung oil does not change its hue under any circ*mstances. Thus, maintenance costs are low.
On the flip side, tung oil has drawbacks to consider. This way, you can avoid mistakes and deliver a fine finish.
Slow Penetration
Tung oil’s penetration is relatively slow. Further, unlike other finishes, it needs at least six coats to deliver a durable finish.
This aspect is so time-consuming and requires lots of effort.
Moreover, you need to sand between each oil coat for effective finishing. And the drying time for each layer is about three to four days.
So, you also need some patience to complete the job.
Long Processing Time
Unlike many other finishing formulas, tung oil takes 30 days to cure properly.
Also, please do not position the project under direct sunlight to avoid ruining it.
Ensure you check the woodwork frequently during the first ten days and wipe off the formula seeping to the surface.
Tung oil’s long processing time is a primary drawback you cannot skip. Please be careful.
In addition, please avoid placing heavy items on the surface. Otherwise, it will become tacky, and you will have difficulty removing the particles.
Unpleasant Odor
Tung oil produces a distinctly unpleasant odor for a few days until it fully cures.
Hence, consider wearing a mask when applying the formula to avoid respiratory problems.
The smell goes away over time when the coating dries. But you can dilute the odor with mineral spirits to mask it.
Expensive
The oil is relatively pricier than other similar finishing formulas like linseed oil.
Generally, tung oil is about 25% more expensive than polyurethane, varnish, and some paints.
But you can save money when buying tung oil in more significant amounts for extensive woodworking applications.
Doesn’t Smoothen the Wood Grain
A tung oil finish cannot smoothen a rough wood grain. Thus, wet sanding the surface after each coat is advisable.
In addition, the process removes brush marks and facilitates a professional finish.
Difficult to Store
Please avoid storing tung oil under the sun as it reacts with light and heat, ruining efficacy.
Fortunately, although storing the product is challenging, a dark area with room temperature conditions does the trick.
With time, the tung oil container forms a film or gummy-like deposits around the lid’s corner.
Unfortunately, you cannot use the formula at this point. The deposits show that the oil’s chemical structure is compromised and non-reversible.
Remember that a mistake can ruin the whole project. Therefore, please go through the advantages and disadvantages again to minimize errors.
How Long Does Tung Oil Finish Last?
Tung oil can last as long as the project. However, ensure you adhere to recommended application and maintenance tips.
Apply four to eight coats to deliver a protective finish. Rushing the process or using thick coats causes wrinkling.
Also, regular tung oil reapplication is a must!
Depending on the workpiece’s purpose, you can consider reapplying tung oil once every six months or annually.
For example, surfaces experiencing light use will remain intact with annual reapplication.
On the other hand, furniture in outdoor spaces needs frequent maintenance. It faces constant exposure to elements, threatening its durability.
How to Apply Tung Oil To Wood
Tung oil is a natural drying oil commonly used in woodworking finishing applications. Further, it hardens to protect and enhance the wood’s luster.
Apply the formula after sanding and cleaning the lumber. This way, the previous finish will not compromise the outcome.
Also, spread the oil along the grain pattern with a clean, lint-free cloth. Then, allow it to soak into the wood for an hour.
Below are practical tips to get a lovely and durable finish.
Prepare the Wood
Preparation is the very first step of tung oil application:
Clean the Wood Surface with a Damp Rag
Damp a clean rag with warm water and squeeze out the excess moisture.
Next, wipe the surface using smooth circles or long linear strokes and follow the wood grain.
Give the lumber a few minutes to dry.
Clear the surface of dirt, oil, dust, and other messes to accommodate tung oil.
In addition, wiping the wood raises the grain, making sanding more effective.
As a result, you deliver a smoother overall finish.
Strip the Existing Finish With Trisodium Phosphate (TSP).
Removing varnish and lacquer finishes is advisable before applying tung oil.
Mix one water gallon with two TSP tablespoons. Then, use a sponge or brush to spread the mixture on the surface.
Let the surface dry before further handling.
Although Trisodium Phosphate is a powerful deep cleaner, it is highly toxic.
Therefore, always wear a facemask, a respirator, rubber gloves, and long-sleeved clothing when handling the chemical.
In addition, strip the lumber in a well-ventilated area or outside, if possible. This way, you keep the fumes from becoming overbearing.
Sand Thoroughly
Run 120-grit sandpaper over the surface using tight circles. The exercise will help smooth out grain imperfections and inconsistencies.
Sand all the recessed nooks, corners, and edges to guarantee a uniform finish.
Also, please note that sanding facilitates better adhesion.
Wipe the Sanded Surface
Use a cleaning cloth to wipe the sanding dust. Further, ensure the wood is debris-free and allow it to dry before applying the formula.
Consider a thin, dry paintbrush to remove stubborn particles from grooves and creases. Otherwise, dust particles may create an imperfect finish.
Cover the Work Area With Tarp or a Dropcloth
A dropcloth serves as a protective buffer for the surrounding area. Thus, you can work quickly without worrying about an oily mess.
Also, you’ll only have to remove the cover and spray it off after the project.
Alternatively, use a few newspaper sheets when you do not have the above accessories.
Lastly, rich natural oils, such as tung oil, leave permanent stains on absorbent materials. So, cover the workspace, if possible.
Coat the Wood
-Thin Tung oil With a Solvent
Stir equal parts of tung oil and turpentine, mineral spirits, or organic citrus solvents.
This exercise makes the formula easier to apply in thin coats. And as a result, you deliver a glossier and more durable finish.
Fortunately, you do not need more than a single tung oil canister for most minor projects.
Moreover, a quarter gallon can cover up to 100 square feet.
However, do not thin tung oil when treating surfaces used for culinary surfaces, such as cutting boards, countertops, and spoons.
Although the formula is naturally non-toxic, additional solvents leach into the food, making it harmful to ingest.
-Soak up the Oil with a Clean, Lint-Free Cloth
The best way is to press the folded rag over the bottle’s mouth. Then, turn the can upside down.
The escaping oil creates a neat, round daub and helps keep your hands clean.
In addition, you will control where the finish ends up better than if you poured it directly on the surface.
Alternatively, apply the formula with a sponge or wide-tipped bristle brush.
Either way, you’ll deliver a good finish.
-Rub the Formula in the Wood Grain Direction
Working along the grain accentuates its subtle natural patterns.
Aim for uniform coverage across the surface and continue polishing until the initial shine and slickness disappear.
In addition, cover the workpiece’s legs, underside, edges, and corners.
You can also apply little oil to drawers and cabinet doors for a more consistent look.
-Apply the Oil Liberally
Go a little heavy for the first coat. Besides, unfinished lumber absorbs more oil, leaving very little after.
Remember, the wood should appear wet and silk but without oil pools.
On the other hand, please avoid oversaturating the wood with one application. Instead, layer several coats for better results.
-Let the Tung oil Finish Dry.
Give the wood at least 30 minutes to dry. The oil penetrates deep into the wood grain as it sits, eventually solidifying.
Please do not touch the wet finish and give it one to two hours, if possible. More time means better absorption.
Accidental dents and scratches on the fresh finish may remain visible even after drying.
-Wipe Off the Excess Oil.
Glide a clean cloth over the wood to clear the remaining traces. But ensure that the project has enough time to absorb the formula.
You can decide to add more coats depending on the workpiece’s intended use and the desired color depth.
Lastly, look out for wet areas glistening in grooves and depressions.
-Facilitate a More Durable Finish
Let Surface Rest Between Coats
The recommended resting duration is three to seven days as tung oil cures slowly.
In addition, consider waiting for a week after each application to guarantee the best outcome.
The duration also ensures the follow-up coat bonds well to the previous one. Hence, they can harden separately.
Most applications need between four to six tung oil coats.
Moreover, more layers deliver a more lustrous surface. In addition, you are sure of a more protected project.
Please note that applying tung oil is an ongoing task. Therefore, take your time and apply each coat correctly.
-Sand the Wood Lightly Before Adding Another Coat.
Make a few passes over the lumber when you are ready to add an oil coat.
Use 320 to 600 grit paper or oooo grade steel wood for the best outcome. But gently buff the surface in all directions to avoid ruining the existing coat.
The objective is to scuff up the finish to enhance adherence.
Also, dust off the lumber thoroughly after sanding.
-Give the Oil Several weeks to Cure Completely.
Put the workpiece away to allow the finish setup. Further, wait for ten to 15 days before exposing the lumber to pressure or moisture.
The surface solidifies enough to allow regular use.
Also, newly finished wood cures faster in a cool, dry environment.
Here’s How How to Apply Tung Oil:
Is Tung Oil Water Resistant?
Tung oil is waterproof and guarantees superior wood protection from moisture penetration.
Further, the formula absorbs 12% of atmospheric oxygen to create a waterproof coat. So, it is safe to apply on various surfaces regardless of the material.
Tung oil reacts with oxygenated air. Then, it crosslinks and polymerizes to deliver a thin, water-resistant finish.
Does Tung Oil Need a Sealer?
You do not need an additional sealer because tung oil naturally seals the surface. As a result, you enjoy waterproof protection.
The finish is among the most water-resistant oils and stands out as a durable final finish.
However, a more rigid top coat is advisable if the surface undergoes heavy use.
Still, you can top coat a tung oil surface. But let it cure for at least 36 hours before adding the final layer.
Tung Oil Vs Linseed Oil
We have considerable differences between Tung and linseed oil.
For instance, the former delivers a transparent surface, whereas the latter yellows over time.
In addition, tung oil offers more durability, water resistance, and faster curing times, while linseed oil is more flexible and easier to apply.
Follow the distinction below for a better understanding.
Water Resistance
Tung and linseed oil are water resistant, thanks to tight crosslinks between molecules. However, they can collapse under prolonged moisture exposure.
Further, the formulas cannot stand against other finishes in water resistance.
For example, despite the proper application, Shellac, Lacquer, and Varnish consistently outperform Tung and linseed oil.
Drying Times
Tung oil and linseed oil drying durations depend on the specific product.
Usually, tung oil needs between two to three days to dry thoroughly. But some brands only require a day if you need fewer coats.
On the other hand, linseed oil’s drying time heavily relies on variation.
Boiled linseed oil needs one to three days to cure, while Polymerized linseed oil only needs a day.
Manufacturers measure pure linseed oil’s drying duration in weeks, not days.
Besides, some surfaces may take four to six weeks, depending on the coats applied.
Finish
Tung oil produces a matte finish after curing. Further, it does not give a noticeable sheen.
A matte surface makes certain imperfections less visible. In addition, it ensures the sheen will not compromise the wood’s natural beauty.
Conversely, linseed oil delivers a noticeable shine. But the surface is less glossy and akin to a paint’s satin finish.
Some woodworkers enjoy the formula’s slight glow. It adds some visual dimension to the workpiece.
The finish also adds a traditional feel to furniture pieces.
Safety
Generally, tung oil is safe for humans and pets. Hence, you can apply it to high-contact flooring and furnishings.
Moreover, the product is food safe, making it perfect for food serving pieces, dinnerware, and storage containers.
On the other hand, linseed oil’s safety depends on the type.
For instance, pure and polymerized versions are safe for food, people, and pets. But boiled linseed oil releases VOCs and has harmful compounds.
Color
Tung and linseed oil have a slightly yellow hue.
However, the former does not yellow the lumber. Instead, it dries into a transparent finish, preserving the wood’s original color.
Conversely, linseed oil may deliver a slight yellowing initially.
Also, although this aspect is not a concern, the hue can transition into an orange one.
As a result, the wood’s final look changes dramatically as weeks and months go by, perhaps to an uncomfortable state.
Application
Tung oil is non-toxic and eco-friendly. Further, it is a solid choice for various woodworking projects.
Toys, furniture, cutting boards, musical instruments, butcher blocks, and floating benefit from the oil.
Oppositely, please exercise caution with boiled linseed oil.
It is not suitable for musical instruments, children’s toys, or items in contact with food.
However, the formula works well with cabinetry, furniture, and similar workpieces.
Pure or polymerized linseed oil gives you more options. They are non-toxic, allowing you to apply them the same way as tung oil.
Durability
Tung oil outperforms linseed oil as far as durability goes. In addition, the formula is mold and mildew-resistant.
The oil dries into a hard surface and does not scratch quickly. Also, repairing these scratch marks is easy.
On the other hand, linseed oil is flexible. Besides, it is ideal for multiple woodworking applications involving softer woods.
Thanks to its swelling and contracting abilities, you can use the formula in various weather conditions.
However, linseed oil is not as durable as its counterpart.
In addition, it is easier to scratch and does not work well for high-touch furniture or high-traffic flooring.
Lastly, linseed oil is susceptible to mold and mildew, depending on the brand.
Number of Coats
Here is one area where linseed oil outshines tung oil.
In most cases, you only need one to two coats to deliver an excellent surface. Also, although you may require a third layer, it is not necessarily typical.
Conversely, tung oil needs four to six coats to deliver a durable finish. Moreover, more oil layers guarantee longevity.
Ease of Use
Tung and linseed oil are easy to use.
However, boiled linseed oil introduces a new dynamic. You need extra precautions to guarantee safety, as the formula has harsh additives.
For instance, use a respirator, mask, gloves, and eye protection when using the formula.
Price
Regarding cost, Tung and linseed oil are almost the same. Further, the end price is pretty similar.
However, the most significant variance sets in because of grades and brands.
In addition, tung oil needs more coats than linseed oil, making the cost higher.
Thus, factor in the project size. More extensive furniture items, sizable flooring, and numerous cabinets need more formula.
Should You Sand Between Coats of Tung Oil?
It is okay to sand between tung oil coats. But there is a caveat.
Give each coat enough time to dry. Otherwise, you’ll ruin the previous surface.
Also, please avoid sanding the final coat. The surface will deliver a smooth finish if you sand between coats.
Frequently Asked Questions
The questions include:
How Many Coats of Tung oil Should I use?
Generally, you need six tung oil coats to deliver a professional finish. But remember, the formula features poor absorbance and a slow curing speed.
Also, the needed oil coats depend on the wood type, the sheen level, and desired glossiness.
So, apply as many coats as possible till you get a satisfactory outcome.
Is Tung oil Good for Cedar?
Tung oil works excellently on Cedarwood. Further, it delivers a superior protective coat and a dark rich appearance.
In addition, you can use it on multiple cedar applications, such as panels, frames, sidings, fences, and musical instruments.
Follow the wood grain when applying tung oil for better results.
Can I Paint Over Tung oil?
You can paint over a tung oil surface.
First, clean the wood with water and soap. Then, lightly sand and seal the surface with a primer coat.
As a result, you can apply paint over the finish without issues.
Remember, tung oil is an oil-based product. Therefore, use an oil-based paint to guarantee compatibility.
Can I Use Tung oil Over Stain?
You can apply tung oil over stained wood. However, ensure the formula is oil-based to deliver a successful outcome.
In addition, the oil does not work well with water-based stains.
Lastly, stain formulas give the furniture a lovely appearance. But tung oil protects against elements, like insect attacks and moisture.
Conclusion
Tung oil refers to a plant-based oil used as a lumber finish. It dries quickly into a transparent surface, enhancing and protecting the wood’s beauty.
The formula is among the oldest and most popular woodworking products. But most users are unaware of:
Tung Oil Advantages and Disadvantages
Artisans consider tung oil for many applications. It is non-toxic, eco-friendly, and does not yellow like linseed oil, polyurethane, nitrocellulose, and lacquer.
However, the product has disadvantages to beware of, like its high cost and vulnerability to stains, scratches, and water rings.
Tyron Otieno
Tyron is an avid woodworker and writer. He founded this website to help other woodworkers, whether hobbyists or professionals by sharing his knowledge and experiencie after a decade of woodworking.
