There are many finishes woodworkers, and homeowners consider for their furniture and woodworking projects. Woodworking oils are some of the finishes you can consider for your finishing work. And in this case, the focus will be on tung oil vs linseed oil.
In recent years, linseed oil and tung oil are coming back in force. Many thanks to their non-toxicity and friendliness to the environment.
Choosing between these two finishes can be the most challenging task for anyone and even hard for first-time users.
However, from my experience with the two formulas and given a chance to choose between boiled linseed oil or tung oil for a finish, I would go for the boiled linseed oil.
The increased water resistance of tung oil is too little compared to the increased time and effort needed to achieve a presentable finish with the same tung oil. Tung oil will need about work with up to five or more coats.
What Is Tung Oil?
Tung oil refers to a plant-based oil that is used in wood finishing. This formula is clear, quick-drying, with high penetration into the grain to enhance and offer protection.
It is one of the oldest, most used, and most popular wood finishes derived from the tung tree in Eastern Asia.
Tung oil is appreciated by almost all the fine furniture craftsmen in the United States and other parts of the world, where woodworking takes center stage.
The formula is environmentally friendly, non-toxic, and above all, food-safe.
So how do you obtain tung oil? It is derived from squeezing and pressing the seeds of the tung tree, which is originally from Eastern Asia.
Like in the case of linseed oil, it is challenging to come across furniture that is finished using raw or 100% pure tung oil.
Therefore, you will find most woodworkers and other craftsmen using boiled or polymerized tung oil.
Pros of Tung Oil
Tung oil has been in use in the Asian region and worldwide for many centuries. And this can only explain how much satisfaction it offers to the users.
Some of the advantages that come with the use of tung oil include:
- Tung oil in its pure form is non-toxic
- Pure Tung oil is food safe
- You can easily apply this finish with a brush or cloth
- It is readily available
- You can easily to re-apply and maintain this finish in workpieces
- It offers so much resistance to ambient moisture
- The formula has a lot of versatility as you can use it on different surfaces like wood and stone
Cons of Tung Oil
As they say, nothing is perfect, and something good has its shortcomings. Tung oil is no exception. Here are some of the disadvantages of using tung oil.
- The formula resists water, but that does not make it waterproof.
- Strong impact affects and possibly damages tung oil, though not as bad as the same impact would do to linseed oil.
- It is expensive compared to the linseed oil
- You will need to apply more than one coat to notice the effect.
What Is Linseed Oil?
Linseed oil is also called flaxseed oil and is one of the most popular wood finishing formulas.
Linseed has a reputation for high and deep saturation into the grains of wooden structures. It offers top notch protection against scratches and variations in humidity in the process.
Thanks to its many impressive features, this formula is a preference of many. Linseed oil is eco-friendly with a satin finish that brings out the very best of the color and grain of the wood beneath it.
Raw linseed oil is the purest form of this fantastic finish. However, it does not make the best furniture finish as it has an extended dry time.
The linseed oil in its raw form would take up to weeks for a single coat to cure, making it less effective, especially if you are working on a short timeline.
Boiled linseed oil is, therefore, the most common of this wood finish; it does contain some level of potentially dangerous drying compounds.
Instead, the polymerized linseed oil makes the best finish if you want to use this oil finish line for your woodworking projects.
Pros of Linseed oil
- Linseed oil will enhance the natural texture of your wooden structure
- It further accentuates the wood’s grain
- The formula is non-toxic
- Linseed oil is food safe
- It is a deep penetrating oil
- This formula protects wood from moisture
- You can use linseed oil in conjunction with other wood finishes
Cons of Linseed Oil
- The formula requires a constant and routine application to remain in the best condition year-round.
- Surfaces with linseed oil are at greater risk due to impacts and other forms of abrasion
- The surfaces abrasion on the linseed oils is not easy to repair, unlike other coatings
- Failure to maintain wooden surfaces with linseed oil can result in yellowing
- Sudden changes in the temperature can result in the draining of excess oil by the saturated wood.
- This formula may fail to protect wood against inadvertent staining if you fail to re-apply regularly.
How to Apply Tung Oil to Wood
If you will use tung oil, it would be essential that you get it right in the application stage to avoid financial losses and redo the work, which culminates in a wastage of time.
Here are the steps that you should follow to apply your tung oil wood finish properly:
Preparation of the Work Surface Phase
In this phase, you need to conduct surface preparation in readiness for the next stage, coating.
The first thing you need to do is clean the surface using a dump cloth. I recommend wetting the cloth with warm water before wringing out the excess moisture.
Wipe down your wooden surface/structure against the wood grain in smooth circles. Once you are through this step, allow your wood enough time to dry.
The next thing after cleaning is stripping off the existing surface coating. Trisodium phosphate(TSP) has proven a great chemical stripper for wood surfaces.
It is best for surfaces previously covered with finishes like wood varnish or even lacquer.
You will need to mix about 2 tablespoons (29.6 ml) of TSP into a gallon (3.8 l) of water. Stir and then use a sponge to spread the liquid over the surface you intend to strip.
Note: You should avoid handling the solution until it dries on the surface because it contains some toxic chemicals when contact with the skin.
Precautionary Steps When Stripping With TSP:
Considering that TSP is highly toxic. I advise that you always have your protective gear on. Ensure you are on long-sleeved clothing, safety glasses, rubber gloves, and a respirator to avoid risks through chemical spillage.
Also, ensure that you are doing the stripping in an area with good ventilation to curb possible suffocation by the toxic fumes.
Once TSP has dried on your surface. The next step should be sanding.
Sand the surface properly with the help of high-grit sandpaper. I recommend around 120-grit or finer. Ensure that all the imperfections, as well as inconsistencies in the wood grain, are no more.
After sanding, the next step should be to remove the dust particles from the sanded surface after sanding. You can choose to use a shop vac before wiping off the surface.
Wipe to ensure that the surface is clean and free from any form of debris that might compromise the subsequent steps.
Use a thin, dry brush to remove stubborn particles from the grooves and creases.
The first thing you should do in this phase is thin your tung oil with solvent.
Here, you will need to stir equal parts oil and mineral spirits in one place or turpentine in a big bucket.
The purpose of thinning using the solvent is to make the formula easier to apply in several thin coats, which will result in a glossier finish with a lot of durability, unlike a single thick one.
As much as this oil is not toxic, chemicals used for thinning are dangerous when they come into contact food substances. That’s why I discourage thing oil for surfaces like kitchen tables.
Once you have thinned the formula, now take a clean cloth and use it to apply the formula to the wood.
Ensure that you are applying the formula in the direction of the wood grain.
Even as you apply your formula, be careful not to over apply on the wood with just one application.
You will realize the best result when you layer your formula on several coats.
Once you have applied your tung oil finish, allow it to sit for at least 30 minutes. In that time, the formula will penetrate deep into the wood grain and solidify in the long run.
Ensure that you are not touching the wet finish during the drying time.
For the very best result, I recommend giving your surface up to about 2 hours. As the formula gets more resting time, the structure will significantly absorb the oil, giving it an excellent finish.
In the event of accidental scratches or touching, it would help if you re-worked the affected surface when the formula is still fresh.
Wipe off the excess oil. Once you are confident that the oil has had enough time to soak in, take a clean rag and glide it over the surface of your structure any remaining traces.
Assess your finished structure to determine whether or not you are satisfied with the results. The purpose for which you use the wooden structure will decide if you are supposed to add more oil or not.
Once you apply the formula, allow the wooden structure to rest for 3-7 days between coats.
One thing about Tung oil is that it cures slowly. To realize the very best result, I recommend that you allow a single layer to sit up to a week after each application.
Such a move will ensure that the following coat bonds well with the previous one.
Most projects that apply tung oil will need between 4-6 individual coats. The more coats you apply to the surface, you will realize a darker, lustrous finish with maximum protection.
Note: Wood treatment with tung oil is a continuous process and may take days or weeks to realize the best results.
It would be best if you never considered it a one-time project as you may end up getting messed up after big spending.
After applying the first coat, you should always do a light sanding before moving to the next coat.
The goal of light sanding is to scuff it up just enough to facilitate the sticking of the next coat. Ensure that you properly dust off the wood following light sanding.
Repeat the above step until you are satisfied with the number of coats you have applied.
Once you are through, allow the oil to cure properly for several weeks. It will help if you let the wooden structure up to at least 2 weeks before exposing it to moisture or pressure.
Note: Use the above steps for the application of linseed oil!
Why Use Boiled Linseed Oil?
In most cases, woodworkers and craftsmen go for boiled linseed oil, but why? The popularity of boiled linseed oil in wood finishing cannot be understated.
Below are the significant reasons boiled linseed oil is beneficial:
When you work with boiled linseed oil, you get to bring out the texture and the color depth of your wood grain.
Additionally, linseed offers so much as you can use alongside other wood finishes, like enhanced protection to your surfaces.
Boiled linseed finishes are easy to repair in case of f damage during the application process. All you need to do is sand out any dents or scratches and then apply a new coat.
Finally, the oil comes with very deep penetration, allowing it to form an extended protective layer deep inside the wood.
Here’s How to Apply Tung Oil Finish:
How Long Does It Take for Raw Linseed Oil to Dry?
As stated before, Raw linseed oil makes an excellent finish for wood products if you apply it in thin coats and allow a lot of time to dry.
Typically, this oil can take between 2-10 weeks to fully dry, depending on the prevailing environmental condition.
Another factor that will determine the drying time of your raw linseed oil is the thickness of the application.
Tung Oil vs Linseed Oil
As I conclude this discussion, I would like to focus on the difference between these two finishes- tung oil vs linseed oil.
When pure, we know that linseed oil and tung oil are non-toxic, friendly to the ecosystem, and, above all, food-safe.
The two are plant-based with deep penetrate and saturation characteristics.
However, here are some critical differences between the two formulas:
- Linseed oil comes with a slightly yellow tint, while tung oil dries into a clear finish
- Tung oil dries into a stiffer, more durable finish compared to linseed oil
- Tung oil offers higher water resistance than linseed oil
- Raw linseed oil has a longer curing duration than pure tung oil
- Tung oil is generally more costly than linseed oil
If you want to use any of the two finishes on your wooden structure, you should find it easy to settle on one. I also want to imagine that most of your questions have answers in this guide.
However, if you have concerns that you would love to address, kindly feel free to reach out to me through the comment section below.