tung oil and shellac are two popular wood finishes that are essential for woodworking. They are a coating applied to a wooden object’s surface to enhance its appearance and protect it from damage.
It can add depth, color, and character to the wood, highlighting its natural beauty and grain, and also provides a barrier against moisture, heat, scratches, and everyday wear and tear.
This guide is for both seasoned woodworkers and beginners eager to learn, so they can get to know each other better.
What is Tung Oil?
Tung oil, also known as China wood oil, is a drying oil obtained from the seeds of the tung tree. This tree is native to China, hence the name, but it’s now grown in various parts of the world.
Tung oil has been used for centuries as a water-resistant finish for wooden objects. When applied, it penetrates deep into the wood, hardening to form a protective and durable barrier.
One of the key characteristics of tung oil is its ability to enhance the wood’s natural grain, giving it a rich, warm glow. Tung oil is also waterproof, making it an excellent choice for items that may be exposed to moisture. However, pure tung oil can take some time to dry and may require several coats to achieve the desired finish.
What is Shellac?
On the other hand, Shellac is a resin secreted by the female lac bug, found in the forests of India and Thailand. This resin is processed and dissolved in alcohol to produce a versatile wood finish. Shellac has been used for centuries, long before the advent of synthetic finishes.
Shellac dries quickly and gives a shiny, glossy finish that many woodworkers love. It’s excellent for sealing wood, preventing stains and knots from showing through paint. Shellac is also food safe once dried, making it a popular choice for kitchenware and children’s furniture. However, it’s not as durable as some other finishes and can be damaged by heat and alcohol.
Tung Oil vs Shellac: A Comparative Analysis
When it comes to choosing between tung oil and shellac, it’s essential to understand their unique properties and how they can impact your woodworking project. Let’s break it down:
Tung Oil
Tung oil penetrates deep into the wood, providing a flexible and water-resistant finish. It enhances the wood’s natural grain, giving it a warm, rich glow. Tung oil is also highly resistant to moisture, making it an excellent choice for outdoor furniture or items exposed to water. However, it takes longer to dry than shellac and may require several coats to achieve the desired finish.
Shellac
On the other hand, Shellac dries quickly and provides a shiny, glossy finish. It’s excellent for sealing wood, preventing stains and knots from showing through the paint. Shellac is also food safe once dried, making it a popular choice for kitchenware and children’s furniture. However, it’s not as durable as tung oil and can be damaged by heat and alcohol.
In terms of application, both tung oil and shellac can be applied using a brush, cloth, or spray. They both require proper surface preparation, including sanding and cleaning the wood before application.
Applying Tung Oil Over Shellac
If you’re considering applying tung oil over shellac, here’s a step-by-step guide to help you through the process:
Step 1: Surface Preparation
Start by ensuring the surface is clean, dry, and free from dust or debris. If the shellac finish is glossy, lightly sand the surface with fine-grit sandpaper to create a slightly rough texture for the oil to adhere to.
Step 2: Apply the Tung Oil
Apply a thin coat of tung oil to the surface using a clean, lint-free cloth. Work in small sections, rubbing the oil into the wood toward the grain.
Step 3: Let it Dry
Allow the oil to penetrate the wood for about 15-30 minutes. Then, wipe off any excess oil using a clean cloth. Remember, tung oil takes longer to dry than other finishes, so be patient.
Step 4: Repeat
You may want to apply several coats of tung oil for a more durable finish. Allow each coat to dry thoroughly before applying the next one.
Precautions:
Always test the process on a small, inconspicuous area first to ensure the results are to your liking. Also, remember to dispose of any oil-soaked rags properly, as they can spontaneously combust if not handled correctly.
Applying Shellac Over Tung Oil
Applying shellac over tung oil can create a beautiful, durable finish that combines the best of both worlds. Here’s a step-by-step guide on how to do it:
Step 1: Surface Preparation
Ensure the tung oil finish is completely dry before applying shellac. This may take several days depending on the number of coats and the environmental conditions. Once dry, lightly sand the surface with fine-grit sandpaper to ensure the shellac adheres properly.
Step 2: Mix the Shellac
Shellac often comes in flake form and needs to be mixed with denatured alcohol. Follow the manufacturer’s instructions for the correct ratio and allow the mixture to dissolve completely.
Step 3: Apply the Shellac
Applying a thin coat of shellac over the tung oil using a high-quality brush, working toward the wood grain. Allow the shellac to dry completely, which usually takes about an hour.
Step 4: Repeat
For a more robust finish, apply several coats of shellac, sanding lightly between each coat once it’s dry.
Precautions
Always work in a well-ventilated area when using shellac, as the fumes can be strong. Also, test the process on a small, hidden area first to ensure you’re happy with the results.
Tung Oil vs Other Oils: Comparing with Linseed Oil
When it comes to wood finishes, tung oil and linseed oil are often compared. Both are natural oils that penetrate the wood to provide a protective finish, but there are some key differences:
Tung Oil
Tung oil penetrates deeply into the wood and hardens upon exposure to air, providing a durable, water-resistant finish. It also enhances the wood’s natural grain and doesn’t darken as much over time as linseed oil.
Linseed Oil
Linseed oil, derived from the seeds of the flax plant, also penetrates the wood but doesn’t harden as much as tung oil. This results in a softer finish that may not be as durable. Linseed oil also has a longer drying time and tends to darken the wood more over time.
Related: Tung Oil vs Linseed Oil
In terms of application, both oils can be applied similarly, using a cloth or brush. However, tung oil often requires fewer coats for a durable finish than linseed oil.
The Role of Tung Oil in Woodworking
Tung oil has long been a favorite among woodworkers for its unique properties and versatile applications. It’s a hard-drying oil that penetrates deeply into the wood, providing a flexible, water-resistant finish that’s also resistant to alcohol and mild acids. This makes it an excellent choice for outdoor furniture, cutting boards, and other items that must withstand the elements.
One of the key benefits of tung oil is its ability to enhance the wood’s natural grain, giving it a warm, rich glow. It’s a finish that truly celebrates the beauty of the wood, making it a popular choice for high-quality furniture and woodworking projects.
However, tung oil is not without its drawbacks. It takes longer to dry than many other finishes, slowing the finishing process. It also requires several coats to achieve a durable, labor-intensive finish. Additionally, pure tung oil has a strong odor that some people find unpleasant, although this usually dissipates once the oil is dry.
The Role of Shellac in Woodworking
Shellac is another finish that holds a special place in the hearts of many woodworkers. It’s a natural resin dissolved in alcohol to create a versatile finish that can be used on various wood types.
One of the main benefits of shellac is its fast drying time. It dries to the touch in just minutes, allowing multiple coats to be applied daily. Shellac also provides a high-gloss finish that can be buffed to a brilliant shine, making it a popular choice for fine furniture and decorative items.
Shellac is also food safe once dried, making it a popular choice for kitchenware and children’s furniture. And unlike some other finishes, shellac can be easily repaired if it gets damaged, simply by applying another coat.
However, shellac is not as durable as other finishes, such as tung oil or polyurethane. It can be damaged by heat and alcohol, so it’s not the best choice for items that will be exposed to hot dishes or alcoholic beverages. Shellac also has a limited shelf life, especially once it’s been mixed with alcohol.
Food Safety Considerations: Tung Oil and Shellac
When it comes to woodworking projects that will come into contact with food, such as cutting boards, bowls, or utensils, the safety of the finish is a critical consideration. Both tung oil and shellac have properties that make them suitable for such applications.
Tung Oil
Pure tung oil is considered food safe once it’s fully cured. It doesn’t contain any additives or metallic driers, making it a safe choice for items that will come into contact with food. However, it’s important to note that not all products labeled as “tung oil” are pure; some may contain additives that are not food safe. Always check the label and opt for 100% pure tung oil for food-related items.
Shellac
Shellac is another finish that’s considered food safe once dried. It’s even used in the food industry as a coating for certain types of candy and fruit. However, like tung oil, ensuring that your shellac contains no non-food-safe additives is crucial.
Maintaining and Caring for Tung Oil and Shellac Finishes
Proper maintenance can extend the life of your tung oil or shellac finish and keep your woodworking project looking its best.
Tung Oil
Tung oil finishes can be maintained by applying additional coats of oil as needed. If the finish becomes dull or worn, simply clean the surface, apply a fresh coat of oil, and wipe off the excess. Regular maintenance is especially important for outdoor items to protect the wood from the elements.
Shellac
Shellac finishes can be easily repaired if they get damaged. Simply clean the damaged area and apply a fresh coat of shellac. Over time, shellac finishes may become dull or cloudy. This can often be remedied by applying a fresh coat of shellac or buffing the surface with a fine steel wool and a non-abrasive paste wax.
In both cases, it’s important to keep the finished items clean and dry when not in use, and to avoid exposing them to extreme temperatures or direct sunlight for extended periods.
Frequently Asked Questions About Tung Oil and Shellac
A few common questions often arise in our journey through the world of tung oil and shellac. Let’s address some of them:
Can I use tung oil and shellac on the same piece?
Yes, you can. In fact, many woodworkers use a combination of the two to achieve a specific look or level of protection. However, it’s important always to test the combination on a small, inconspicuous area first to ensure you’re happy with the results.
How long does tung oil and shellac take to dry?
Tung oil can take several days to cure fully, depending on the number of coats and the environmental conditions. Shellac, on the other hand, dries to the touch in just minutes, although it’s best to allow it to cure for a few hours before handling the finished piece.
Are tung oil and shellac safe for children’s furniture?
Both tung oil and shellac are considered safe for children’s furniture once fully cured. However, always ensure you use pure tung oil and shellac without harmful additives.
Conclusion
Tung oil and shellac are two unique finishes that can be used for various woodworking projects.
Tung oil has deep penetration and water-resistant properties, while shellac has fast drying time and high-gloss finish. The best choice depends on the project, personal preferences, and unique characteristics of the wood being worked with.
To ensure lasting beauty and protection, it is important to understand their properties, apply them correctly, and maintain the finish properly. This guide will help make informed decisions for future woodworking projects.