Finishing gives the wood a protective layer that can manipulate and emphasize its color and character while keeping it clean and sanitized by sealing pores. It can be applied by brushing, wiping, or spraying, requiring skill and experience.
Different surface finishes offer various advantages and properties, making them suitable for multiple wooden instruments and preferences. They are typically categorized into three different types:
1. Walnut Oil
Walnut oil is an ideal finish for wooden kitchen utensils like bowls, butcher blocks, salad tongs, and wood handles. It’s safe to use on surfaces that come into contact with food, and it enhances the color and grain of the wood.
The first linseed oil coat takes about 24 hours to dry completely. It’s important to wait for this drying time because if another linseed oil is applied before the first one dries, it will never cure and leave a tacky or splotchy surface.
You should also thin the linseed oil for the first application. This helps it absorb into walnut wood quickly and avoids forming blotches upon drying. This is especially necessary since walnut oil has slow-drying properties. With the help of wood finishing services, you can thin it with mineral spirits or odorless thinner for promising results.
2. Mineral Oil
Although mineral oil can offer a natural finish and a good amount of protection for wood, there are some concerns to consider regarding this particular type of finish. Mineral oils are derived from petroleum and can raise environmental concerns. They can also clog pores and require frequent reapplication.
In addition, they don’t create a durable film on top of the wood and can become dull over time. For these reasons, many woodworkers choose other types of finishes, such as boiled linseed oil, to protect and enhance the beauty of their woodwork.
Boiled linseed oil also has a lower cancer risk and doesn’t irritate the skin when touched frequently. This makes it a better choice for woodwork that will come into direct contact with humans, such as wood countertops or cutting boards.
3. Carnauba Wax
Carnauba wax is a natural and biodegradable product, whereas some synthetic options can contain chemicals that are harmful to the environment. This makes Carnauba a good choice for eco-conscious customers.
This “Queen of the Waxes” is a naturally occurring wax extracted from the leaves of the Brazilian palm tree Copernicia Cerifera. It is harvested by sun-drying the leaves, beating them to loosen their powdery wax flakes, and then removing and separating them from the remaining leaf.
You can purchase traditional carnauba paste waxes in tin cans or more modern liquid forms that come pre-softened for easy application by hand or machine. This fast-drying finish provides excellent protection and can be used on all finishes, including bare wood.
4. Microcrystalline Wax
Microcrystalline waxes are derived from crude petroleum through refining or petroleum jelly (petrolatum). They have smaller crystals than paraffin waxes and contain higher proportions of iso-paraffinic and naphthenic hydrocarbons.
They are used as a topcoat over shellac, lacquer, drying oil, or varnish to protect against moisture damage. They are also used as a filler to repair scratches, dings, and pores in wood surfaces.
Many woodworkers choose wipe-on polyurethane, commonly called “poly” for short, because it is easier to apply than traditional oil finishes. Wipe-on poly is durable, stains well, and provides resistance to water, heat, and most other chemicals. However, it does not offer the same level of protection as true oils. It may also release volatile organic compounds into the air when it dries, harming your health.
5. Paste Wax
A wax finish can add beauty and durability to a wood surface. It can be used as a standalone finish, or it can be used as a topcoat over another finish like polyurethane, varnish, shellac, or lacquer.
Waxes are primarily made from either beeswax or carnauba wax. They are soft and can be easily spread onto a piece of wood with a rag. They also have a relatively low friction and produce a nice shine.
They don’t offer much protection from physical damage like scratches, though. However, they can protect from water stains and other chemical spills. Wax can be reapplied as needed and doesn’t yellow with time as some varnishes do. It’s an ideal choice for wood surfaces that will be used extensively.
6. Linseed Oil
Linseed oil is a traditional wood finish that deeply nourishes and protects wood with a flexible protection that can resist abrasions. It also offers good stretchability and elasticity. Wood expands and contracts as it changes from temperature to humidity, so a flexible oil coating helps it retain its shape.
Raw linseed oil (also known as flax oil) has a deep golden brown color and yellows slightly over time, which can accentuate the natural beauty of the grain on certain wood species. Boiled linseed oil has a higher viscosity and dries faster than raw linseed oil, which can help speed up the application process.
Another popular option is Danish oil, made from boiled linseed and tung oil. This type of wood finishing blend is non-toxic and environmentally friendly, making it a great choice for those looking for an organic, durable finish.
7. Shellac
Shellac is used as a clear coating on wood furniture, particularly exotic species such as mahogany and satinwood, to protect them without hiding their subtle color and grain. It was the finish of choice for fine woodworkers until hardy nitrocellulose and synthetic furniture polishes took over in the 1920s.
Shellac consists of dry, flaky flakes that are the secretions of a female lac beetle (Laccifer lacca) harvested from trees in India and Thailand. These flakes are mixed with alcohol and applied to the woodwork.
It is important to choose dewaxed shellac when using shellac, as it contains 3-5 percent wax, which could cause compatibility problems when used as a base coat under other products, like water-based polyurethane. When applying shellac, thinning it with mineral spirits helps reduce brush marks and orange peel while spraying.
Conclusion
Wood finishing is both an art and a science, requiring careful selection of the right products and proper application techniques. When chosen wisely, a finish can enhance the natural beauty of the wood while providing protection against wear, moisture, stains, and other damage.
Oil-based finishes like tung, linseed, and Danish oils offer deep penetration to nourish the wood. Shellac and lacquer provide a clear, durable coating. Paste waxes and carnauba add protection with a soft glow.
With the wide variety of options available, every woodworker can find the perfect finish to suit their project and preferences. Whichever finish you choose, proper surface preparation, thinning, application, drying time, and maintenance will ensure your handiwork retains its beauty for years to come. The end result will be woodwork that you can admire and enjoy for generations.
