Linseed oil, also known as linseed oil, is one of the most popular wood finishes in the world. Like other hand-scrubbed oil finishes, linseed oil penetrates deep into the wood grain, protecting it from scratches and changes in humidity. It is easy to maintain, environmentally friendly and produces a satin finish that really shows off the color and grain of the wood underneath.
Linseed oil has often been replaced by synthetic alkyd resins (varnishes, polyurethanes and glazes) in recent decades, but has recently become popular again, mainly due to its non-toxicity and environmentally friendly properties. Unlike these synthetic alkyd resins, oil varnishes - including linseed oil - penetrate the grain of the wood rather than forming a film on the wood.
Common uses of linseed oil
We know linseed oil as a popular wood finish, but it has several other uses. Some of the most common uses of linseed oil include:
- as a finish for the preservation of wooden products, especially those that come into contact with food (e.g. cutting boards, wooden bowls, etc.)
- as a dietary supplement with many health benefits
- as an additive in oil paints that improves colour and workability
- as a means of cleaning brushes
- as a polishing and rust protection agent for metals
Advantages and disadvantages of linseed oil as a wood finish
Advantages
- Brings out the colour depth and structure of the wood grain
- Scratches and dents can be easily sanded out
- Non-toxic and environmentally friendly
- Penetrates deep into the grain and protects well against moisture fluctuations
- Can be used in conjunction with other finishes such as wax to further protect wooden furniture
Disadvantages
- Requires occasional re-oiling
- Susceptible to water rings
- The wood is more susceptible to scratches than a varnish or glaze (however, hard coatings are more susceptible to surface scratches which are more difficult to repair)
- Yellows slightly over time
- Fluctuations in temperature or humidity can cause the wood to "leak" oil.
- Susceptible to staining if colored liquids penetrate the wood
Linseed oil vs. Danish oil vs. Tung oil
As mentioned, linseed oil comes in several different varieties. Raw, polymerized and boiled linseed oil are all extracted from the linseed plant, but are processed to varying degrees. As a wood finish, linseed oil is often compared to Danish oil and tung oil.
Both Tung Oil and Danish Oil are terms that are often misused and misunderstood.
Tung oil is another popular wood finish derived from the seeds of the tung tree. It is native to East Asia and has been used as a wood finish for thousands of years. Pure tung oil dries faster than raw linseed oil and does not have the same yellowing effect, making it a good substitute for linseed oil on maple furniture. It is environmentally friendly, non-toxic, and food safe. It also dries to a much harder finish than linseed oil and is more water resistant. Tung oil typically requires 5 or more coats to fully saturate and protect the wood furniture. We recommend using 100% pure tung oil as it is often sold as a mixture with other compounds.
Danish oil is difficult to define. There is no one-size-fits-all formula for Danish oil. It's basically a catch-all term for any type of hand-rubbed finish that isn't 100% pure. Danish oil often contains tung oil or linseed oil along with various other ingredients - thickeners, thinners, drying agents, binders, and more. Typically, a finish with Danish oil is a mixture of some type of varnish and either tung oil or linseed oil.