The oil finish is one of the most traditional approaches to completing your project. While it does not provide as much protection as more modern finishes such as varnishing, oil finishes bring out the natural beauty of the wood better. If you want to stain the wood prior to oiling it, use a water-based stain as oil-based dyes will clog-up the wood's pores, thus stopping the oil finish from soaking in effectively.
Safety Note: Never leave an oily cloth rolled up. As the oil oxidizes it generates heat and it is not unusual for the cloth to spontaneously combust. Even if you intend to throw the used cloths away, you must first allow them to dry, unrolled, outside.
There are four main types of oil covered below: linseed, Danish, teak and mineral. We also include a reader review of Organoil.
A linseed finish takes a considerable amount of time to dry and new wood will need several coats in order to produce a satisfactory finish. Boiled linseed oil takes "only" one day to dry and, as such, is a more popular option. Pure linseed oil takes about three days to dry, but provides better protection. Neither type of linseed oil is suitable for outdoor projects.
Apply the oil with a cloth and rub well into the wood. Leave at least 24 hours between applications. Once you are satisfied with the finish, buff with a soft cloth.
Danish and Teak Oils
Danish and Teak oils take less time to dry than linseed (thank goodness) and also provide a more resilient finish. Both oils are better suited to new projects than linseed, and it is best to relegate linseed to the older projects that already have linseed on them. Teak oil provides a slight surface sheen while Danish oil leaves a low luster.
Apply these oils with a soft cloth of brush and do not apply too much oil at a time (as it will not soak in). In between coats of oil, sand the wood down with a fine silicon-carbide paper. Typically, it is best to use four coats of oil.
Mineral oil is a laxative that is readily available from any chemist. Although this will not provide the same level of sheen as the above oils, it is ideal for projects such as cutting boards when you need a non-toxic substance.
The below feature on Organoil was contributed by Gregory McGrath, Bunbury, Australia.
Organoil is a specially formulated finish made from pure plant oils and a highly-refined white beeswax. The underlying foundation of the product is Tung Oil.
I discovered this product at a timber and woodworking show in Perth, Western Australia. It is the type of finishing process that appeals to me as it is easy to apply to large projects. What is more, the process is not too time sensitive and can be completed over several days at your own leisure.
The added benefit of using this particular product is the rich, sweet aroma that fills your workshop while you are working. It smells wonderful and the finished wood presents a wet look, highlighting the wood's natural patterns and grains. The oil penetrates deeply into the wood, enhancing its natural color. This process is especially suited to grain- and character-enriched timbers. I have used it with impressive results on Sheoak, Blond, Pink and Red Jarrah to date. The oil finish also allows the wood to age and darken naturally over time.
The oil is applied through a technique known as wet-on-wet burnishing. This technique requires the wood to be sanded down through the various degrees of smoothness until you reduce the grit down to 600 or 800 grit wet and dry sandpaper. At this stage the wood begins to show a slight lustre. Don't lose the extra fine sawdust from the last piece of sandpaper that you used as this will serve as a fine filler when you apply the oil.
Apply the oil to the wood surface, allowing to soak in for a few minutes. Then, using the last piece of fine sandpaper (which has the extra fine sawdust in it still) start to massage (or burnish) the oil into the wood's surface. If the surface becomes too dry, add more oil. Once the entire surface has been oiled, the wood should have a satin finish. At this point you can apply a Natural Wax Oilish to bring the surface to a lustre. Do not add a second finish until the wood's surface is completely dry.
Alternatively, continue sanding the surface with 1200 grit paper, adding more oil as needed. Two or three sanding/oil combinations may be needed to arrive at the ultimate finish.