Wood Finishes

NON REVERSABLE FINISHES The following finishes cannot be reversed a) Resin Oil Varnish and Oil based paints. b)Pre-Catalysed Celloluse Lacquers, c) Acid-Catalysed Celloluse Lacquers, d) Polyurethane Catalysed Celloluse Lacquers, e) Polyester Lacquer.

OIL FINISHES After producing a good finish to the bare surface by sanding etc. STOP THE LATHE and apply a liberal coating of your preferred oil with a soft cloth. The oil could be any of the frequently used oils such as Teak oil for dark wood, or a clear mineral oil for lighter coloured timbers such as Danish oil, Tung oil, Walnut oil, or even Cooking oil. My own favourite is Danish oil which, I use whenever I can depending on the item.
RE-START THE LATHE and take a fine piece of sanding paper (Silicon Carbide) say 320 grit or less and literally sand the oil coating into the grain of the wood surface, not only is this a very enjoyable operation but it produces a really good filled surface and ultimately better finish.
STOP THE LATHE and apply another coat of oil. START THE LATHE and use a soft cloth to friction dry the item, an additional optional process is to burnish the piece whilst rotating with a handful of the SAME WOOD shavings. The result will be a durable waterproof finish that will only require the occasional coat of oil to refresh the surface.
I have found that Ash treated as above will after a couple of years if periodically given a light refresher coat of oil produce a finish that looks as good as any polished surface and also feels very natural.
OLIVE OIL Often recommended for Salad bowls etc. but never dries, walnut oil is better.

PARAFFIN WAX A mineral wax made from paraffin oil, it is a cheap soft clear white wax used usually in combination with other waxes to produce a soft polish for use on furniture and flooring.
PEANUT OIL Never dries
POPPY OIL A quick drying finish, available from some artist supply stores but very expensive.

REVERSABLE FINISHES A reversable surface coating can be dissolved in its own solvent, for example methylated spirits will reverse or dissolve standard shellac finishes such as French Polish. Cellulose thinners will reverse nitrocellulose finishes, and turpentine will reverse wax or oil finishes.
Reversable finishes include, a) Shellac, French polishes, Sealers. b)Nitrocellose, clear and pigmented, satin or gloss. c) Wax and Oil finishes.

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SHELLAC Shellac is a genuine organic product and can be used as a sealer, a polish, a binder for fillers. Shellac flakes are usually mixed with a spirit based product to produce substance that dries very quickly and leaves a very hard surface coating. Some woodworkers still make there own French polish by dissolving Shellac flakes in methylated spirits, but it is now readily available in different forms.
Shellac based finishes After producing a good finish to the bare surface by sanding etc. STOP THE LATHE and apply a gentle coat of Shellac based sealer follow the instructions on the container if this is a purchased filler, this will usually state that the coating should be left to dry for at least 15 to 30 minutes, but if you can be patient (and it pays to be) leave it until the following day or at least over night. When dry use a piece of Silicon Carbide sanding paper about 320 grit which has been dipped in Oil or Wax the choice will depend on your planned final finish. START THE LATHE and use this to remove any excess or uneven surface of filler, follow this with a piece of 0000 Wire Wool dipped in the same oil or wax to give a smooth well filled surface.
The final finish to this sealing process can be Oil or Wax depending on your choice, if oil just simply burnish with a soft coated cloth and then dry with a second cloth both with the lathe running, if Wax use a commercial wax polish or a mixture of Beeswax and Carnauba wax, if a Satin finish is required this can be cut back with a 0000 grade Wire Wool.
CAUTION never apply a Petroleum based wax over a shellac based sealer.
SOYA OIL Moderate drying capability
STOPPING Term used for the application of a wax based filler which results in a sealed surface prior to further processes such as polishing.
SUNFLOWER OIL Quick drying oil

TUNG OIL (China Wood Oil) Tung oil is derived from the seeds of several species of Aleurites, primarily Aleurites fordii, a deciduous shade tree native to China. It belongs to the Euphorbia Family (Euphorbiaceae) along with the candlenut tree (A. molucanna), another species with seeds rich in unsaturated oils. For centuries tung oil has been used for paints and waterproof coatings, and as a component of caulk and mortar. It is an ingredient in "India ink" and is commonly used for a lustrous finish on wood. In fact, the "teak oil" sold for fine furniture is usually refined tung oil. Some woodworkers consider tung oil to be one of the best natural finishes for wood. Other unsaturated plant oils, such as castor oil and linseed oil, take longer to dry and leave an oily residue until they soak into the wood surface. Tung oil 's ability to dry quickly and polymerize into a tough, glossy, waterproof coating has made it especially valuable in paints, varnishes, linoleum, oilcloth and printing inks.
Tung oil can be applied with a cloth or brush and leave 15 minutes before buffing and 24 hours before use
The oil-rich seeds are the source of tung oil, which is composed primarily of eleostearic (elaeostearic) acid, with smaller amounts of oleic, linoleic and palmitic glycerides. Eleostearic acid is a crystalline unsaturated fatty acid that exists in 2 stereoisomeric forms: An alpha acid occurring as the glycerol ester especially in tung oil, and a beta acid obtained from the alpha acid by irradiation (9, 11, 13-octadecatrienoic acid). For more info about the use and supply of Tung Oil CLICK HERE

WALNUT OIL This is my most favourite finish and was the traditional French furniture polishing oil, not only is walnut oil edible it is delicious and can be obtained from health and food stores often much cheaper than modern finishing oils and mixtures. It has a pleasant odour and is non toxin and dries quickly making it a safe finish for all types of use where safety is of concern. Walnut oil also penetrates deeply into the wood and can be reapplied over time a gloss finish can be obtained and it is moisture resistent. the only drawback is that you have to wait for the gloss finish to be obtained but in my opinion well worth the wait.