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Transparent finishes for wood

There has been a tremendous growth of interest in transparent wood finishes which enhance timber rather than hide it under paint. Also, with the restrictions placed upon the use of hardwoods, there has been a marked rise in the popularity of materials that imitate these woods while using the more sustainable softwoods.

As colours can change when finishes are applied, test out any chosen dye and finishing coat on a piece of scrap material - this will also ensure that there is no reaction between the stain and the covering coating.

Remember that faults and blemishes in the material will be enhanced, not hidden, so very careful preparation is needed to achieve a natural finish.

Dyes and wood stains

Oil

These are slower to dry than water based and they do not penetrate so deeply. However they are less likely to produce overlap marks. Allow plenty of drying time, and then seal the surface with shellac.

Stain preservatives

Often used for exterior timbers where protection is required as well as an attractive finish. They normally include a fungicide to inhibit mould growth. They tend to be very thin and soak into the timber and are far less prone to peeling. They can be used on sawn bare or previously stained wood.

Water based

Easy to use and resistant to fading, they are best applied after the surfaces have been sanded and the surface dampened with water to raise the grain. After application, seal with a coat of sanding sealer before applying a finish.

Varnish with stain

These have a polyurethane varnish combined with a wood stain, so the stain tends to sit on the surface of the timber rather than being absorbed into it. Remember that each coat applied will darken the wood further. To maintain a light finish, it may be wise to apply a coat of clear varnish as a first coat or after the desired shade has been achieved. For a durable finish, always apply a thinned first coat so that it will 'key' into the timber..

Varnishes

Dust is a problem with all varnishes, specks of dust can ruin the look of an otherwise perfect finish. For a durable finish, always apply a thinned first coat so that it will 'key' into the timber.

Acrylic Varnish

Quick drying and non-toxic, brushes can be rinsed out in water. Available in gloss, satin and matt finishes.

Exterior Varnish

Specially formulated microporous varnish, which allows the wood to 'breathe'. Also, contains an ultra violet filter to reduce bleaching by the sun, and a fungicide to prevent mould growth.

Polyurethane Varnish

Gives a clear, tough surface, and is available in gloss, satin and matt finishes. Once fully hardened, they should not be marked by hot cups etc. being rested on them.

Yacht Varnish

A high gloss finish based on tung oil and phenolic resins, with extra durability and, as the name suggests, resistant to sea, fresh water and all climatic conditions. Very good for use on outside timber even when well away from the sea.

Polishes

The traditional finish for internal furniture

French Polish

Made from pure shellac and alcohol, and designed to give a good finish on furniture. In addition to standard French Polish, other options are available:

  • White Polish made from bleached white shellac.
  • Button Polish, made with button shellac, producing a more orange colour.
  • Ebony Polish, gives a jet-black finish when applied.
  • Garnet Polish, gives an attractive deep rich brown cast to wood.

French Polishing kits are available for the beginner.

Wax Polish

A good quality wax polish with added beeswax will gently lift and remove grime, and then leave a hard protective coating with a natural sheen The traditional wax has no added oils, colour or perfume. Wax Polishes are available in a number of forms including liquid, paste, a special brushing wax, coloured waxes and staining waxes.

Oils

Danish Oil

Excellent on pine, it is based on Tung Oil for extra protection and durability. It gives a natural low lustre finish.

Finishing Oil

Specially formulated to revive old woods, it can be used as an oil finish, or in preparation before wax polishing.

Lemon Oil

This provides a suitable finish for teak and matt finished woods where a wax finish is not desired. It has the aroma of fresh lemons.

Linseed Oil

A natural product available in natural and boiled form. Although a traditional finish, it is best not used for wood finishing (apart from cricket bats) as it goes gummy and sticky with age.

Teak Oil

Based on Tung Oil and added resins, it gives a quick drying penetrating seal to teak and similar woods. It leaves a slight sheen when dry.

Tung Oil

This oil gives a superior finish to that of linseed oil, and is water-resistant. It can be easily applied using rag.

Two part coating

These are cold cure lacquers, which need to be mixed together before application. They tend to be resistant to heat, solvents and abrasion. They can be polished to a high gloss finish or rubbed down to produce a satin or matt finish.

They give a VERY hard finish and can be susceptible to chipping and can be problematic to repair or remove.