Staining, oiling, varnishing and waxing
Tips for staining beechwood manually.
Wood stains and finishing coats protect the wooden surface from dirt, prevent moisture from entering the wood, emphasize the colour and grain of the wood, accentuate its natural beauty and allow for an individual colour design.
All wood species are generally hygroscopic and absorb stain and lacquer in different ways depending on the porosity and cell structure of the species. European Beech is known for taking stains especially well. Due to the closed porous cell structure of beech, a very high quality of finish can be achieved. This opens up unlimited design possibilities for colour. Some examples are shown here, which have been obtained with wood stains of the company Becker Acroma ARTI GmbH. For beech, Becker Acroma is recommending the water-based staining system „ARTISTAR“. Apart from numerous standard colours, any colour tone can be produced individually.
In addition to the good machinability and high finish quality of European beechwood, it distinguishes itself by taking stains exceptionally well. Thus, other wood species like cherry, mahogany or walnut can be replaced by stained beechwood without problems.
With stains, a lot of different effects can be obtained. They can either accentuate the structure or have an equalizing effect. Accentuating stains will make the grain pattern of the wood even more vivid whereas equalizing stains may level it to the point of covering it up completely. And there are many steps in between so that it is possible with the help of stain to closely determine the degree of prominence of the grain pattern in the final product.
An important prerequisite of an impeccable staining result is a thorough sanding of the wood. While the mostly coarse pre-sanding is responsible for levelling the wooden surface and for removing rough spots like glue stains, the polishing process is providing the neccessary smoothness for an immaculate staining result. Final sanding is always done in the direction of the wood fibres, without exerting too much pressure, so that protruding wood fibers are not pressed down but rather cut off. One has to advise against fine-sanding at right angles to the wood fibres or circular polishing, which is recommended here and then. Unfavourable polishing marks will then be seen because stain will accumulate more at these blemishes. Also when pre-sanding with a coarse sanding paper,
it is not recommendable to sand at right angles to the direction of the wood fibres, because such sanding marks can hardly be levelled anymore during subsequent fine polishing, which results in a fidgety staining effect.
In series production, random orbital sanders have established themselves with subsequent dedusting with the help of double-cylinders. Good results can also be achieved with common contact sanders or wideband sanders with a contact shoe. For fine polishing beechwood, both white corundum and silicon carbide papers are suitable. For the very final round of finest polishing, sanding paper with a 180 grit normally is sufficient. Please observe the specifications of the respective stain producer.
Before staining, all the dust has to be thoroughly removed from the wooden surfaces. This holds especially true in series production on assembly lines. Today, dedusting is effected by brushing machines working with a strong air suction system, often in addition even with compressed air.
Once the wooden surface is clean, the stain can be applied. When staining wood, one normally works with an excess of staining solution. The wood is liberally „offered“ the staining solution and, given some time to take it in, the solution in excess is removed. In private use, normally a paint-brush and sponge are employed.
For commercial and industrial use, there are many techniques of applying stain, for example spray-painting with a spraygun or a spraying machine, roller application or the dip or immersion coating. Generally, the stains have to be adapted to the respective application method in order to achieve best results.
More information on this is available from the stain producers.
After staining, the wooden work piece has to dry. The stained wooden pieces dry at normal temperatures in a ventilated room within about 1 to 3 hours. The drying times can be significantly reduced to sometimes less than
5 minutes by using hot air channels.
The stained wooden surface has to be protected in any case by a coat of varnish or glazing. The varnish has to harmonize with the used stain. Stain producers usually offer suitable varnishes as well.
Depending on the technique applied, the colour tone will change once more with varnishing. Varnish always consists of a volatile thinner and non volatile ingredients. Bonding agents, coating agents, pigments, fillers and solid components of additives are counted among the non volatile components.
Today, many varnishes are water-based, that is they use water as a solvent.
Of course, a varnishing coat can also be applied to a non stained wooden surface, in order to keep the natural colour of the wood. In this case, just like with staining, the wooden surface has to be thoroughly cleaned as well.
For being able to stain wood, the surface has to be sanded beforehand. Many books have alredy been written about this topic. Many problems with staining can be reduced to a poor preparation of the wooden surface.
In the following, a few basic steps are summed up:
Using oil for surface treatment results in surfaces that are less smooth compared to a lacquer finish. However, it is precisely oils that strongly accentuate the vibrancy of the wood colour. Oiling wood has become very popular again in recent years. Oiled wood surfaces are especially preferred by purists. The surface treatment with oil hardly curtails the breathing ability of the wood. Thus, it is still able to absorb atmospheric moisture and contaminants and give them off again later in a regulated way helping to provide thereby for a balanced indoor climate. Before applying oils on stained surfaces, it is absolutely neccessary to consult the manufacturer about the suitability of the materials used.
Oiled surfaces are generally only slated for low duty use and wear. It is only with hard or flooring oils, as they are called, that a more resistant wooden surface can be achieved, so that these are also suitable for kitchen counters.
Handling is easy. The oil is applied several times and penetrates the wood. Excess oil has to be wiped off each time with a cloth. With the help of polish, a silky brilliant, water-repellent and durable surface is produced.
Waxing is an old technique for protection and decoration used indoors, which is rated very positively by construction biologists for keeping the originality and breathing ability of the wood. Wax-treated wooden surfaces captivate with their extraordinary, lustrous appearance. Wood waxes are offered as solid compounds or pasty balms. They consist of bees and vegetable waxes that may be partially combined with vegetable oils and resins. Waxed surfaces possess a light to average durability and are therefore not suitable for all areas of application.
As with oiling, before using wax on stained surfaces, the compatibility of the products should be confirmed by the manufacturer. A good alternative is offered by wax stains, for ex. the wax stains known as Becker-Acroma-ARTIWAX made from synthetic waxes, which are suitable for many applications.
Excerpts from "ARTI Holzbeizen“ with the friendly permission of Becker Acroma ARTI GmbH.