Can I use synthetic wood stains for the furniture? Should I stain with water-soluble dyes or synthetic wood stains? Can I use waxy stains? Synthetic wood stain is a frequent word in the mails I receive. And the answer is always the same: on antique furniture you should NOT use synthetic wood stains.
The “old” varnishes for wood
The first synthetic varnishes had the feature of forming a film on the surface. The film is nothing but a thickness that the varnish forms on the wood. This thickness has the function of isolating wood and reflecting the light. The big problem with old varnishes, such as flatting, is that if exposed to the sun and the weather is “flips”, that is, the film lifts off. The owners of the terraced houses have been well aware of the fact that in the last twenty years they had to varnish and varnish again all doors and windows. Synthetic wood stains have been invented to solve this problem.
What is synthetic wood stain?
Wood stains are synthetic varnishes that can be water-soluble or solvent-soluble. Solvent formulations are being abandoned in order to produce the first ones. Water-based products are easier to use and fall into environmental compliance standards. Although we must always be clear that we are talking about synthetic and non-natural products. The synthetic wood stain does not form a film on the surface but penetrate the wood pore by isolating it. Consequently, the staining agents do not lift off. When used in inner parts, they do not need final protection. If we use them outdoors, it is better to give a protection. We protect the surface with transparent, glossy, satin or opaque varnishes according to taste.
Water-soluble dyes or synthetic wood stains?
People often ask me if it is better to use a water-soluble dye of a synthetic wood stain. They are not synonymous and indicate two very different products. Water-soluble dyes are used to stain the wood. It is a highly resistant natural colorant that does not alter over time. They stain wood fibbers of the furniture and we use it before French polish. In this article you can find the recipe to prepare the dyes. Synthetic wood stains are solutions used to varnish the wood. Some wood stain are coloured. Colours are often the same of classic wood but you can also give the colour you like.
Why not synthetic wood stains should be used on antique furniture?
Synthetic wood stains, though not forming a film on the wood, penetrates the pores and drowns them in a synthetic substance that does not allow the wood to “communicate” with the outside. The wood remains as mummified; we can safely say that the wood treated with an synthetic wood stains is a dead wood. This does not interest us in an external door, a dome or tool garden cabinet. it is to be avoided on antique furniture. Wood of antique furniture is alive and needs to “breathe” by moving and adapting to the room environment. From my experience, and by my teachers’ experience, that furniture varnished with natural products break down less than those painted with synthetic varnishes.
Which varnish has to be used?
The only varnish I recommend for antique furniture is the shellac varnish. The shellac is a natural resin which is dissolved in alcohol to obtain a good varnish that has been used since 700s. It is often thought that French polish is a very glossy finishing but this is not always true. A good restorer can “tune” how to polish the furniture to get the desired gloss. We can also make a matte wax finish by giving the first coat by using a brush and after sanding the raised fibbers, applying a good wax. In this article you will find all the steps to get a good French polish with shellac. Find all the steps to carry out an excellent restoration of the antique furniture on Restoration of antique furniture: a step by step guide.