|Two varieties of Shellac: Dewaxed Platina on left and Natural Golden on right|
India is the world's primary supplier of Shellac. The tropical jungles of eastern India (whatever little is left of them) continue to yield tons of laac smeared twigs that are processed into usable Shellac.
Shellac or laac (as it is known locally) has been around in India for centuries and has been used as an effective wood finish for as long. The use of Shellac in finishing travelled to the West following the arrival of European seafaring traders in the 16th and 17th century.
Today, most wood finishers seem to prefer the de-waxed, bleached variety of Shellac. Natural Shellac is golden, orange or garnet in colour and full of a type of wax.
De-waxed Shellac comes in many varieties differentiated chiefly by the extent of bleaching. Shellac from which wax has been removed is usually of a golden or garnet tint. This Shellac is then bleached to different extents, producing variants such as Platina, Blond and so on.
De-waxed Shellac is virtually colourless, dries very hard and adheres to virtually any surface. This variety is most widely used in the pharmaceutical industry to coat pills and capsules.
Many woodworkers claim this is the best type of Shellac for finishing. In India, however, woodworkers traditionally have always used, and continue to use, natural Shellac for finishing.
There are varieties or grades of natural Shellac as well, starting with seedlac, which is an unfiltered first stage of Shellac production where the bodies of the microscopic insects that produce laac are present. This Shellac is distinctly orange in colour and is the most widely available in Indian hardware shops.
The next type is called button laac; this variety has some of the wax and most impurities (dirt and dead insect bodies) removed and is pressed into large button like shapes.
The third variety is purified Shellac which still retains its natural wax. This comes in the form of fine flakes and in a variety of colours, including Lemon, Garnet and Golden.
I tested some natural Golden Shellac and loved it. The flakes dissolve quickly and easily in spirit (rectified alcohol) to form a dark cloudy finish. (see photograph).
|The two trays have been given a couple of coats of Shellac: the left is one finished with Natural Golden and the right one with Dewaxed Platina. In the foreground are pieces of the original Pine used in makig the trays.|
I tried some of it on a pine tray and was very pleased with the splendid golden colour that it imparted. The Platina de-waxed Shellac, on the other hand, did not tint the wood.
Clearly, the choice of Shellac depends on personal preferences but the notion that Shellac with wax is inappropriate for finishing is not correct. It would of course be a wrong choice if Shellac is being used as a sealer over which some other finish such as polyurethane is to be applied.
Natural Shellac dries as hard as the de-waxed type but is easier to use for French Polishing on account of the wax it contains. The use of de-waxed Shellac in French polishing requires the use of some kind of oil which needs to be removed later on. Natural Shellac does not require the use of any oil and the wax seems to bond well with the Shellac.
Traditional finishers in India, at one time, would add various resins such as rosin (Pine resin) gum Copal and Sandarac to add shine, hardness and so on to the Shellac polish. These techniques are mostly lost. But the use of the much cheaper "natural" Shellac varieties, some of which like Natural Lemon are extremely light, continues and has much to recommend itself.
24 March 2017