Brushes
It seldom pays to buy cheap tools, but with no item is this more true than with paint brushes.
With the exception of those for specialist use, such as sign writing, they are supplied by the employer, and because many
, operatives fail to keep them clean and in good condition, and generally misuse them, there is some temptation to purchase them on price alone.
It may be said at once that not only will low-grade brushes soon wear out, but also that it is quite impossible to get good results with them.
The price of first-class brushes has risen steeply since the end of the first World War because of the growing scarcity of hog-bristle, for which, in the making of paint brushes, there was, until
recently, no equally good substitute.
Pigs are, of course, bred mainly for food and, under modem conditions, are slaughtered young before their bristles have had time to grow long enough for paint-brush purposes.
Until the early part of the twentieth century, Russia and Poland provided the bulk of the world's supply and China and India most of the remainder. But following the 1914-18 war, the pig-breeding industry in Russia was reorganised and as a result, although the strains were improved, available bristles became shorter.
In China and, to some extent, in India, the pig still runs wild and is allowed to develop longer bristles, and these countries are now the main source of supply of natural bristle.
The latter has two features which make it ideal for the application of paint: it tapers from top to bottom, which gives it the essential combination, for the purpose, of stiffness and elasticity, and it has a split end or " flag" which enables it the better to pick up and spread the paint.
Its surface is marked by a series of minute serrations which, in the process of brush-making, helps to make sorting easier.
It is highly improbable that the supply of natural bristle available for paint brushes will ever again be as great as it was, and it is extremely likely that it will continue to decrease.
A great deal of research has been carried out, especially in the U.S.A., to produce a synthetic bristle with similar characteristics to those of the natural article and after much experiment these efforts have met with success.
It can now be stated with assurance that these nylon or synthetic resin brushes have passed the experimental stage and, in the opinion of most men who have used them, are, if made by a reliable firm, fully as good as, if not actually better than, a high-grade natural-bristle brush.
It is true that they are more expensive than the latter, but experience has shown that they wear considerably longer and keep their shape better in actual service.
To satisfy the demand for cheaper brushes, horse hair and fibre are extensively employed: they lack the resiliency of bristle, do not taper, and have no "flags": in consequence, they neither hold nor spread the paint so efficiently and are much inferior.
In horse-hair, the ridges or serrations are much less marked, while in fibre there are none.
In some grades of paint brushes bristle is blended with varying proportions of horse hair or fibre.
The words" All Bristle" stamped on a brush are usually-though not, unfortunately, invariably a safeguard that the pig bristles have not been adulterated.
The bristles (using the term loosely to include horse hair, fibre, etc.) are held in place by means of suitable cement and are secured to the handle by string or, more commonly nowadays, by metal bindings or ferrules.
In years gone by the cement was composed of materials such as glue or rosin, but to-day in good-grade brushes, these have given place to vulcanised rubber and other special compounds which are not affected by the various solvents used in modern finishes and are also proof against acids, alkalis, and other potentially injurious substances.