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 modern 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 ex-tensively 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.
Types of Brushes
Paint brushes are made in various shapes and sizes for different purposes. Those used in the course of general decorating work can be classified as follows:
Ground or Pound Brushes: These are intended for the application of oil paints, especially on large surfaces. The numbers on them indicate the approximate weight, in ounces, of the bristle employed. The sizes range from 1 to 8, No. 4 being probably the most useful for general purposes.
Ground brushes are round or elliptical in form and are bound with cord, wire, or metal .
The string-bound brush, though still employed to a very limited extent by the more conservative, has been superseded by the wire-tied or metal-ferruled variety. It may be observed, however, that ground brushes as a class are now comparatively seldom used. Their disadvantages are that they are somewhat heavy to wield, require a considerable amount of breaking-in, and have only a limited spread.
Nevertheless, in the opinion of many experienced painters, they are superior for many kinds of work to the modern flat brush which has largely taken their place; they are almost certainly better for the application of oil paint (which must be well brushed out), in contra-distinction to the high-gloss or enamel-type paint, which requires less manipulation and is flowed, rather than brushed, on.
New round brushes, such as pound brushes or sash tools, should always be wrapped before using. This ‘ bridling ‘ may be done with twine or cord as follows: Holding the brush in the left hand, handle outward, take about 5 ft. of strong, stout cord, and about 9 in. from one end make a small loop (not a knot), which is held by the thumb against the side of the brush just where the ferrule touches the bristles. The short end of the cord is held in place by drawing it slightly into the end of the brush. The long end of the cord is wound around the brush, care being taken that the successive turns make a smooth, solid coil. When the coil is wide enough draw the loose ends of the cord, resting in the brush end, back through the loop that was held under the thumb. Draw the under part of the cord snug downward and the outer part snug upward. That holds the coil firmly in place on the side. Now take the other end of the cord, and on the side of the brush opposite the loop made at starting make another loop by turning the cord backwards and taking one turn around the brush. Draw the free end through the loop, pull it snug, then tuck under one or two turns of the coil and bring it up towards the handle. The two free ends of the cord may now be joined and knotted firmly around the handle; or, better still, two tacks may be put into the shoulder of the brush and the cord ends may be neatly fastened to these. The bridle on a new brush may be drawn tight and loosened up afterwards if thought necessary.
In breaking-in round brushes, the aim should be to secure an even bevel on each of the two opposite sides of the brush. Otherwise the brush will wear to a point and be an inefficient tool. Avoid poking if possible, as it tends to make a brush stubby, spoils the bevel, and causes the bristles to cross.
Sash Tools: This name is given to the smaller-size brushes and originates from the fact that they are commonly used for ‘ cutting-in ‘ the sash or glazing bars of windows. As with ground brushes, the round or oval form has been, to a great extent, displaced by the small flat varnish brush, but it is none the less an excellent tool.
Varnish Brushes: Here again, the older rounded or oval types have given way to the flat variety, which are made in three thicknesses and in widths ranging from in. to 4 in. Since they are not intended for rough work, which would have the effect of breaking them in, they are mostly made with bevelled edges.
Distemper Brushes: We come now to distemper brushes, which are of equal importance to ordinary paint brushes in the execution of decorative work. These are made in a variety of patterns, and it is somewhat remarkable to observe how the popularity of particular forms of brushes varies in different parts of the country – in fact one might say in different parts of the world. In Holland the painter’s brush presents an appearance which the English can but consider as grotesque. They are very rough in appearance and apparently badly made; yet the Dutch painter is, as a whole, a first-class craftsman, and by means of such brushes can produce excellent work.
In is shown what is known as a two-knot distemper brush. In the South of England this brush is very much in demand. For larger surfaces a three-knot brus, is often used. In some places another form is preferred, viz. a brush which is not divided up into knots, but has the bristles distributed equally.
In most cases the bristles are kept in position by wire ties or by copper bands. Another form of a long bristle brush is known as a Kalsomine distemper brush. ‘ Kalsomine,’ or ‘ Calcimine,’ is the American term for distemper, and this brush is almost universally used in the United States. The nailed-stock distemper brush is used principally in the North of England. The question of the size of a brush is one which requires a considerable amount of thought and study. At first sight it may appear advisable that a man use only large brushes, particularly on distempered work, so that he may get over the work very quickly, but as a matter of fact the actual labour is intensified in almost an exact proportion to the size of the brush, and it will be found most economical to have moderate-size brushes in most cases. The exact shape is largely a matter of personal prejudice.
Fitches: For fine decorative work on a small scale, such as picking out enrichments or painting mouldings, round or flat hog-hair tools, up to about 1 in. in width, called fitches, are made. A thin, flat type, with the bristles set at an angle, is employed for lining and usually known as a ‘ lining fitch.’
Stipplers are made in a variety of shapes. Stipplers are, of course, used on both distemper and oil-painted work, to produce a comparatively rough surface so as to eliminate excessive gloss and produce a pleasant soft effect. While the paint or distemper is wet the face of the stippler is applied with some force. This breaks up the level surface into minute hills and valleys, so to speak, and thus produces the softened effect. Stipplers are very expensive, so that care must be taken with them in order that they retain their good quality; they must be thoroughly cleaned after use, and kept wrapped up in wax paper or a piece of American cloth. They should not be kept in a very dry place in case the backs crack, and on no account should they be placed on the bristles, because this would cause the bristles to bend out of shape and render the tool practically useless.
Treatment of New Paint Brushes
When brushes are new they are not at their best; in some cases, especially with cheap tools, there may be loose hairs and dust present. By rolling the brush handle between the hands with the bristles-end down, much of this dust can be shaken out, and the loose hairs which then stick out from the brush can readily be removed. Then the brush can be roughly curried by passing the bristles across the edge of a dull knife held tightly against the bristles as they are squeezed through the hand. Whatever precautions are taken to clean new brushes, it is always best to break them in on outside work before attempting to use them on varnish or enamel work, as the presence even of a small amount of dust or loose hair will spoil such work. Before using a new round pound brush, or any brush in which the tightness of the bristles in the binding depends on the tightness of the handle, it is a good practice to part the bristles, pour a little water into the throat of the brush, and let it stand for an hour or two brush-end up. This method is to be preferred to the practice of setting the brushes in a tub of water. Only enough moisture is required to bring the handle back to normal size, and a prolonged soaking is likely to swell the handle enough to affect its lasting qualities.
Care of Brushes
Good-quality paint brushes are expensive tools, and if they are not kept clean and in good condition will not apply paint properly.
Ideally, all brushes should be cleaned immediately after use. The best way of doing this is first to remove as much paint as possible by means of a stick or some similar device which will not injure the bristles, and then clean them with turpentine or white spirit and wash them in slightly soapy water. Take care to get rid of all paint not only from the tips of the bristles but from the heel of the brush as well. After washing, they should be carefully dried and kept in a moderately warm place where there is good air circulation. Mildew tends to form on bristle which is damp and stored in a poorly ventilated place.
In practice, when a brush is only put aside for a time, or overnight, and is to be used to apply the same material again, thorough cleaning is seldom carried out and, instead, the paint brush is usually suspended in water which prevents the paint in it from hardening. The brush should never be left standing on its bristles in a pot of colour, even for a short period, as this destroys their shape and makes the tool useless. It must be suspended so that the tips of the bristles do not come into contact with the base of the container. This can be done by boring a hole through the handle of the brush and passing a stout wire through it, the wire being so fixed across the top of the container that the bristles are kept clear of the bottom. There are various forms of ready-made brush suspenders, or brush ‘ keepers,’ designed for this purpose, and their use is recommended.
There is some difference of opinion as to the advisability of suspending brushes in water. Those who condemn the practice maintain that the water makes the bristles soft and flabby; this may be the case when a new brush is wetted in this way, but after it has been used the paint in it serves as a protection. Probably the water causes little or no harm provided the brush is kept in it for a limited time only, as, for example, overnight. It is certainly better to use linseed oil instead of water, but the latter is cheaper and more readily available. Turpentine should never be employed, as it tends to make the bristles stiff. Brushes which have been used to apply some of the new forms of paint, such as the synthetic resin variety, should not, however, be suspended in oil, but should be cleaned with the thinner recommended for the paint in question, washed, dried, and laid on a flat surface.
It is good practice after cleaning a brush to comb out the bristle; if the tool is not likely to be used for some time, wrap it in grease-proof paper before putting it away, and lay it flat in a dry place. Bristle is liable to be attacked by moth, so that some kind of moth repellant should be kept in any drawer or container in which the brush is stored.
If string-bound brushes are kept in water for a time, the water should not come up to the binding.
Varnish brushes should never be placed in water but, if not cleaned, should be suspended in linseed oil – or a mixture of about two-thirds oil and one-third turpentine. Before using a varnish brush treated in this way, care should be taken to wash out the oil from the bristles by means of solvent.
Paint or varnish brushes, the bristles of which have been allowed to get hard through lack of care, can often be restored to service by the use of one of the various proprietary brush renovators. Some of these, however, contain strong alkalis which are injurious to the bristle if too strong a solution is employed, and may also attack the setting of a cheap brush if the cement is not proof against alkali. A good quality non-caustic type of paint remover is probably safer to use for the purpose, though here again, unless the cement is resistant to the action of strong solvents, it may be affected.
Distemper brushes should be washed thoroughly clean, after the day’s work, with a mild neutral soap, rinsed well, as much surplus water as possible expelled by vigorous shaking, and the brush hung up, bristle downwards, to dry. It should never be kept suspended in water and should be thoroughly dry before it is used again. A damp distemper brush has no life in it.
Fitches and writers’ sables should be well rinsed with turpentine or white spirit after use, special care being taken to see that all paint is removed from the heel. When dry, tallow should be worked into the hairs which should be drawn to a fine point between the fingers, to maintain the shape of the brush. Before being used again, the tallow should be removed by means of turpentine or other suitable solvent.
To remove any kind of painting material from a brush, a good general rule is to employ for the purpose the thinner recommended for the material in question. Thus, for oil paint, use turpentine or white spirit; for distemper, use water; for knotting, use methylated spirit; for brushing cellulose, use cellulose thinner.