Cyclopedia of Painting

Front matter

|Cyclopedia of Painting | Containing Useful and Valuable Information on the Following Subjects

|Adulteration of Paint—Blistering of Paint—Brushes—Calcimining—Carriage Painting—China Painting—Colors—Color Harmony—Color Mixing—Color Testing—Exterior Painting—Gilding—Graining—House Painting—Marbling—Mildew—Oils and Driers—Oil Painting on Glass—Painting a Bath Tub—Painting in Distemper—Paperhanger's Tools—Paperhanging—Pigments—Plain Oil Painting—Primary Colors—Priming—Scenic Painting—Sign Painting—Stains—Staining—Stencilling—Turpentine—Varnishes—Varnishing—Water Color Painting—When Not to Paint—Practical Points on Painting—Useful Information | BY | GEORGE D. ARMSTRONG | | CHICAGO FREDERICK J. DRAKE & CO., PUBLISHERS 1908

Copyright, 1906. By Frederick J. Drake & Co.

Introduction

INTRODUCTION.

The character of this work is indicated by its title. The topics are treated with a view to technically instruct those who desire to make a study of the art of painting as practised in the paint-shops of this country.

Every effort has been made to ensure accuracy in all the statements made. The employment of engravings, wherever it was necessary to more fully explain the text, will be found to add greatly to the value of the work, while the many extended articles will, it is believed, be interesting even to those who read only for information on general topics.

The book is one easy of consultation, virtually a Cyclopedia, and readily distinguishable from a collection of scientific treatises.

The Author.

Adulteration of Paint

CYCLOPEDIA OF PAINTING.

ADULTERATION OF PAINT.

To understand this subject intelligently it will be necessary to possess some slight knowledge of chemistry and of the materials used by chemists, but any intelligent person can, by careful reading of these descriptions, test substances qualitatively without the aid of expensive apparatus or external assistance of any kind. For quantitative analysis a delicate chemical balance will, of course, be required. Take paints first. White lead is now very seldom sold in the dry state, but samples are occasionally met with. Its covering power being superior to that of any other known paint, it is very largely used, and it is frequently adulterated with substances of inferior quality. The most common adulterants are sulphate of baryta and chalk.

Sulphate of Baryta. Treat a small quantity with dilute nitric acid, and heat on the sandbath. If any insoluble remains, it is either sulphate of baryta or insoluble silicates. Filter, take a portion of the insoluble on a piece of clean platinum wire moistened with hydrochloric acid, and test at the blowpipe. If the flame be colored green, the precipitate is sulphate of baryta. By moistening the wire in hydrochloric acid the green color is reproduced many times.

Insoluble Silicates. If no green color appears, the insoluble is a silicate. This may be proved by forming a bead with microcosmic salt on a loop at the end of the platinum wire, and taking some of the precipitate on this bead, fusing it again in the blowpipe flame. If small infusible particles whirl around within the bead while in the flame, the presence of silicates in the precipitate may be inferred.

Chalk. The presence of chalk can only be ascertained after separating the lead. This is best done by adding ammonia solution to the nitric acid solution until alkaline, then sulphate of ammonia in excess, and boiling for five minutes. Filter off the black precipitate which is formed, and to the filtrate, first tested with an additional drop or two of sulphate of ammonia to insure the removal of the whole of the lead, add ammoniac oxalate. If a white precipitate appear, it is calcic oxalate. Test a portion of this precipitate at the blowpipe. A brick-red color imparted to the flame verifies the presence of chalk.

White Lead. The presence of lead should be ascertained. This is indicated by the black precipitate given with sulphate of ammonia. It may be best ascertained by boiling the nitric acid solution to expel the free nitric acid, adding dilute sulphuric acid to the clear solution, dissolving the white precipitate of sulphate of lead thus formed in ammoniac acetate, and adding potassic chromate to this solution. A heavy yellow precipitate (chromate of lead) forms when lead is present.

Sulphate of Baryta and Silicates. Take 20 grains of the sample, treat with dilute nitric acid as before. The quantity taken for analysis may be weighed in a watch-glass or a small basin, but should be transferred to a beaker, and the glass or basin washed with distilled water before the acid is added. If this precaution be not taken, and the acid added directly in the watch-glass or basin, to be washed into the beaker afterwards, the violent effervescence which takes place on the addition of the acid will occasion considerable loss by spurting. If, after heating with nitric acid, an insoluble remains, a few crystals of chlorate of potash may be added to the boiling liquid to insure the solution of all soluble substances. The boiling is continued for a few minutes, then cold water is added, and the whole passed through a filter. The insoluble on the filter is washed with hot water until the water leaving the filter is no longer acid to litmus paper. It is then dried on the water-bath, ignited, and weighed. Test at blowpipe as before. Sulphate of baryta and silicates, if both present, are not usually separated.

Weighing Precipitates. This general direction applies to almost all precipitates. If strong acids or acid and chlorate of potash are used, the liquid should invariably be diluted before filtering. In washing, allow the whole of the wash water to drop from the filter before adding more water. When thoroughly washed, fold the filter paper flat in the funnel, or, better, transfer the filter paper and its contents to a large watch-glass or flat basin, and dry on a water-bath. When dry, carefully unfold the filter over a quarto sheet of stiff glazed paper, with a feather brush off every particle of the precipitate adhering to the filter paper, collect the precipitate on the glazed paper, again using the feather, and cover over the precipitate with the funnel. Fold the filter paper till it assumes the appearance of a solid cylinder about one inch in length, and ignite with the Bunsen burner over a weighed platinum or porcelain capsule. After a while the filter paper becomes a charred mass of smaller dimensions, and drops from the wire into the capsule. The wire is cleaned into the capsule, by means of the feather, of any adhering particles, the charred paper is crushed with a glass rod, and ignited over a Bunsen until the ash is no longer black. The capsule is then stood on a porcelain slab, and the precipitate carefully transferred from a glazed paper into the capsule, the feather being employed to remove the last traces. The capsule is then ignited over an Argand burner until the weight is constant. The filter paper must always be ignited before the bulk of the precipitate is transferred to the capsule.

White Lead. The nitric acid solution obtained as before is boiled nearly to dryness, and if a precipitate forms a little water is added, then dilute sulphuric acid in small quantity, and the boiling continued for some minutes to expel the last trace of nitric acid. An excess of sulphuric acid is then added to precipitate the whole of the lead and lime as sulphates, which appear as a white heavy powder. The beaker and its contents are then cooled by immersion in cold water. When cool, double the bulk of alcohol is added, and the whole allowed to stand for some time—over night if possible. It is then filtered and washed with alcohol until the washings are no longer acid, dried, ignited in a porcelain capsule, and weighed as above. From the weight obtained deduct .05 grain, the amount of ash contained in an ordinary Swedish filter paper, the remainder multiplied by five for the percentage of sulphate of lead, and (if chalk is present) this again by .852 for the percentage of white lead. If the sample contains chalk, the percentage of white lead must not be estimated until the percentage of chalk is determined. The percentage of chalk is converted into its equivalent of sulphate of lime. This latter deducted from the percentage of sulphates of lead and lime, and the remainder multiplied by .825 for the percentage of white lead.

Chalk. The readiest way to estimate chalk is to divide the nitric acid solution obtained above into two equal parts, in one estimate the lead as above (multiplying the weight found by ten instead of five), and in the other estimate the chalk. The lead is removed with ammoniac sulphide in the manner described before, to the clear filtrate, ammoniac oxalate is added, if chalk is present, a white precipitate of calcic oxalate is produced. This precipitate is assisted in its separation by boiling. Then collected on a filter, washed with hot water, dried and weighed. The ignition is complete when the contents of the capsule assume a tinge of gray color. The weight obtained after deducting .05 grain of filter ash is multiplied by ten for the percentage of chalk. In inexperienced hands it will be better to ignite strongly and weigh as lime, multiplying by ten for percentage of lime and by 1.7857 for percentage of chalk. This chalk may be converted into sulphate of lime by multiplying by 1.36, and the product deducted from the percentage of lead and lime obtained above, prior to calculating the percentage of white lead. The chalk precipitate should be tested at the blow-pipe for its characteristic brick-red flame. Some analysts treat the mixed precipitate of sulphate of lead and calcium with concentrated solution of ammoniac acetate, and weigh the insoluble as chalk. This method is unreliable. The oil must first be burnt off, and the ignition continued until no black carbonaceous matter remains. It must be ignited in a porcelain basin over an Argand burner, turned low at first and gradually raised. The ignition must be completed over a Bunsen. Much time is saved and the analysis rendered more accurate by spreading the mixed paint in a thin layer over the bottom of the basin, and when the ignition is nearly complete, by crushing the scaly crust with a glass rod, carefully remove the adhering pieces on the glass rod by means of a feather. The difference in weight before and after ignition represents the oil plus loss by reductions of white lead to metallic lead. The residue is washed into a beaker with water as before, and afterwards with nitric acid. The metallic lead, which adheres strongly to the bottom of the basin, must be rubbed vigorously with the end of a glass rod until entirely removed. This requires a little patience, but it yields to persistent rubbing. The remainder of the process is the same as in the case of dry white lead.

Blistering of Paint

BLISTERING OF PAINT.

In the following lines are laid down some general rules that govern this phenomenon, and from the same draw some practical conclusions, the object of which will be to set the question at rest. The blistering of paint is in a large measure traceable to the position of the surface, it is usually found on work presenting a south aspect, or exposed to the full rays of the sun. As a defect it is associated with the summer season, winters being opposed to its action. The deduction to be drawn from this is that it is the effect of heat. Paint is a body both mineral and metallic, made into a plastic condition by oil, the object of which is to keep out the moisture from exposed surfaces in buildings, and to offer on internal work a uniform and pleasing surface to the eye. The oil used is linseed, which by boiling attains setting or drying qualities and becomes better by keeping, its thick or heavy nature when loaded with mineral and metallic matters being reduced for working purposes by spirits of turpentine, a volatile spirit that is a mere aid to the spreading of paint. Paint so largely composed of oil will never fairly set or assume a dry state. However dry and brittle if: may appear, it is capable of being rendered soft and plastic by the application of heat, and hence the hand stove of the painters is the most ordinary instrument for the removal of old paint. We mention this, for it is clear that, approach the subject as we will, we find heat the prime cause of the blistering of paint. Closing in with the subject, and bringing it into narrower lines, blistering, properly speaking, is wholly confined to wood as a base or groundwork. It is true it is not unknown to iron or plaster, but in these cases it is variant in form, and not blistering in the true sense of the term. The blistering of paint on iron is not traceable to the softening of the paint, and the shelling up of the same, but to water making its way to the naked iron through some crack or defect in the paint, and becoming an active agent in oxidization. The blister thus forced is clearly the separation of the film of paint from the iron by the formation of rust upon the face, which, as a foreign material, forms an effectual separation of the two bodies. The extension of these blisters is dependent upon the supply of water, and, unlike the true blister, is not dependent upon heat or a south or sunny aspect. The blistering of paint on iron occurs in any aspect or position, in the full light or in the dark,

in the summer or the winter, the destructive agent being water, it is dependent upon no other conditions. The blistering of paint upon plaster is in a large degree analogous to that of iron, inasmuch as it is formed by the disintegration of the base by the action of water. Painted plaster-work, so long as water can be kept from percolating through the cracks or faults, or gaining entrance from above by filtration, or from below by capillary action, is a highly durable material, but the moment water gains a footing the lime in some degree is dissolved, and, upon being removed and redeposited, undergoes the process of recrystallization, a powdery substance is thus formed that comes as a stranger between the paint and the plaster, in which respect it bears a strong resemblance to rust, the result of the oxidization of iron. Large faces of plaster are subject to fractures from expansion under the heat of the sun, or from the lifting the upper members of a building, consequent upon the admission of water from gutters or copings, the lifting being the result of secondary crystallization set up in the joints of mortar. This is an explanation of the fact that the blistering of paint always occurs in the neighborhood of cracks or fractures in the plaster, and is more pronounced in the cornice or upper part than in any other part of a building. In proof of its being the result of crystallization, the face of the plaster is always found to be covered over with powdered lime. The painter, finding this, takes care to saturate the disintegrated face of the framework in effecting repairs, but this, as he finds to his chagrin, is no protection against a recurrence of the evil, for so long as water or moisture is admitted at any point, so long will this abnormal blistering ensue. The blistering of paint upon plaster work, like that upon iron, is not dependent upon heat, it is a chemical action set up by water upon a body of dry lime in a partial state of crystallization, it is caused by the lime dissolving, and its removal—it may be but in an infinitesimal degree—and its recrystallization. Upon the water evaporating, the result is a dry powder that works an effectual separation between the film of paint and the ground-work of plaster, and it does not attach itself to either of the bodies, but remains a powder until the film of paint or blister is removed, when it may be dusted off with a brush. The blistering of paint upon wood is distinct in its order, and is the general blister known in the trade. It occurs on the face of woodwork exposed to the sun, and is traceable to the influence of heat. It is not pronounced in the case of new work, where the body of paint is not great; but it is a great evil and an eyesore on old work, where the coats of paint are layered one on the other. Wood, as a groundwork, is a porous body highly charged with moisture in a natural state, and never free from it in a so-called dry state when used in exposed situations. It may be taken that wood, during the winter season, or one-half of the year, is absorbing moisture. This is seen in outer doors, gates, sliding sashes, and shutters, as the carpenter is constantly being called into requisition to ease the same. This moisture, so largely present in the atmosphere, cannot be kept out of the wood by the most careful painting. In store fronts it has ready access to the back of the woodwork, the face sides being the only ones which are painted, in doors and gates it is absorbed from the sills or the ground, from the fact that the lower edges are unpainted. There is always some portion of the woodwork hidden from the eye which is unpainted, and there the system of absorption is active during the winter or rainy season. Wood in this state during the hottest days in summer will make efforts to throw off this moisture. Then the heat of the sun is applied with great force to the painted face, and the unpainted face is in the cold shade. The effect of this powerful heat is to draw the moisture to the face of the wood, where its course is arrested by the sundry impervious coats of paint, it is here generated into steam, the expansive power of which forces away the paint, and the familiar blister is formed. Paint, as a mineral or metallic body, does not incorporate with the wood, it simply adheres thereto, forcing its fronds, so to speak, in the pores of the wood, and filling up the interstices formed by the bundles of fibers. Hence we find that paint fails to adhere to highly resinous or greasy woods, and the knots themselves, from being hard and compact, must be faced with knotting composition as a ground for the paint.

Brushes

BRUSHES.

Cheap goods of any kind never reflect credit on the maker. Neither do they give satisfaction to the consumer or dealer. It requires skill and art as well as quality of material to produce high grades of goods, and such must always bring their price and never fail to give satisfaction. For this reason, the intelligent, practical and thoughtful workman will always look for the best tools. Good bristle brushes cannot be made of any substitute for imported bristles, and cheaper grades are always produced by adulteration and mixtures. The cheapening of goods is generally done so that

it shows least to the eye, in the center of the brush, and covered by good quality to make the goods as marketable as possible. Such goods cannot be expected to be durable or give satisfaction.

First-class goods can also be ruined or lose half their value if they are not properly cared for. Paint and varnish, as well as calcimine and whitewash brushes, should never be allowed to stand on the ends of bristles over night, but should always be cleaned thoroughly before quitting work, and care hung up, paint and varnish brushes in oil or varnish, and calcimine and whitewash to dry. It will injure any brush to let it remain in water. Should paint, varnish, leather-bound whitewash or wall brush be found that has become loose from shrinkage, take a tablespoonful or so of water, open the brush and pour the water into the center. This will swell the parts and make the brush as firm as when first made.

New brushes when first put in work are apt to shed any loose bristles that have not been fastened when made, and while such loose bristles are always cleaned out before the goods are put up for market, not all such loose bristles or hair can be cleaned out, and such are sure to come loose when the brush is first used. This defect will cure itself in one day's use.

Do not condemn the maker if one brush is brought back by a practical workman, who possibly has had one or more brushes out of the same dozen that were all right and gave perfect satisfaction, but look for the cause or defect in the user. Remember that goods are made up in large quantities, and when the bristle is prepared it is in large batches. It must naturally follow that if one brush, or one dozen, or any quantity of such a lot is good that all must be, or if one is bad all must be so.

The greatest annoyance that manufacturers have to contend with is the improper or careless use and care of good, first-class brushes.

Good goods of all kinds are a credit to the manufacturer, give satisfaction to the mechanic in use, and pleasure and profit to the dealer to sell. They are sure to bring their own reward.

Brushes are made of bristles and of hair, bound to a handle by cord, wire, metal stamped to imitate wire, tin, copper and brass. The oval and round paint and varnish brushes are generally bound with cord, wire or its imitations, and copper and brass. The flat bristle, fitch, badger, bear and camel's-hair brushes with tin. The ordinary paint brushes contain the inferior or coarser grades of bristles, the varnish brushes are selected or finer qualities. The oval and round brushes are numbered by the brush-maker to designate sizes, from No. 6 down to No. 1. thence from one to 000000. For carriage painting the sizes between one and four naughts are considered best, the smaller ones may be used, but it is advantageous to use as large a brush as possible on most of the work. Small brushes called tools are numbered from 1 up to 10, the latter being the largest. Brushes are generally used in sets, as, for example, in painting a body or gear, a large brush for laying the paint would be used, and a small tool for cleaning up around the moldings, nuts and bolt-heads. It would be an almost endless task to illustrate and describe all of the many varieties of paint and varnish brushes, and a few of the principal ones only will receive attention here. Russia is the great bristle growing country, and her exports reach as high as 5,000 tons of this commodity every year. Hogs in countless herds roam the deep Muscovite forests, where the oak, the pine, the beech, larch and other nut bearing trees cover the ground with acorns and nuts to the depth of a foot or more. But these swine are not all of value for their bristles. The perfect bristle is found only on a special race, and that race fattened in a certain way. On the frontiers of civilization all over the Muscovite territory are the government tallow factories, where animals reared too far from the habitation of men to be consumed for human food are boiled down for the sake of their fat. The swine are fed on the refuse of these tallow factories at certain seasons, and become in prime condition after a few months' feeding. It is from these animals that the bristles of commerce mainly come. When the swine are fattened, and their bristles in fine color, they are driven in kraals so thickly that they can scarcely stand—irritated and goaded by the herdsmen till they are sullen with rage , striving, struggling and scrambling together in feverish rage, they are seized one by one, by the kak koffs, a class of laborers educated to plucking swine, and their bristles pulled out by the roots. The perspiration into which the poor creatures are thrown by their exercise causes their bristles to yield easily. The process is pleasant neither to the eye nor the ear. The hog strenuously resists with loud outcries, and vehement opposition. It does no good. Once seized, he is instantly divested of

his clothing and then immediately released, goes grunting off to the woods.

The so-called French bristles are principally from Russia stock, cleaned and bleached to render them white and exceedingly elastic, yet soft as an infant's hair. From these are made the fine pencils of the artist. Length, elasticity, firmness and color are elements that constitute their excellence, and the bristle expert can readily assort them for their special uses.

The ordinary paint brush for general work is made either from selected Russia bristles, or with an inferior gray center, inclosed by fine white bristles. Carriage and wagon painters usually select the best Russia bristles, and the size known as 0000 is used for rough-stuff and foundation coats, while the house painter would choose a larger one possibly. A new brush of this description will not work well unless bridled, that is having an extra binding added, and this may be done in several ways.

By winding a strong cord around the bristles to about the middle of the same, or, as far from the original binding as desired. By covering a portion of the bristles with leather stitched on tightly. By wrapping a piece of muslin around the brush, then tying a cord at the center of the bristles turn the muslin back and tie it securely to the handle. By using a patent metallic band or binder, and by other means, the object being to shorten the exposed bristles until the brush is partly worn down, when the extra binding may be removed.

Badger-Hair Varnish Brush. The badger-hair brush is next in importance. It is well bound in tin, hair set in glue, handle nicely japanned, and chisel-pointed. For varnishing small panels or parts of a body it has no equal. The best badger-hair is imported on the skin from Germany and Russia.

Camel's-Hair Brush. For laying fine color no better brush can be had than the camel's-hair brush, called by some mottlers, by others blenders, and again by others spalters, each term, however, is foreign to the American painter, and the camel's-hair brush is by far the most appropriate, and most commonly used. The hair used in these brushes, however, is not all taken from the camel, much of it being from the tail of the Russian brown squirrel. The hair is first cut from the tail with scissors, the wool or under fur combed out, and then tied in bunches ready to be straightened. This requires skill and practice. The hair is placed in metal cups having a thick, loaded bottom, and by quick motion of the hand, drummed on the bench for a considerable time, until the pointed or fine ends are all even with each other. In the process of cutting and cupping the lengths are kept separate as far as possible. The hair is now ready for the brush-maker, who cups and combs it out, weighs the quantity required, and places it into the ferrules or tin bands. It requires skill to handle the short, slippery hair and keep it in shape. It is not many years since work of this kind was all done abroad. Now, it is claimed by experts that the American manufacture of most kinds of brushes excels the foreign goods. The chiseled camel's-hair brush is something entirely new, and is certainly a very fine brush and well calculated to do smooth, particular work. Another class of these goods are made extra thick and from picked camel's-hair, the binding of brass having its edge turned under, which gives additional security to the hair and prevents cutting the hair on the edge of the binding, which too frequently happens.

Camel's-Hair Tool. Small brushes, called tools, made of camel's-hair are used for blacking irons, lacquering, and other work of like nature. The next brush to be considered is the camel's-hair duster, a tool used mostly by gilders in removing the loose gold leaf from their work when gilding. These are bound in split quill and fastened with wire. The next to claim attention is the gilder's camel's-hair tip. This is made by laying a thin layer between two pieces of card-board and gluing the whole firmly together; it is used to lift and carry to the work the pieces of gold leaf. A slight moisture or stickiness is given the hairs by simply passing them over the face or hair of the head, and then the gold leaf can be easily lifted from the cushion on which it has been cut and dexterously laid upon the gilding size.

For painting walls a large flat bristle brush is used, made of all white bristles, bound in copper, brass or galvanized iron. It has always been a difficult task to make a wall brush to stand the hard usage it generally receives, but now that machinery of the most approved pattern has been introduced in the brush factory these brushes are made under warranty.

Flat Bristle Varnish Brush. These are made of the best white bristles, set with glue, doubled nailed, soft yet very elastic, with chiseled points. They are considered the best brush made by many of the best varnishers. They are put up in sets from one inch in width to three inches. These brushes, if used with care, will wear a long time.

Flat Chiseled Brush. Flat paint brushes are preferred by some. These are chiseled or ground off on the sides to form a thin edge. They are bound in tin or rubber and are graded in size by their width.