PAINT AND COLOUR MIXING

EVERY painter and decorator should be able to mix a paint to match any given colour, but perhaps not more than one journeyman in twenty is competent to do such work, owing to a lack of training. The following course of study is recommended to those who desire to master the subject of colour mixing, but it should be understood that the art is one which cannot be acquired in a day, but will require a great deal of perseverance to produce satisfactory results. Some people are deficient in the colour sense. In other words, they are partially colour-blind, and cannot distinguish certain colours from other colours. Such people can never make good colour-mixers. A very keen eye that can detect small differences in hue is necessary.

For the mixing, a flat non-absorbent surface, such as a sheet of glass, marble, or slate, is required, one or two spatulas, a series of different colours, which in this case may be in powdered form, a bottle of turpentine, and a bottle of raw linseed oil, preferably bleached, or refined, so that the oil may not change the colour of the admixtures. White will, of course, be required also; zinc oxide is the best pigment to use, because it is a purer white than white lead, and also because it has no adverse effect upon colours containing sulphur, such as cadmium yellow, ultramarine, and vermilion. Most painters are, however, more familiar with white lead.

Simple Experiments

We will take green by way of example. To produce it, mix together equal proportions of Prussian blue and chrome yellow, placing the powders side by side on the sheet of glass and adding a few drops of oil and turpentine, and then by means of the spatula mixing the blue and the yellow together. It will be found that this gives a dark bluish green, and at once we have learned the particular green produced by the admixture of Prussian blue and chrome yellow. We have also learned that Prussian blue is a very strong staining or tinting colour. The next thing to do is to take twice or three times as much chrome yellow as blue, mix together as before, and note the difference. A good plan is to paint the mixtures on a board and to mark a number against each, and in a little book record what each mixture consists of. This will be very useful for reference. Good-quality wallboard will answer well for painting on, as it is very light to handle. A third experiment will consist in adding a proportion of white to the green, and it will be found that this does not add to its beauty, but gives it a greyish tint, which is not pleasing. It is for this reason that greens are so frequently used exactly as they come from the makers.

Continuing the experiments, we next take a more brilliant yellow than the chrome, say bright middle cadmium yellow, and mix it with the Prussian blue; a rich green will result. Then we try sienna with the blue, and then sienna and chrome mixed, then the same two again, with the smallest touch of umber, or Vandyke brown, or both, painting out each one on the board, until we have a whole series of greens, and in the little book a record of how they were produced.

Having experimented with all the principal yellows and light browns, we next go back and, starting with chrome yellow again, try the effect of mixing blues other than Prussian blue. For example, we can use ultramarine, cobalt, and even indigo with the yellow. We can also add black to yellow, which will give a very dark sombre green, but one which is useful on occasion.

The same system of producing colours by the admixture of other colours can be followed in the case of reds, blues, yellows, browns, and even whites, the last named being capable of yielding a series of greys when mixed with black which are often in demand. In all these colours a greater or less proportion of white will usually be necessary.

A final experiment is to ascertain the colouring strength of different coloured pigments by adding different proportions of white. These should be painted out on a separate board, and a record made of the proportions of white used in each case. We can take, for example, a pure burnt sienna and paint out a strip. Then we take a second example : add ten parts of white, paint a strip, and make a note. Then, twenty parts, and so on. This experiment gives valuable information, not only as to the strength of the ‘ stainers,’ but also as to the appearance of a tint thus produced.

Subduing the Brightness

It may be imagined that it would be well to continue the experiments to the extent of adding a proportion of black to the different examples so as to produce shades. This, however, is not desirable, because such addition can only result in a very muddy appearance, which is far from pleasing. When a colour is too bright it is often subdued by the addition of a little umber, but this is a very primitive method and not one which is recommended. The proper colour to add to any given colour in order to sadden or render less bright is its complementary. Thus, a little orange may be added to a blue which is too bright, or, alternatively, a very little blue to an orange which is too bright. A little red should be added to a green to subdue it, or a little green to a red for the same purpose. The following colours may be added each to the other for the same object: yellow and purple, blue and maize yellow, blue and stone colour, blue and brown, scarlet and blue, orange and chestnut, lilac and primrose, and violet and orange yellow.

It may be added here that the above couplets of colours form more or less perfect harmonies, which can be safely used in decoration.

As already intimated, the art of colour mixing cannot be quickly acquired, and the process is rendered even slower than it otherwise would be, from the fact that the eye retains a colour for an appreciable length of time, and this interferes to some extent with distinguishing accurately the difference between various colours. Some readers will remember the very effective advertisement of a well-known soap-maker, in the shape of a star printed in bright red. The reader was requested to place the red star under a bright light and to gaze at it steadily for several minutes, and then to look at a white surface, such as the ceiling, when a star green in colour would be apparent and last some time. If, therefore, one experiments for any length with reds, the retina becomes excited and things look green.

One colour also materially alters the appearance of the colours adjacent. It is important to remember this fact in carrying out decorative work in general. The student is advised to draw a number of squares on a piece of compoboard, and to paint around some of them white, around others black, and others grey, and then to fill in the squares with a series of different bright colours, such as red, blue, green, yellow, etc. It will be found that the same red or blue or yellow presents a considerable difference in appearance when surrounded by the different ground.

Paint Mixing: General

We come now to a consideration of the subject of mixing paint in general. This is often done in a can into which is introduced the white lead or paste paint, which is first broken up by means of a paddle or stick. If a little linseed oil is put in the can and this is turned so that the oil reaches both the bottom and sides, it will prevent the paint sticking. Linseed oil is added gradually, and the paint is mixed until it is of the consistency of a very thick cream; then turpentine can be added. Two words of warning must be given here. First, on no account must dry colour be added, as it would be very difficult to get a uniform tint. The colours supplied ground in oil are alone to be used, and they can be thinned out on a slab or a piece of glass, being added in small quantities. One should remember that it is quite easy to put in any additional colour, but impossible to take any out. The second warning is not to add turpentine before the oil, as is sometimes done; this has a bad effect for some reason which is not quite apparent. Probably it arises from the fact that the turpentine dissolves the oil in which the lead is ground, and renders the admixture more difficult. Before the paint is applied, it will be necessary to strain it. For this purpose, painters’ strainers can be obtained for a shilling or so. The best strainers are those which have a wire netting which may be removed and another put in its place as may be required. A mesh of 50 will do for rough work, but for fine work 100 mesh is required. If the paint is at all rough, it will be necessary to pass it through strainers of varying degrees of fineness – first 40 mesh, then 80, then 100, then 120.

Colour Recipes

The following list of colour recipes requires a certain amount of explanation. There is, unfortunately, no system of colour standardisation in the decorating trade – a fact which leads to an enormous amount of confusion. The result is that if half a dozen decorators, thoroughly experienced in colour mixing, are asked separately to mix a given colour – let us say salmon pink, for example – it is more than probable that when the six colours are compared, no two will be exactly alike. Or again, a client, let us say, specifies a ‘ bottle-green ‘ finish, and a com-parison of a dozen colour cards, each issued by a different manufacturer, discloses the fact that there are apparently twelve definite and distinct opinions as to what a ‘ bottle green ‘ should look Hke. So it is with every other colour, and even black and white are not exempt. No one can be held to be right and no one wrong.

It is worth while adding that attempts have been made from time to time to remedy this state of affairs. In 1930, for instance, the British Standards Association issued a ‘ Schedule for Ready-mixed Paints ‘ (No. 381 of 1930). This contained fifty-seven colour patterns which, it was proposed, should be regarded as standard. Unfortunately, the trade as a whole did not adopt them. In 1934, the British Colour Council, a body primarily associated with the textile and fashion trades, published its Dictionary of Colour Standards, and there is some reason to hope that ultimately the colours laid down in this invaluable work will be accepted as standard by all trades in which colour plays an essential part.

Under existing circumstances, the value of the list of recipes which follows might at first sight seem to be doubtful. The entries, however, have been selected only after a careful comparison of the tint cards issued by the leading paint manufacturers, and the names employed may be taken as those most general in the trade.

It must be emphasised, also, that any proportions given must be regarded as very approximate, since the strength of the various stainers differs widely according to their quality, and according, also, to the source whence they are obtained.

The expression ‘ white base ‘ or ‘ white ‘ used in these recipes implies white lead, zinc oxide, titanium white, etc.

Alabaster

A yellowish white in colour; mix four parts of white with one of middle chrome yellow.

Amber

An imitation of amber can be produced by mixing equal portions of burnt sienna, burnt umber, blue-black, and orange chrome yellow, and adding a quantity of white lead until the desired tint is obtained.

American Red

Mix one part of yellow ochre with two parts of Venetian red.

Anemone

A reddish purple which may be made by mixing two parts of black, one of white, six of a bright red, and six of Prussian blue.

Apple Green

The simplest way to obtain this is to mix medium chrome green with about thirty times the quantity of white base, but other greens may be employed, with the addition of a little Prussian blue when necessary. Or a little orange chrome yellow may be added to the medium chrome green and white base. A good shade can be produced by mixing one part of white with four of yellow and nine of green.

Apricot

Mix middle chrome yellow with a little vermilion and add a very little lake.

Ash Grey

Lampblack and a little French ochre, added to white base, give this colour. Another mixture is as follows: two parts of burnt sienna, three parts of light ultramarine blue, sixty parts of white.

Begonia

A dark red-purple, which may be obtained by mixing four parts of lampblack, five of bright red, and four of Prussian blue.

Biscuit Colour

The purest tints may be obtained by tinting zinc oxide with Naples yellow. Ochre added to white, with a touch of umber, may be used.

Bismarck Brown

Six parts of black, one part of orange, and one of yellow.

Bottle Green

Mix together five parts of medium chrome green and one part of blue-black. A similar colour may be obtained by adding Prussian blue to blue-black and lemon chrome. Another shade is made by using four parts of black and one of green.

Brick

Use two parts of French ochre to one part of Venetian red and one part of white, adding more ochre if it is required to lighten the colour. This gives a good tint, sometimes called ‘ brick red,’ and is suitable for outside work.

Bright Scarlet

Mix twenty parts of vermilion, seven parts of pale chrome, and one part of golden ochre. A good vermilionette slightly toned down with yellow answers the same purpose.

Bronze Green

The usual method is to mix black with deep chrome yellow, but indigo may be used if desired. A much brighter colour is obtained by a mixture of medium chrome yellow, Prussian blue, and burnt sienna. Or the following recipe may be used: middle chrome green, five parts; blue-black, one part; burnt umber, one part. A light bronze colour may be obtained by adding more green or by using light instead of medium green. Other shades of bronze green may be got by adding a little lampblack to dark chrome green or by taking medium chrome green and adding lampblack and a little raw umber.

Buff

A useful series of colours may be obtained by mixing white lead or zinc oxide with ochre or a little black, Venetian or Indian red, and chrome yellow. If ochre is used, it should be of a good, bright quality, in which case one part of ochre to two of white will answer. A proportion of sienna may also be added. Creams, stone colour, and biscuit colour are produced in much the same way and in considerable variety by varying the constituents above given.

Buttercup Yellow

White base tinted with lemon chrome.

Cambridge Red

Vermilion, to which is added about one-twentieth part of Prussian blue, gives a colour sometimes known by this name.

Canary

Three parts of lemon chrome yellow to one part of white. Another shade is obtained by mixing two parts of white, six of yellow, and two of green. Some manufacturers make an extra light chrome yellow which they call by this name.

Carnation Red

Three parts of carmine lake and one part of white lead give a carnation colour, but a better result is obtained by taking pure vermilion as a base and adding carmine and zinc white until the desired rich colour is obtained.

Cherry Red

Mix together crimson lake, burnt sienna, and azure blue, or two parts of vermilion and one part of carmine.

Chestnut

Four parts of medium chrome yellow and two parts of Venetian red. One part of yellow ochre may be added if desired.

Chocolate

Five parts of burnt sienna and one part of carmine or lake. A less expensive colour is obtained by mixing Indian red and lampblack with a little yellow ochre. A touch of vermilion will clear and brighten this mixture. Black mixed with red will produce chocolate, but this gives a more or less muddy shade.

Cinnamon

Six parts of white base, two parts burnt sienna, and one part golden ochre make a good cinnamon, or French ochre, Indian red, and a little lampblack will produce the same colour.

Citron

To produce this colour, use Venetian red as a base and add one part of Prussian blue, two of chrome yellow, and two of white.

Claret

Mix two parts of carmine with one of ultramarine blue. A little vermilion may be added if desired, and this may render a little yellow necessary to tone down the colour. A less rich colour may be made by mixing Venetian red and yellow ochre, and glazing with crimson or madder.

Coffee

Five parts of burnt umber, two parts yellow ochre, and one part of burnt sienna.

Coral: This colour is made by mixing five parts of vermilion, two parts of white, and one part of chrome yellow. Another recipe for producing shades of coral pink is one part of white, three of red, five of orange, and three of blue.

Cream

The best and purest tints of cream are obtained by tinting zinc oxide with a little Naples yellow or by mixing eight parts of white lead, two parts of French yellow ochre, and a touch of Venetian red. French ochre and white alone are often employed. Equal parts of raw sienna and orange chrome used to tint white give a nice cream, but there are many other methods of obtaining this tint.

Drab

This can be made by using burnt umber and white base in the proportion of one of the former to ten of the latter.

Eau de Nil

Tint white base with medium chrome yellow, emerald green, and a touch of Prussian blue.

Egyptian Red

A dull yellowish crimson made by using five parts of black, one and a half of white, two of orange, and one of blue, and a very little red.

Fawn

Tint white base with a mixture of French ochre, Indian red, and lampblack. Alternatively, use eight parts white base, one part of chrome yellow, one part of Indian red, and one of burnt umber.

Flesh Colour

One hundred and twenty parts white base, two parts yellow ochre, and one part Venetian red will produce an excellent flesh colour, or mix eight parts of white base, two parts of orange chrome yellow, and one part of light Venetian red.

French Red .-Use equal parts of Indian red and vermilion, and glaze with carmine or permanent crimson madder.

Geranium

Nine parts of bright red and one of blue. Alternatively, Indian red, glazed with madder lake, may be used.

Gold

To obtain the colour known as ‘ gold,’ white base may be tinted with five parts of yellow ochre and one part of vermilion, or a mixture of light chrome yellow, French ochre, and vermilion may be used instead to tint the white lead.

Golden Brown

Sixteen parts of white base are mixed with one of burnt sienna and three parts of yellow ochre.

Grass Green

The colour sold as ‘ extra light chrome green ‘ makes a splendid grass green without any addition. If it is not available, lighten up medium or dark chrome green with chrome yellow.

Heliotrope

Two parts of white, three of bright red, and four of ultramarine blue.

Indian Pink

Tint white with a little Indian red.

Iron Grey

Eight parts of black with two of white and a little orange.

Ivory

Varying tints of ivory are obtainable by tinting zinc oxide with Naples yellow. The addition of a very little medium chrome yellow to white lead also produces an ivory, or a very little golden ochre may be used. Another way is to tint white very slightly with middle chrome and a touch of black.

Ivy Green

A mixture of French ochre, lampblack, and Prussian blue will produce this.

Lavender

Three parts of ultramarine blue and one part of carmine, added to white as a base, give a very good lavender tint for inside work. It should be added, however, that carmine, besides being expensive, is not permanent.

Leather Brown

Four parts of yellow ochre, three parts of Venetian red, two parts of white, and one part of blue-black give a rich leather brown. If a lighter tint is required less black should be used.

Light Oak

Add French ochre and Venetian red to white as a base.

Light Pink

Tint white base with a little pure vermilion. The word ‘ pink ‘ does not bear any very definite meaning, as almost any bright red, such as carmine or crimson, added to plenty of white gives a good pink, just as vermilion does, but of another hue. A very pretty and useful pink is made by adding white to permanent crimson madder.

Light Red

This term might be applied to any tint of red lightened up with white. It is, however, a definite name of a water colour, which is also called ‘ burnt ochre,’ ‘ burnt Roman ochre,’ and ‘ terra rosa.’ It is obtained by burning yellow ochre, and it is quite permanent.

Light Salmon

Tint white base with raw Italian sienna, burnt Italian sienna, and burnt Turkey umber. Or tint white with any bright red, toning down with sienna.

Light Stone

Tint white with French ochre and lampblack.

Lilac

A great deal of difference of opinion exists as to this tint. One part of ultramarine to one part of bright carmine, added to eighty parts white base, gives a very good lilac. A cheaper way is to use Indian red and lampblack as a tinting colour, or rose pink may be added to the base only. Yet another method for producing a lilac is to mix three parts of bright Indian red, three parts of white, and one part of ultramarine blue, but less white is preferred by some painters. A touch of yellow will help this colour if too raw for the purpose.

Magenta

Carmine and vermilion, with a little ultramarine blue, produce this colour.

Mahogany

Mix orange and yellow in equal proportions with three times the quantity of black.

Marigold

This is obtained by mixing a very little bright yellow with orange chrome.

Maroon

This colour is obtained by mixing carmine and blue-black, and adding a small quantity of medium chrome yellow. It may also be made by mixing one part of ultramarine blue with three parts of Tuscan red. This gives a tint that is often considered a little too red, but this defect may easily be remedied by adding more blue. Some painters add ivory black and a little chrome yellow to carmine.

Mauve

Four parts of cobalt, twelve parts of oxide of zinc, and one part of carmine lake give an excellent mauve. Alternatively, white may be tinted with ivory black, carmine, and ultramarine.

Moss Green

Tint white base with French ochre, a bright green, and a little lampblack.

Mulberry

A very dark purple, obtained by adding a little blue and just a tinge of red to black.

Old Gold

Use middle chrome with a little vermilion and burnt sienna and a very little cobalt. A cheaper colour may be made by mixing ochre and burnt sienna.

Old Rose

Tint white base with French ochre, Indian red, and lampblack; Venetian red and a very little lampblack may be used if desired.

Olive

Mix together ten parts of lemon chrome yellow, one part of ultramarine blue, and one part of light Indian red. Another method is to use eight parts of lemon chrome yellow, one part of blue-black, and one part of Prussian blue. A third method is to add equal portions of Prussian blue and lampblack to lemon chrome yellow for a base, or the base may be ochre instead of chrome, and a little of the yellow be added.

Orange Vermilion

The pale shade of vermilion orange lead comes nearest to this colour. The tone may be made by adding chrome to vermilion.

Pea Green

Forty-eight parts of white base and one part of chrome green will give this colour.

Peacock Green

Seven parts of white, fifty parts of emerald green, and forty-three of Prussian blue will give this shade. A little yellow is sometimes added. The colour is best produced by giving a final transparent coat over a ground colour. For the ground, mix a rich green, a very deep Brunswick green, and middle chrome. Over this apply a very thin coat of a deep bluish-green made from Prussian blue and lemon chrome.

Pompeian Red

Small quantities of bright red and orange are mixed with black to produce this shade.

Porcelain Blue

Mix one part of white and chrome green with four parts of ultramarine blue and a touch of black.

Portland Stone

Mix equal parts of yellow ochre and raw umber and lighten up with white until the desired tint is obtained.

Primrose

Ten parts of white, three parts of green, and four of yellow will give this light greenish yellow. Another shade is got by mixing one part of orange, two parts of green, and five of yellow.

Purple

Light Indian red, four parts; white, three parts; ultramarine blue, two parts. A mixture preferred by some painters is made by mixing ultramarine and vermilion with a little white.

Quaker Green

Mix equal proportions of Venetian red and medium chrome yellow and add blue-black. Add to this mixture a quantity of chrome green equal in bulk to the three.

Red Terra-cotta

Use equal proportions of burnt sienna and white. The tone may be varied by the addition of either of the umbers and the chromes. A good bright terra-cotta is also made by using Venetian red as a base and colouring up with ochre and a touch of lake.

Robin’s-egg Blue

Use white for base, tint with ultramarine until a fairly strong blue is obtained, and then tinge with a little lemon chrome green.

Rose

Five parts of white base mixed with two parts of carmine give a rose suitable for inside work only.

Rose Carnation

Mix together one part of rose madder and eight parts of oxide of zinc. This is a beautiful colour, but the madder is too expensive for use except by artists.

Royal Purple

Mix one part of vegetable black, one and a half of rich red, and seven of Prussian blue. Some manufacturers make this colour ready for use.

Russet

A good russet shade is got by mixing twenty parts of black, twelve parts of red, ten of orange, three of yellow, and five of green.

Sage Green

Tint white base with four parts of light chrome green and one part of ivory black, or the white may be tinted with a mixture of French ochre, lampblack, and Prussian blue. Or add raw umber and chrome green in the proportion of about one part of the former to two parts of the latter to white until the desired shade is obtained.

Salmon

Six parts of white base, one part of vermilion, and a little lemon chrome yellow. This mixture produces a colour somewhat bright. Another salmon colour is made by a mixture of raw sienna, burnt sienna, and burnt umber. A tint preferred by some is produced by adding to the white, Venetian red, burnt umber, and French ochre. Another method is to add vermilion and golden ochre to white, which gives a nice bright colour. Venetian red and chrome, added to white, give a duller colour. Still another mixture is Venetian red, vermilion, yellow ochre, and white.

Scarlet Lake

This colour is manufactured from a mixture of vermilion and alizarin crimson. It is suitable both for oil and water, and is permanent. A colour very similar may be obtained in one of the many vermilionettes on the market. It will be convenient to remember that all vermilions should be lightened by the use of pale chrome instead of white lead. Lead takes down the brilliancy of the colour, producing a pink.

Sea Blue

Two parts of Prussian blue, three parts of raw sienna, thirty parts of white.

Shell Pink

This colour is sometimes made by adding a little good Indian red to white, but some decorators prefer to use vermilion with a little chrome yellow and burnt sienna.

Shrimp Pink

Mix Venetian red, burnt sienna, and white, and add a little vermilion.

Silver Grey

Tint white base with French ochre and lampblack, or yellow may be employed instead of the ochre if preferred. White lead tinted with a little lampblack and indigo gives an excellent silver grey.

Stone

Mix together five parts of white base, two parts of French yellow ochre, and one part of burnt umber. By adding a little raw umber, the tint may be varied as desired. Alternatively, tint white with medium chrome yellow and burnt umber.

Tan

Ten parts of burnt sienna and four parts of medium chrome yellow with three parts of raw umber. White lead and burnt sienna, to which has been added a very little lampblack, will also produce a tan.

Terra-cotta

Mix together two parts of white base to one part of burnt sienna. One of the best ways to produce a good terra-cotta wall is to give a good undercoat of white lead, orange chrome, and a little Venetian red, and when dry to apply a finishing coat made from Venetian red and a little orange chrome to which had been added a little white. See also under ‘ Red Terra-cotta.’

Turquoise Blue

Two parts of cobalt blue, one part of emerald green, twelve parts of white.

Venetian Red

This colour is an oxide and is sometimes called ‘ Mars’ orange.’ It is one of the most useful that the house painter has, being cheap and having good covering power and body. It may be used both in oil and water, and is quite permanent. It is not very good for tinting purposes. It would not, of course, be often imitated, but Indian red – a very similar pigment – could be tinted with Venetian red. Or it may be imitated by mixing vermilion, yellow ochre, madder carmine, and a little Cappagh brown, which is an artists’ colour and is rarely used by house painters.

Wine Colour

Add a little ivory black to a mixture of carmine and vermilion. Or use Indian red mixed with a little black or umber, and glaze with madder.

Mixing Paste White Lead

White lead is ground in oil and comes to the painter in paste form. It is marketed in three different consistencies – stiff, medium, and soft – to meet varying requirements, and is knocked up by the painter. The best way of doing this is as follows:

The vessel into which the paint is to be mixed should be of such size that when the requisite amount of paste is placed in it, it is not more than about one-third full. It is a good plan first to place a little oil in the vessel – -just about enough to ensure that, by tilting and rotating the latter, a thin film of the oil is deposited on the surface of most of the interior. This helps to prevent the paste from sticking to the sides.

The paste is then put in and a little oil added to it; by means of a wooden paddle, the lead and oil are worked together, so as to make the mixture softer and more uniform. More oil is added, a little at a time, until some degree of fluidity is obtained, though the mass should still be rather too thick to apply by brush. At this stage the driers should be introduced and well stirred in, followed by more oil until the necessary amount of the latter has been used. Finally the turpentine or white spirit should be put in, again with thorough stirring. After straining, the paint is ready for use.

If a coloured paint is wanted, pigments ground in oil should be used; they should be reduced to a fairly thin paste with linseed oil and turpentine or white spirit and added, a little at a time, to the mixture, care being taken that they are evenly distributed throughout it, by stirring. By incorporating them gradually in this way, instead of putting them all in at once, more complete and even dispersion is obtained, and there is far less risk of making the colour too strong. Straining before use is even more important with tinted paint than with white, because the stainers themselves may contain lumps or fragments of skin.

After paste white lead has been removed from the keg, the sides of the latter should always be scraped down and the remainder of the contents levelled off. A good deal of material is wasted by failure to do this.

Paint is better if allowed to stand a clay before using and it should be strained through a fine sieve, or better through cheesecloth, shortly before it is wanted on the job; this takes out paint skins as well as dirt and lumps, and ensures good mixing.

These directions should be followed strictly, for if the paint is not well mixed it will be impossible to do a good job with it. Always let it be remembered that turpentine is a thinner or more mobile liquid than oil, and that a quart of it will thin a batch of paint as much as two quarts of oil.

Matching Colours

The accurate matching of shades in paint depends largely upon individual aptitude. Proficiency in the art can be acquired only by intelligent study of the strength of pigments, the effects which are produced when they are diluted with white, and the exact changes which result from adding any one pigment to another.

The process will vary, to a certain extent, according to the nature of the sample which is to be matched. This may take one of many forms: it may be a liquid, such as a paint, stain, or dye; alternatively, it may be a dry sample, such as a small panel from a tint-card, a piece of wallpaper, a portion of paint film, or of an old painted surface, fragment of silk or other fabric. Each of these requires special consideration.

It frequently happens that the client selects a pattern finished with a gloss and demands an exact match in a flat paint. Actually, the two can only match from one viewpoint: they can be made to match when viewed at right angles, at a sharp angle, or at a wide angle, but only in one of these angles; and immediately the viewpoint is changed – as, for instance, when a person walks through the room – differences in shade and appearance are unavoidable.

Similarly, it is impossible to match paint exactly with a piece of fabric. The latter is made of semi-transparent fibres with an indented or broken surface, giving many different shades and reflections, whereas the paint is relatively opaque and possesses a flat, uniform surface.

Difficulty occasionally arises when a particular blotch of colour in the pattern of a wallpaper is chosen as a sample. Most wallpaper patterns are printed with semi-transparent colours, and a special effect is obtained through the striking-back of light from the white-paper surface through the tinted colour. Again, patches of colour on wallpaper seldom present that uniformity of shade obtainable on an ordinary painted surface.

Providing that these limitations are realised, however, reasonably accurate matching to almost any kind of sample can be carried out by a skilled man. Those whose experience is limited should never attempt to make up a colour with the full amount of materials which, according to calculations, the job will require; it is far better to take half the estimated amount and then add stainers as directed, keeping in mind the quantities used of each, until the correct colour is obtained. It sometimes happens that a great deal more stainers have to be added than was first thought necessary, either from bad judgment or because the stainers are lacking in strength. Alternatively, if too much is added, it can be Hghtened up with a portion of the pigments held in reserve. This method will involve a little extra labour, but it will probably prevent a good deal of wasted material.

Matching Liquid and Dry Patterns

The actual matching should be carried out in a strong light, northern preferred. The sample should first be thoroughly stirred, in order to ensure freedom from sediment, and a small quantity applied to the centre of the pattern board, which should be painted white. The sample should be rubbed out in a circle, when some idea of its composition may be obtained, and whether it has been made up in turpentine, oil, or varnish, according to the gloss it retains upon drying. The principal colour in the sample should be produced in the match, with a smaller proportion of any other colour needed, until approximately the same shade is obtained. A comparative test can then be carried out by taking a clean palette knife and dipping it first right into the sample and then part way into the mixing. If no difference between them is discernible on the knife, the match may be regarded as sufficiently close for most ordinary purposes.

It must be emphasised, however, that this test can only be considered of value when a gloss paint is being matched to a gloss sample or a flat to a flat. When a flat paint is being matched to a gloss sample, it will give no indication of the ultimate effect, and it will be necessary to paint both sample and mixture on to the same board and allow them to dry before any serviceable comparison can be made. Many experienced decorators are in the habit of adding a small quantity of a brighter or richer colour to the flat paint in order to obtain an illusion of gloss, but this requires a great deal of skill and knowledge of colour. Similarly, when a gloss paint is being matched to a flat sample, the gloss of the mixture can be toned down with white or grey to obtain a fairer basis of comparison.

To match up to a dry pattern is rather more difficult than when a liquid sample is provided, owing to the deepening of colour which takes place during the process of drying. This deepening is more pronounced with some pigments than with others, and is particularly noticeable with certain blues and with greens derived from a mixture of blue and yellow. ^ If the paint to be matched is dry, say on woodwork, a little of the new paint should be painted out on a board and placed side by side. If, as often happens, the paintwork is to be finished to match one colour in a wallpaper, it will be in most cases necessary to modify the match somewhat in order to allow for the effect of other adjacent colours in the pattern.

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