Renewal for previously painted surfaces

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Signwriting in days gone by.

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Glazing in days gone by.

Renewal work in days gone by

Successful painting means more than simply spreading paint. The builder must be able to see the end of a job from the beginning, and in severe competition, price it accordingly. It is not usual to specify just how many coats of paint shall be given for renewal work; the great point is that the job on completion shall be satisfactory and give satisfaction over a period of years. Only so can a successful jobbing business be built up. Many decorators enter houses, not as tradesmen but as friends. The success that matters depends on many things: judgment of surface condition, right selection of materials, and appreciation of colour.
Where a complete colour change is desired, especially from dark to light, the builder may be tempted to make experiment with water paints in order to save a coat of oil paint.
This often proves false economy, for if a water paint is used over an oil-painted surface, it will generally be found that the following coat of paint will sink into the water paint, whereas if oil paint were used throughout, there would be an equal gloss or half-gloss, as the case might be.
Misuse of White Paint.
Green-eau-de-nil, sage, leaf-green-wall surfaces are difficult to cover if the finish is to be white or a deep cream. It is impossible to overcome the green in less than three coats even if a dense white is used, that is, if fine brushwork is desired. The green may be covered more easily if the first coat is a decided pink tint, and if the wall were a shrimp pink or bright terracotta, the first coat could with advantage be tinted green. Painters often stand by white whatever the ground, whereas if the correct tint were used-a tone complementary to the existing ground colour-the wall would be covered more easily. It is not an uncommon thing to hear a foreman painter declare, and thus advertise his incompetency, that some surfaces have not been properly covered in four coats.
White, again, is not the correct thing for a ground to be finished a middle green. Whatever the finish, and whether it be flat or gloss, a better result will accrue if the ground is made to approximate the final colour.
Paint to-day is far from being low in price, but the deciding factor on most jobs is not material but time.
What shall be done with old painted work 'I It will be found that no two jobs are alike. A foreman may make a reputation on one job and lose it on the next, all because he worked not on surface judgment but by rule of thumb.
Preparing Old Work.
Old work in good condition should be washed down with weak soda water or one of the trade sugar soaps, be well rinsed with cold water, and leathered. It may be rubbed down during washing with pumice stone or waterproof glass-paper, or afterwards with ordinary glass-paper, when it is dry. The chief thing is to see that every trace of soda is removed; subsequent painting will prove whether this has been done.
Omitting the washing is a penny-wise-pound-foolish policy, since there is always a greasy film on old paint and enamel which militates against proper hardening of subsequent painting. Besides, an unwashed surface is always more difficult to paint.
If this surface is to be repainted the same tone of colour, touch up any bare or bad places in a colour to match. Repeat the process, if necessary, and stop up all cracks and bad places with hard stopping. By this time the surface should look uniform. Two coats well brushed out should make a good job; if the final one is gloss or enamel, keep the first coat flat or matt.
"Crazed" and Blistered Surfaces.
Old work, badly crazed, presenting what is sometimes called a " crocodile" surface, where price allows, should be burnt off or stripped with one of the spirit paint removers. For a cheaper job, after washing down, fill up with paste fillets, one of the many on the market, using a broad knife for the purpose, and rub down smooth. Repeat the process, for it will be impossible to do justice to the surface in one operation. In this instance ~ water-paint filler will be an advantage, as it will have the effect of preventing further blistering. Indeed, the first coat here might be one of water paint, used round, and well brushed out.
A blistered surface generally suggests the need of paint removal to the ground, yet for some unknown reason blisters often appear only in places.
The builder should remember that a surface already blistered is liable to blister worse once it is repainted, the liquid in the new paint allying itself with the sun, to the confusion of the painter. It is a serious business to have to burn off after a job is practically finished.
If blisters show on a front door or other conspicuous part, do not hesitate, but remove the paint to the ground.
Where the blisters are what may be called isolated or local, cut them out and fill up with a suitable filler coloured to approach the prevailing ground colour; touch up, and bring level with the old work. On a ground of this sort the less paint applied the better. H the work has been varnished, it may be advisable to give a thin coat of paint mixed in varnish and turpentine, and finish with a clear varnish.
Removing Paint.
A surface crazed or blistered beyond repair should be burnt off or stripped with one of the paint removers. It is well to avoid caustic mixtures, as, however carefully they may be washed off, and ihough the surface may be neutralized with vinegar or weak acetic acid, there is always a doubt about them. The blow-lamp is generally acclaimed the safest. See that the men use the lamp from the bottom of a door upwards, otherwise heat and time are lost, and scorched wood results. During burning-off, mouldings can be cleaned with wire brushes or wire wool, but this should be done at the time and not -.Iter the paint has become cold, hard, and stubborn. Whether the surface is finally rubbed down dry with glass-paper, or with pumice stone and water, or pumice. stone and turpentine, is a matter of opinion; but it should be thoroughly, even ruthlessly, rubbed down at this stage.
The burning-off process tends to make knots prominent. Any that offend should be undercut with a gauge, knotted, and filled up. Since the wood is seasoned, red lead need not be put in the priming coat. In fact, if one of the paste fillers is used, it is advisable to fill up direct with the broad knife and follow with a coat of the filler thinned down like paint. This may be rubbed down to a smooth, level surface.
A Model Specification.
A specification for work to be burnt-off and finished with gloss enamel could well be as follows :
Burn off, undercut bad knots, knot and fill with enamel filler. Give a coat of thin enamel filler. Follow with a coat of white lead paint made with linseed oil and turpentine in equal parts; second coat, oil 1 part, turpentine 3 parts; third coat, oill part, turpentine 4 parts. Finish with enamel. For cheaper work, one coat could be cut out. Woodwork and walls previously painted to be finished in old-time flatting.
Rub down with pumice stone and water, using a little soda or other alkali inthe water. Wash clean. First coat should be white lead in linseed oil and turpentine equal parts, second coat, 3 parts oil and 1 part turpentine. Flatting should be turpentine alone, using the ordinary quantity of drier and adding a little linseed oil or, better, glossy varnish for a binder.
Using Flatting Paint.
To make up a flatting paint and use it right away on large surfaces is courting trouble.
Make it up a day previous to use. If made rather thick, pour turpentine into a tray to let the air get at it, and use this for thinning. To a gallon of flatting add half a cupful of cold water and stir in. A flatting made on these lines will work cool and dry out evenly. For wall surfaces it is best stippled.
Flat and Gloss Enamel.
It is well to use one particular firm's brand unless any other is specified. By this method painters get used to the enamel and know ita vagaries. It seems a pity there is not a recognized standard. for enamel work. Some shows the groundwork because the enamel is brushed out after the manner of a boot polish. Another job has the real enamel or china-like surface. There is no comparison in the value of these two surfaces. One is not the equal of an oil paint, either in appearance or wearing qualities, whereas the other is satisfying to the eye and will wash repeatedly.
Old enamelled work in good condition should be washed down and well pumice-stoned during washing, all bad places stopped and touched up. If properly washed and rubbed down -that means that the surface should be slightly abradedone good full coat of enamel will make a lasting job. It will take slightly longer to dry, and, consequently, dust must be kept down. If a coat of ground colour is applied, add a percentage of glossy enamel to it. To a gallon of paint add 1 quart of the finishing enamel. Flat enamels should be applied over a dead flat paint, either white lead or zinc. It is sometimes stippled, though if properly laid on, the stippler is not advised. Enamel a door in sections, whether flat or gloss. Begin with the panels, and sometimes do the moulding with them, muntins and rails first, finishing with the stiles. In some instances it is well to leave the mouldings until last.
Varnish paints require a flat or matt ground similar to that for enamel. Often the addition of a modicum of colour to the varnish is an advantage.
Quick Enamelling.
There are quicker methods of enamelling which may be followed as occasion demands; tor example, one coat of dense white followed with gloss varnish or enamel. By dense white the maker's undercoating is indicated.
Old work touched up, a coat of dense white undercoating, and one of enamel. These dense white undercoating paints seldom bear retouching, otherwise the parts show after the enamel is applied.
All preparation, even the extra coat, if that is sometimes necessary, should be of the builder's own mixing, preferably of white lead, and be applied under the dense white undercoating.
A second application may be given, however, by adding to the undercoat a little gloss enamel.
Plat Wall Pinishes.
Flat wall finishes are gradually ousting water paints for plastered surfaces. Exorbitant claims were made for water paints, especially under the head of washing. They soil quickly and may indeed be washed, but from the floor upwards. The old-time flatting which they were made to replace cannot only be washed, but scrubbed repeatedly.
Flat oil finishes should be applied strictly on the lines suggested by the makers. The chief point to remember is that the surface must not be porous. Suction must be stopped, and it is generally advisable to use the stopping-out liquid indicated. These paints are best applied with a wide, flat wall brush. They must be laid on freely, and may be brushed in all directions. Retouching must be avoided, however great the temptation.
Re-enamelling Baths.
Baths that are to be re-enamelled should be washed with weak alkali solution, rubbed smooth, and washed with plenty of cold water. Attend to taps, since a leaky tap will spoil the work.
Zinc paints are comparatively useless for bath painting.
A suitable ground may be made from white lead ground in turpentine and brought to a proper consistency with japanner's stoving varnish. Follow with a coat of bath enamel.
Another method is to use bath enamel throughout. Touch up bare places, and allow to dry. Give a coat of bath enamel thinned slightly with turpentine, brushing it out bare. Follow with a full coat of the enamel.