In general new paintwork on soft wood will last longer if a four-coat system of painting is used. This consists of one coat of primer, one or two coats of undercoat and one or two coats of top coat. A paint system that is used internally should not contain a lead primer or any other toxic material, particularly where children may be present, since lead is poisonous. Avoid using lead-based paints on such surfaces as sills, stairways, nursery woodwork or furniture. Undercoat should be applied after the primer coat has been allowed to dry for at least 48 hours. Before applying the undercoat, check that the primer is dry, but not too hard, and that any filling or stopping necessary is done. Lightly rub down the surface with a wet-abrasive paper, and then wipe off with a leather.
Once the surface is completely dry, apply the undercoat. Undercoat has more colour pigment than the top coat and should be similar to, but not match, the top coat.
The quality of the top coat is dependent on a sound undercoat. To achieve a dense base for the top coat, it is preferable to apply two undercoats. If there are uneven patches in the undercoat they will show through the top coat. This should be an opaque covercoat, free as far as possible, from brush marks.
Avoid putting on too much paint too lightly which could cause sagging or ‘curtaining’. The skill comes in spreading the paint as far as possible, while keeping the density of colour. When the undercoat is completely dry, after about 16-20 hours, rub down lightly, clean with a tack cloth, and apply the top coat.
Use a brush slightly narrower than the area to be painted. Hold the brush in a flexible position. The movement of the brush is controlled by the wrist and hand and should be relaxed. Painting of detailed features such as beading requires the firm control of the forefinger, second finger and thumb. Any grip in painting should be relaxed, or the movement will be tiring and lead to fatigue.