Better to paint plaster and how to choose the right composition and color

Gypsum is one of the most demanded materials for interior and exterior decoration. It is harmless to humans, inexpensive, suitable for creating complex shapes, does not frost crack. But when creating a design, you often want to change the dull white color of the material. It is not difficult to choose what to paint gypsum with, its porous surface absorbs pigments well, and the paint performs not only a decorative, but also a protective function.

Hardware Features

Plaster is a building material of natural origin. The mineral is extracted from the bowels of the earth, burned, crushed to a powder state, mixed with water until homogeneous. The use of gypsum mortar in construction is varied:

• Wall cover;
• creation of stucco moldings, statues and other small artistic and architectural elements;
• output of bricks, decorative slabs;
• fasteners at an intermediate stage of construction.

The standard color of the material is white or grayish white. Plaster elements are used to decorate interiors, facades and personal plots.With the help of plaster you can create a figure of any complexity and pretentiousness, in any style.

The material is popular because it has many advantages:

• hardens quickly (therefore it is impossible to hesitate to complete the work);
• has a "breathing" porous structure;
• not suitable for direct flame;
• weighs a little;
• easy to process, does not require complex installation activities;
• absorbs paint well, does not require a complex staining procedure;
• ecological;
• is relatively cheap.

Appropriate dyes

Gypsum has excellent adhesive properties, that is, products actively absorb moisture and liquid substances, including paints and varnishes.

What dyes, impregnating and protective compounds can be applied to gypsum:

1. Acrylic, water-based, water-dispersion paints. Acrylic is most in demand for processing. It gives the surface a decorative look, protects it from negative external factors, is resistant to ultraviolet light, vapor permeable (due to which it creates optimal microclimatic conditions in the room), elastic (the probability of cracking is low ).
2. Iron and copper sulphate are impregnating compounds that increase the strength of gypsum. The second goal is to give the surface a pleasant shade: light blue with the addition of a substance containing copper, light yellow - a substance containing iron. For staining, vitriol powder is dissolved in water. Plaster products are placed in the solution so that they do not touch each other.
3. Wood stain creates a beautiful shade. But you need to work carefully, at first it is advisable to apply a little composition to a small part of the plaster product. Modern manufacturers often add substances to gypsum that react negatively to stains.
4. Clear varnish is a way to enhance the shine and vibrancy of a colored coating. Varnish protects the painted surface from negative external factors. It can also be used to treat unpainted gypsum to a glossy finish. Since the paint is quickly absorbed into the plaster surface, products can be varnished almost immediately after staining.
5. Gold and silver tints. Sold in art stores.
6. Dyes for coloring plaster mortar. They are usually added to the composition before pouring the finishing bricks.
7. Red lead is an orange-red or red-brown paint of natural origin, obtained by oxidation of lead or iron. Has high protective properties.
8. Potal is a thin sheet. Based on an alloy imitating gold leaf, silver or aged bronze.

Look at Also

What oil paints can and cannot be mixed, rules and color chart

How can the material be processed

Since gypsum tends to absorb moisture over time, it must be painted immediately after production, otherwise the paint will not adhere well to the product. The paint should be applied to a completely dry, even surface without chips, cracks and other defects.

If you have to work with an old plaster surface, you must treat it before painting it:

1. Remove dust and dirt spots. In this case, it is impossible to heavily wet the surface.
2. Remove the remaining paint from the previous coloring. Grinding plaster is not easy, the work takes time, especially when the molding is under the ceiling.
3. Treat the cleaned surface with a primer. You can buy a ready-made composition at a hardware store, or you can dilute polyvinyl acetate glue in water in a ratio of 1: 4.
4. If necessary, impregnate with a composition that makes the material less susceptible to moisture and other negative factors. Some impregnations may be incompatible with colorants, therefore the instructions should be read before using the formulations.
5. Let the plaster dry.

Rules for choosing the right paint

The choice of paint is determined by the purpose and object of application:

• stucco moldings, statues, bas-reliefs are painted with acrylic, water-based or water-dispersible composition;
• to reduce sensitivity to moisture, an acrylic composition with silicone is used;
• so that the gypsum product retains its color forever and white areas do not appear in places of cracks and chips, the color is applied at the stage of mixing the gypsum solution;
• to create the effect of antiquity, gypsum is treated with linseed oil (the effect will appear gradually);
• to imitate a terracotta coating, gypsum is treated with rosin and shellac varnish diluted with alcohol (the effect will also not appear immediately);
• to create the effect of a metal surface, a sheet is glued and varnished on top;
• To simulate a wax surface, gypsum is covered with wax diluted with acetone, with the addition of yellow oil paint, the dried surface is polished with a soft cloth.

Regardless of the type of paint, you need to make sure that it is suitable for plaster coating. The main thing to watch out for is consistency. The paint you choose should not be too thin. Otherwise, ugly spots will appear on the plaster product. Paint, in which clots are visible when shaking, should also not be used: either the expiration date has expired, or the products have been stored under inappropriate conditions.

Look at Also

What is better and cheaper for gluing wallpaper or painting the walls, the pros and cons

If the pigment is added to the gypsum solution, you will have to tinker with stirring. The solution is quite dense, it is problematic to achieve homogeneity. When adding paint, it should be borne in mind that the pigmented solution after drying becomes lighter than in a liquid state. Therefore, to achieve the desired shade, you need to pour a little more paint than it seems visually optimal.

How to paint correctly

For convenient coloring of gypsum, use:

• spray gun (if there is a lot of work);
• airbrush (for linear coloring);
• brushes of different sizes (for drawing details);
• sponges (for coloring the protruding elements and creating a "stone" effect);
• sandpaper (to create the effect of "old age").

Purchased gypsum stone should be left to dry for a few days in a shaded place. You should paint in a well-ventilated place, leave the painted plaster parts there until they are dry. For uniform coloring, each element must be treated individually.

Acrylic is supposed to be applied over gypsum in 3 layers. If you want to create an effect of color irregularity, first coat the surface with a dark paint, lightly sand the raised areas, then apply a light paint.

After drying, the painted gypsum surface fades, so it is varnished. If you don't want to give the product a glossy look, use a matte varnish. It will intensify color without shine. Any varnish is applied to the gypsum in 2 layers.

To imitate marble, a glaze is used - paint of different shades is applied in layers. To achieve the "old age" effect, heat the drying oil, apply it well and evenly with a flute brush, do 2 layers.After a short time, the coating will look like aged marble.

How can you paint plaster for bronze

Imitation of metal is a popular design option for plaster. To complete the work, you need oil paints of the desired color, acetone solvent, a brush, sandpaper. At the first stage, they paint with light paint in 3 layers, and they put it thinner on the convex areas of the relief, and thicker in the hollows. Dried paint is treated with sandpaper, wiped with a cloth soaked in solvent.

Look at Also

13 main paint defects, their causes and how to eliminate errors yourself

In the second stage, the bronze paint is well placed. When it dries, a third coat of bronze is applied, diluted with a solvent, containing wax for a matte effect. After drying, the painted surface is lightly treated with emery paper on the protruding areas, then a mixture of talc and chromium oxide is rubbed with a soft cloth.

What varnish to use

Varnish improves the appearance of the product, increases the service life. 3 types of varnish are suitable for processing plaster.

Shellachny

An alcoholic solution of shellac, a natural resin, is often used in finishing work. Creates a thin, clean protective film. To make the coating more decorative, a composition of shellac with the addition of dyes is used.

Acrylic

Ideal if you need to protect gypsum from moisture and other negative factors. The acrylic coating not only protects well, but also has a decorative appearance, it can be glossy and matte. The first option makes the surface glossy, the second is suitable for facing wall tiles and gypsum bricks, when it is impossible to spoil the imitation of masonry.

Oil

Such a varnish is based on natural and synthetic resins, which give a smooth appearance to the structure. A thin film forms on the surface of the gypsum, after drying it protects against negative factors and mechanical influences.

Rules for further care of plaster products

Plaster products last a long time with proper care. Tinted plaster is much easier to clean than uncoated plaster. It is enough to periodically clean the painted garden figurines from dust and dirt with a damp cloth. To remove dust from stucco elements, it is better to use a vacuum cleaner with attachments that allow you to clean hard-to-reach places of plaster reliefs. Do not use detergents and abrasives.

Antifungal agents should be used for preventive cleaning of garden decorations and wall bricks. For the winter, the outdoor decor is brought to the pantry so that the coating does not crack under the influence of extreme temperatures.