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Palette knife for painting
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Painting with oil paints
If to imagine the picture plane in cross section, we can see that it is composed of several different material layers, located in order of the process of creating the picture. This is painting framework, sticking, base soil, undercoat, the main art layer, cover layer.
Art framework
Unlike the art basis for water color, gouache, the surface of the basis for oil painting requires special training - sticking and priming.
Oil paints are done on hard surfaces (wooden planks, plywood).
Plywood and boards must be dry, without any signs of former branches, influx.
Boards are imbued with linseed oil, heated above 100 degrees.
Boards can also be processed through heated water. Then dried at temperatures no higher than 50 degrees. Then they are process with the solution of sublimate in ethanol.
Metal panels, glass are sometimes used as the basis.
Glass is drawn with a thin layer of paint, mixed with turpentine varnish. The surface is not primed but is simply cleared of dust.
Cardboard as a foundation, is very hygroscopical, and losses shape. If handled roughly, can be damaged.
Canvas, as a basis for painting, is most prevalent. It is durable, elastic, light, has a good texture, large size.
For painting canvas must have several qualities - be tough, tight, no knots, etc.
The paintings drawn on canvas, are less strong than those on boards, because the air and humidity have easy access to the base and color layer. In addition, the canvas is prone to mechanical damage - it can poked, ripped, cut, etc.
Canvas is put on a stretcher before the drawing starts. Stretcher has to be strong and light. It is made from dry wood without cracks, mold, without signs of former branches.
Stretchers that are larger than 110-130 cm. in most cases are produced with two crossbars, that protect the stretcher from bending.
The new canvas should be, preferably, washed first in hot water to remove finishing material from it.
It is better to stretch the canvas in slightly moist conditions.
Sticking and priming the foundation.
This is a difficult phase in the work. The quality of the soil affects the quality of painting, preservation of paintings.
Preparation of glue (joiner's, osseous).
Glue is grinned down, fill with boiled water and keep it for about a day until it swells.
Then the water is drained, glue is spilled and stirred. Then again it is filled with boiled water, mixed and boiled for 40 minutes in the glue pot, not bringing it to the boil.
The cooked glue is poured through a small hole fabric. Then glue is added with boiling water and plasticizing agent. The solution is mixed.
The glue solution must be strong. Sticking has to be applied quickly. Excess glue should be removed. Glue should soak well into the canvas. Gelatin is used for sticking, joiner's glue, caseic, starch.
Canvas that has undergone the procedure of sticking can be applied with soil of all kinds. Soil consists of a binder, glued fillers and various additives.
Animal and vegetable glue are used as the sticking agent (gelatin, etc., vegetable oils, egg yolks).
In order for the soil to be more elastic, glue solution is added with glycerin, honey, castor oil, etc.
To prevent soil from mold and rot its composition is added with preserving agents – formalin and other.
Pigments, fillers provide color, texture, structural mass and absorbent ability.
The classic filling is chalk. Chalk is sometimes used in a mixture of zinc whiteners.
Soil prepared with the use of chalk, strongly absorbs binders of paints, stains can appear.
In addition to chalk, fillers can be plaster, kaolin, flour, ash, sawdust.
Half-oil soil is soil with oil paint. More often whiting lead is used for this.
Oil soil is made of specially prepared paint. Sticked basis is applied with a layer of soil by a palette-knife (small layer), which is then rubbed into the canvas, and evened up. After drying second layer is applied, thinner layer of much more liquid paint.
Emulsion soils are used since the nineteenth century.
The combing agents in the soils are emulsions. When dried, they produce a transparent film with matte surface.
Emulsion dries in two stages: 1. water dries, 2. oil dries.
Emulsion of glue and vegetable oil is a mixture, in which the oil is in a liquid state.
Emulsions can be cooked from egg yolk. The yolk is mixed with water, chalk or dry white pigments are added.
Emulsion soils have a matte surface.
Glue soils.
They are prepared without oil. They consist of sticking, several layers of the base soil. Soil is prepared on the watered down solution of glue with the addition of plasticizer. Glue soil is always permeable.
On glue soils, paints are less likely to yellow and black down. These soils are quick to dry and do not require time lag. One of the best glue soils is caseic. It holds the paint well, and decreases detioration.
Casein - water-soluble glue. This is the most solid and reliable glue. It is well emulsified with oil.
Casein glue is easy to prepare. To do this you need 100 parts of low fat cream cheese, 4 units of the liquid ammonia. Squeezed cream cheese needs to be washed in warm water, then wipe through a sieve and mix with water. When the mixture is homogeneous, in the form of sour cream, add liquid ammonia. Mix to obtain a dense mass. The solution needs to settle for several hours, then re-mixed. The resulting glue can be diluted with water to desired consistency.
Soils
One-layer soil: 100 g of water, 5 g of sturgeon glue, zinc and lead white pigments, in equal shares. The solution is applied in warmed form. Drying time - 24 hours.
Double layer soil: 1 layer: for 100 g. of water - 5 g of gelatin and chalk. 2 layer: the same composition, but the solution is slightly thicker. After drying, buffing and soak for several days.
Synthetic soil
Prepared with synthetic binders: polyvinyl alcohol (PVC) and emulsion (PVA-EM) (polyvinyl acetate).
Polyvinyl alcohol (PVS) - dry, solid powder, without flavour, smell. Only water-soluble. Particularly resistant to the action of oils, fats, gasoline.
Polyvinyl acetate - solid, colorless, non-toxic substance, insoluble in water, gasoline.
PVA - EM - white emulsion. Does not become yellow, harmless. Compatible with paints, with exception of cobalt violet.
The structure and elements of paint color layer.
Each stroke of paint can have a specific form, size, direction. Texture of the color surface is an important means of artistic expression.
First method - undercoating, repaint, glazing.
Completion of work on each step must be accompanied by breaks for the full drying of the paint.
Undercoating is known as the first repainting of the painting basis with color. It is a preparatory stage. The main paint of the undercoating can also be white pigments. Undercoating in using the white pigments can also be multi-colored.
The next stage - in repainting - on a well dried undercoating the artist approaches the finished piece.
Glue soils are sometimes used with water color or tempera paints.
Tempera paints are applied in a thin layer on in extremely watered down state.
Method of Ala-prima
The peculiarity of the method is that the painting is done in a single layer. Method of Ala-prima is more suitable for sketches.
Cover layer
Complete picture is covered with varnish and other substances. First, the picture is cleared of dust, dirt.
Liquefier of paints
Oils - linseed or sunflower, varnishes (domar, copalic and others), thinners (purified turpentine, kerosene), etc. Turpentine evaporates when dried.
Liquefier 1 - a mixture of turpentine and white spirit, 2 - purified white spirit. Pinen - treated turpentine.
Brushes
Brushes can be bristle, badger, bear, etc.
Bristle brushes are the most rigid, in order for the bristle not to come out from the brush during painting, metal frame must still have some glue. After work brushes are washed with thinner 2.
Art with tempera
Tempera - an ancient painting technique. Tempera paints are a paste, easily dissolved with water. When dried tempera whitens, but does not glitter, it has a matte surface. Compared with oil tempera dries very quickly. Binders in tempera are the natural or artificial emulsions. Tempera has good technical ability. Thin painting with tempera is more preferable, i.e. the layer of paint when dried can crack.
Tempera is used without mixing it with other colors, or adding to oil, gouache, pastels, etc to it.
Paintings with tempera is sometimes covered with varnish of resin of domar, mastic.
Tempera is designed for mounted and decorative painting on canvas, cardboard, wood and other materials.
It is preferable to have a palette of plastic when working with tempera. Bristle brushes can be used.
Casein-oil tempera is a paste mixture of light-resisting pigments with emulsion, obtained through emulsification of linseed oil in water solution of casein.
Polyvinyl acetate tempera is prepared of fine mixture of pigments with water dissolved emulsion PVA, of a specific dispersion.
Half-oil soil
For glue-chalk soils, designed for priming the canvas, 4 percent glue solution is used, taking for 1 unit of dry glue, 25 parts water.
Glue-plaster soils for the canvas, are made on a 5 percent glue solution, taking for 1 unit of dry glue, 20 parts water.
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