Sculpture

With the term sculpture we define the art and the technique of representing by removing, and also the final product, any three dimensional object created as an artistic expression building, cutting or modelling different materials.

The specific characteristics of sculpture are the real development of the three dimensions height, length and depth, that is effective three dimensionality, the potential of the material, marble, stone, wood, ivory, bronze in its spatial dislocation, the dynamic relevance of light in the creation of spaces and fillings.

Sculpture techniques are substantially: carving and modelling.

Carving is carried out on hard material like marble, stone, etc. using sharp or cutting tools, splinters, scalpels, punches, drills, scrapings, files, staples, etc..

Modelling is carried out freehand or with the help of instruments like spatula, sticks, burins, mirette, burette, etc. on malleable materials like wax, plasticine, clay, plaster or stucco with the aim of obtaining embossed figures. It is possible to model an object by addition or subtraction. Materials like wood, marble, etc. can be worked cutting and sculpting the same material, taking away some parts, penetrating a block of material and carving inside it. Plastic materials like clay on the contrary can be modelled both adding and taking away material.

“360 degree” sculpture is a plastic representation in three dimensions, completely modelled on all sides, observable from every point of view.

Low relief removal or “basso rilievo” is a plastic realisation in which part of the material removed emerges slightly from the bottom surface. The high relief removal or “alto rilievo” results in a cross between 360 degrees and low relief removal, the figures, placed on a base, are perceptible only from the front and side, even if the depth, that is the parts that emerge from the volumes modelled, are very evident.

The sculpted surface of the finished work, is perfected with different techniques: polishing, smoothing, ammaniatura, polychrome.

Modelling at 360 degrees

Wet clay is one of the most commonly used materials for modelling, you can work easily with your hands or with the help of particular tools, amongst which wooden sticks, plastic sticks or mirette, tools equipped with irons adapted for carving and extracting clay.

Overall, you work by adding pieces on shaping with the hands or with the sticks.

If the work at 360 degrees is of considerable dimensions, it is necessary to build a support scaffolding, which may be made from an iron base folded in the correct way or by a piece of wood or other rigid light material.

During the manipulation, the clay must not dry, for this reason the work, between one sitting and another, must be kept damp covering it with a wet cloth, and wrapping it in plastic sheeting. When the work is finished and the clay is dry it must be baked in special kilns at a high temperature: that's where the name “terracotta” comes from.

Bronze fusion

Some sculptures are obtained indirectly, that is the initial figure is modelled in clay, wax, sand or plaster and then transferred by means of “fusion” in bronze, a metal alloy formed essentially from copper and tin. The technique of fusion has the aim of reproducing a figure in a more enduring material than that from which it was originally modelled, or to obtain several copies. Two ways of using this technique exist: direct and indirect.

In the direct method a wax model is created to be used to make a mould in clay. Making two holes in the mould, one at the top and one at the bottom the wax exits heating it and fused bronze is poured in to replace it. An identical model to that in wax is obtained.

In the indirect method, the wax model is realised above another in clay in a way that the final statue is empty inside, or better, contains only clay to limit the weight and quantity of the metal used.

The creative phase of the work consists in creating a draft of wax in scale, to follow as a guide. Secondly, a model in clay is realised in the final dimensions, that is the soul or anima, which is baked becoming terracotta and shrinking. On this a layer of wax is lain that recreates the definitive dimensions of the work. Tubes of various dimensions are applied in wax segments to the anima covered in blowholes, with nails as support. On this "porcupine" structure another layer of clay is lain, the so called shirt or camicia, from which the blowholes for the melted wax emerge.

The model thus prepared is baked again so that all the wax might melt and become fluid. The heat transforms the shirt or camicia into terracotta and the presence of the support nails allows the creation of a cavity where the fused bronze is glued.

Before proceeding with the final casting the whole work is covered with bricks, creating the so called fusion cloak or cappa di fusione, reinforced with ties and iron plates. The cloak is lowered into a predisposed hole under the oven opening from which the fused bronze will be poured. The bronze, entering into the cavity, forms a print, which has the same thickness as the wax eliminated.

Once pouring has occurred, the cooling takes place, the mould is taken out and refined.

The liquids from the metal are taken away and eventual defects from the fusion are eliminated; sometimes the work is completed smoothing the surface or in silver or gold.

Ceramics

Ceramica in Greek means clay. Working in ceramics means then working in clay, and fixing the desired form by means of a final baking, terrecotta.

Clay is found in natural sediments and varies in quality and colour. Natural clays, are mixed with other components to create pastes with different characteristics for hardness, colour, porosity, plasticity, points of baking, etc.

Sweet earthenware is a paste that becomes white after baking, and is used for the production of objects.

Terracotta is a particularly plastic paste and adapted to modelling. After baking the colour varies from red to brown; it can be refined with paint or, using its natural colour, engraving or rendering its surface rougher, decorations can be created which use the contrasts of light and shade on the surface. This paste is used to obtain models from which a mould can be made. The refractory paste has the characteristic of resisting high temperatures. To this amalgam a filler or “chamotte” is usually added, a mixture that increases the porosity and consistency. It is adapted to realising large sculptures.

The porcelain paste presents a white and smooth hard and impermeable surface after baking. The paste has the characteristic of shrinking about 20%, with baking making it adapted for the building of objects such as statuettes, which are first modelled in red clay to such a size so as to be able to work easily to obtain a plaster mould in which you will be able to throw pieces which, after baking will have shrunk maintaining all the particulars right down to the minimal details.

Liquefying the clay in water and a substance that helps the fluidity you obtain the throwing or barbottina, a fluid paste with which shaped objects shaped in plaster moulds can be created; the water contained in the barbottina is absorbed by the walls of the plaster mould into which it has been poured, layering the clay; emptying the excess fluid when the consistence will be such that allows it to hold itself upright, an object obtained so, will be able to be extracted from the mould, refined with a small scalpel and smoothed with a wet sponge.

In the pressing technique in a plaster mould on which the negative print of a relief is, quite a thick layer of clay is overlain and pressed with the fingers proceeding with pressure from the centre towards the borders; the piece obtained may be extracted by pulling and lifting from one side. One of the most simple techniques, adapted for creating objects with the greatest freedom of expression, is called wick lucignolo or dove colombino. You start with a sheet of clay from which the base form is cut, then cylinders of clay (colombini) are applied on its perimeter, enabling the adherence with a light pressure of the fingers. While this is done, form is given to the object which could be rounded, cylindrical, countersunk, conical etc. the finished object can be smoothed with a steel or wooden laminate and, when it is finally dried, it can be further smoothed with sand paper and rendered even with a damp sponge.

Lathe modelling is generally used for the production of objects with a symmetry with respect to their axis of rotation. The lathe is made up of a revolving base whose speed is regulated using a pedal, or a motor. A certain mass of clay is placed at the centre of the wheel, and the modelling begins.

When the work is finished you proceed to the drying and then to the baking. The clay passing from its wet state to its dry state, experiences a reduction in volume and weight, the shrinking ritiro, which varies from paste to paste. After the first baking the clay or the ceramic paste, take the name biscuit. There are many ways of decorating and colouring the ceramics, also in relation to the type of result that is desired and the baking which it is subject to.

Engobes are the colours obtained with dried clays then mixed with water and finally sifted so as to obtain a dense liquid. This barbettina of white or coloured clay is applied to objects in clay in the “leather state” (dried objects, but still raw and requiring baking); after you proceed to the drying and baking.

Crystalline or glaze, are glass powders that dissolve in water. The mixture obtained is lain out on the biscuit, in a very thin layer, immersing the object or spraying it with a spray gun, after which a second baking follows. The crystalline sinks and becomes glassy, bright and transparent or even coloured.

The decoration under crystalline, is the real and true decoration phase. The colours go directly to the biscuit, which can be white or red. For the method decorating by paintbrush the well mixed colours are applied with the paintbrush moving from the lightest to the darkest. Ready to use colours or pigment powders that must be dissolved in water can be found on sale. After having drawn and coloured the piece, an essential phase follows: that of glazing using crystalline.

Pencils for drawing ceramics are used like normal coloured pencils. In the sponge decoration, a small sponge is immersed in the colour dissolved in water, then slightly squeezed and dabbed over the parts to be coloured.

The glazes that cover the biscuit, these too glassy, are coatings which are shiny and satinised. After the baking, the result will always be that of a hard and compact covering that will render the object completely impermeable.

In the majolica technique, you start with the red biscuit on which a layer of usually white glaze is applied. Once the glaze is dry, the decoration is realised with the use of colours, then you proceed to the baking. The effect is similar to that of water colour painting, the colour is light and it allows the clear underlayer to show through.


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