To prevent warping it is recommended that you fix an armature (stretcher-like square) behind to give it some stability.

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1 Materials Supports and Grounds. SUPPORTS Panels Plywood Hardboard MDF Can be light weight, but the thinner the material the more it will be subject to warping. Also bear in mind how heavy a large board will be to manoeuvre, MDF is not recommended for archival reasons (it is very acidic and unless prepared correctly will deteriorate), and due to health concerns you are not permitted to cut the boards in the College workshops or studios. Marine Ply is one of the most stable boards to use as a painting surface, it is water resistant but expensive. To prevent warping it is recommended that you fix an armature (stretcher-like square) behind to give it some stability. Metal Plate Copper Aluminium The main advantage of this material is that it does not warp, is very strong and lightweight, and resists sagging. Unlike copper, which reacts with the linseed oil in oil paint and turns green, aluminium is relatively inert. However, an aluminium surface that is polished is not as good a support and must be de-greased, sanded and then etch primed (U.POL Etch Primer) Although all metal supports can be painted on with out sizing or ground, the surface of aluminium must be completely covered with paint or protected with a varnish. If this is not done, the moisture in the air will react with the aluminium and over time will result in corrosion. Linen Canvas (there is polyester canvas too) Card - Paper

2 Before painting all these surfaces need to be prepared in some way. As a rule Oil paint will over time, degrade an organic painting surface, and you will have to take some time to prepare and protect the canvas etc. you will be working on. Acrylic paints are not going to cause such damage, but it is equally advisable to take as much care in preparing your support. SIZE What is Size? Traditionally, a size or animal skin glue (rabbit-skin) is applied directly onto canvas or linen to stiffen the fabric and protect the support from the acidity of linoleic acid in linseed oil used in oil paint. The traditional method of sizing a canvas for oil paintings involves the use of a hide glue, such as rabbit-skin glue. 1.Soak the glue in water one part glue to ten parts water for twelve hours or until the crystals swell. 2.Heat the mixture gently in a double boiler to about 80 C. If the glue is heated too quickly or brought to a boil, it will become an unusable gelatinous mass. (After the glue has liquefied it can be filtered through cheesecloth). Allow the glue to cool to about 60 C. 3.Then apply it with either a brush, spatula, or palette knife. Be sure to work the glue into the canvas. This will fill any pin holes. Sizing Canvas For Oil Paints Oil painters must size their canvases to stop the acidic oil from penetrating into the support, which, over time, cause the fibres to rot and become brittle. The purpose of the sizing is to seal the fibres of the canvas, not to provide a continuous, solid paint film. If too much glue is applied, cracking will result. Sizing Canvas For Acrylic Paints Acrylics are inert and can be applied directly to canvas without sizing. Although sizing is not needed to protect a support from acrylic or emulsion paints, it can be used to reduce the absorbency of the support because, if too much of the paint sinks into the support, the colour loses its intensity and develops a dull appearance. Sizing Paper. The sizing used by the manufacturer of paper and board to produce a specific working surface should not be confused with the sizing needed for paintings with oil or acrylics.

3 When producing artwork, it is safe to use acrylic paints directly on unsized paper or board. Using oil paint directly on unsized paper or board will result in self-destruct artwork because the acid from linoleic acid of linseed oil in oil paint breaks down the cellulose of the paper, and the combination of the two provides an ideal environment for the growth of mould. To prevent this kind of damage to the paper fibres, they must be coated with a size. Rabbit-skin glue, is one of the oldest and most reliable substances used for sizing paper and canvas; the preparation of and application to both supports are very similar. The only difference is that for paper a 3 percent solution (one part glue to thirty parts water) is used and two thin coats are applied. Sizing Panels. Wood, or wood-product panels, such as plywood, particle board, and fiberboard, should be sealed with a wood sealer. Modern wood sealers reduce the wood's absorbency and help to preserve and protect it-desirable qualities of a size. Consequently, a wood sealer can be used as a size for panel supports. Animal skin glue Size is not appropriate as if it is used the grain of the wood will swell and rise, requiring sanding to make the surface smooth again. Panels made of metals, such as aluminium, are not absorbent and do not have to be protected from the paint, hence sizing is not necessary. PRIMER A primer is a coating that prepares the surface for the acceptance of paint. There are a wide variety of primers especially designed for different paintable surfaces. So it is important that you select the appropriate primer compatible with the support and paint you are using. Use a primer that adheres well to the support, as well as ensuring that it offers adequate adhesion for the subsequent paint layers. Alkyd primers are well suited for increasing the adhesion of paint to metal. Auto primers are often used for sprayapplications on metal surfaces. Acrylic Gesso Acrylic Gesso is an excellent primer for most natural painting surfaces such as canvas and wood. You get what you pay for and student grade gesso will not be as flexible or opaque as some of the more fancy options, GOLDEN/LIQUETEX /LASCAUX ETC. but don t worry too much at this stage, use what you can afford.. Sandable Hard Gesso contains solids that facilitate sanding, but is limited to more rigid supports to lessen the chance of cracking when flexed. Acrylic Gesso can be used for acrylic, watercolour, tempera, gouache, casein, alkyd and oil paints.. Using Mediums as a "Clear Gesso"

4 Even when an artist intends to have the support show through, you should apply some sort of medium to the surface. This allows for protection of the support, and may be important for adhesion of paints to the support as well. GOLDEN/LIQUETEX /LASCAUX ETC Fluid Matte Medium, Matte Medium or GAC 100 (for acrylics) will all work well as clear "gessos" to allow the look and texture of the canvas or other support to show through. GOLDEN/LIQUETEX /LASCAUX ETC Fluid Matte Medium and Matte Medium will result in a clear and matte surface, while the GAC 100 yields a glossy finish. Thin washes of paint for stain applications will be altered by the use of any primer. Therefore, the artist can get proper film permanence by allowing the stained canvas to fully dry, and then apply the clear "gesso" over it, sealing off the canvas. APPLICATION OF A GROUND A ground is a surface specially prepared for painting by applying a layer of paint of even tone in preparation for further painting techniques. Health and Saftey Materials and Safety Used solvent can be reclaimed by allowing the paint to settle and then pouring off the clear solvent. Paint can be removed from your hands with baby oil, and then soap and water. Do not eat, drink or smoke when working due to the risk of ingestion (swallowing). Avoid excessive skin contact, particularly with solvents. Do not point your brushes in your mouth; paints are not made for human consumption. Use a barrier cream, like Winsor & Newton Artguard or surgical gloves when painting with your hands. When airbrushing, wear an approved mask and work in adequate ventilation to avoid inhalation of airborne particles. An exterior vented extraction system is recommended. When using powdered pigment, wear an approved mask and work in adequate ventilation to avoid inhalation of airborne particles. An exterior vented extraction system is recommended. Wet mop and wipe all surfaces when using dry pigments.

5 Do not pour out more solvent than is necessary for your current painting session, it will only evaporate into the room. If paint or solvent is splashed into the eyes or on the skin, wash thoroughly with water. Avoid prolonged inhalation of solvent vapours. Clean up all spills.