Chapter 5: Surface Decoration

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Transcript Chapter 5: Surface Decoration

You are about to discover a vast number of surface decoration techniques and treatments!

The techniques you choose for your works are broken into 2 categories: Texture and Color

  Clay surfaces have historically served as a means for artists, to realistically or with abstract design, to: ◦ ◦ ◦ tell a story Display symbols of religious significance Beautify a form You can add texture ANYTIME before a clay piece is fired

 ◦ ◦ ◦ Stages of Clay: Plastic: soft and flexible Leather-hard: most water has evaporated from the clay, feels cool to the touch. Bone dry: Almost ALL water has evaporated from clay – feels dry and chalky to the touch.

 ◦ ◦ ◦ IMPRESSING- best done when clay is soft Press with a tool into clay surface and the mark left becomes a low relief of your tool Tool possibilities include: fingernail, button, stamping tool, textured wooden beater, string, rope, burlap, lace, or whatever your imagination leads you to You can make your own stamp designs in little pieces of clay!

 ◦ ◦ INCISING AND APPLIQUE- can be done at any time in plastic and leather-hard stage INCISING- cutting into the surface of the clay APPLIQUE- applying one piece of clay to another – pieces can be coils , cut-out pieces of clay, pads, or clay designs that are pressed on the SOFT walls of a rim or a form

  ◦ ◦ …continued…. Incising and Appliqué… Add these to the surface of your piece by using a little pressure If surfaces have dried somewhat – you will have to slip and score the pieces for better adhesion PIERCING and BURNISHING- should be done when clay is leather-hard

 ◦ ◦ ◦ ◦ Creates dramatic effects Tools can be knives, hollow cutting tubes, anything that punctures clay BURNISHING – rubbing the surface of the clay smooth with a stone or the back of a spoon Produces a shiny finish Burnish at the leather-hard stage

    Adding color to your piece opens up enormous creative possibilities COLORED CLAY- mix different colored clays in the same piece INLAYING- fill in impressed or incised marks with soft clay of a contrasting color OXIDES AND CARBONATES- what gives clays, glazes and underglazes their colors are minerals and metals

  ◦ ◦ COLORED SLIPS Slip is a mix of extremely fine clay with water Colored slip can be purchased to add to clay by painting or a dropper tool UNDERGLAZE – painting on the surface of greenware (or bonedry clay) before the first fire (bisque fire)

   ◦ ◦ SPONGING Vary from rough to smooth grain Give different textures and depth of color when daubed onto surfaces SPATETRING A toothbrush or a bristle brush can be used ◦ ◦ ◦ BRUSHING Paintbrush is good for blocking in areas of color or painting fine, delicate lines Can be used to finish details on top of a background, outline a design, or emphasize a certain aspect of the form

  ◦ ◦ ◦ MASKING Stencils can enclose or outline background shapes or foreground designs Cut out design from a piece of paper, lay the paper on the clay surface, apply color through the opening using one of the previous techniques Masking tape cut into lines or shapes also makes an effective stencil ◦ PAPER RESIST Cut shapes or patterns from damp paper and lay these shapes on clay surface

 ◦ ◦ ◦ ◦ WAX RESIST- use melted wax or white glue thinned with water - paint design on leather hard clay, then when wax is dry wipe away areas around it with a wet sponge. Top layers will melt away in kiln leaving a raised design Paint over waxed area with underglaze, the covered areas will remain clear and the unwaxed area will hold color Apply on bisqueware and it will resist any glaze that is applied Apply wax details OVER a glaze, brush or dip another glaze over it, or carve away areas of waxed area and apply glaze to the exposed surfaces

  ◦ SLIP TRAILING- squeeze a line of slip onto damp clay to produce a raised line Slip trailers can be made from pastry bags, mustard dispensers, rubber syringes SGRAFFITO- scratching designs into colored slip or glaze to reveal the clay body underneath

  MISHIMA – a pattern or design is incised or carved into the clay, slip is brushed on and then once dry – scraped off the raised areas so only the incised carving has the color TERRA SIGILLATA – exceptionally fine-grained clay suspension in water, similar to colored slip

    Transfer Printing – using etched plates Monoprints- a single print Photo Emulsions Computer Generated decal Transfers – using an image printed to transfer to surface of clay

  Glaze has the same characteristics as glass when it melts and fuses onto a clay surface All glazes made from 3 basic ingredients: silica, flux and alumina

   ◦ ◦ Low-Fire: The First Glazes (what we use!) Melt a relatively low temps High-Fire Glazes ◦ Used on stoeware and porcelain ◦ Must be fired at high temperatures Overglazes and Paints A low temperature glaze that goes OVER original glaze

   Clean pottery – wipe it with a damp sponge or rinse it quickly under the tap - dry Paint wax on (if using) May have to paint several layers – test thickness by scratching glaze with thumbnail. Should be the thickness of a card.

    Dipping – dipping glaze into large container filled with glaze Pouring- pour glaze inside piece and swirl around, pour out any extra back into glaze container Brushing – use a SOFT paintbrush to apply glaze ◦ ◦ Brush at least 3 layers onto piece in DIFFERENT directions Do NOT allow glaze to dry out before adding layers Spraying- using a spray gun or an airbrush to apply base glaze