TASC Art Studio Practice cheat sheet

Art Studio Practice: Materials, Safety, and Process

• Pigment is the colorant; binder holds pigment to the surface; solvent thins or cleans. Oil paint uses drying oil (linseed, walnut), acrylic uses acrylic polymer emulsion, watercolor uses gum arabic, tempera uses egg yolk.

• Oil paint dries by oxidation and can be applied over dried oil, but acrylic should not be applied over oil; oil over acrylic is acceptable only if the acrylic is fully cured, because flexible-over-rigid layering causes cracking.

• Fat over lean: each successive oil layer should contain more oil (more flexible, slower-drying) than the layer beneath, preventing surface cracking as lower layers dry and shrink.

• Watercolor is transparent and relies on the white of the paper for highlights; gouache is opaque watercolor with added white or larger pigment load; acrylic can be used opaque or thinned to a wash.

• Solvents: turpentine and mineral spirits thin oil paint and clean brushes; they are flammable and volatile, so ventilation and closed containers are required. Water-mixable oils clean up with soap and water.

• Dusts from sanding, clay, and dry pigment are inhalation hazards; silica and some pigments (e.g., cadmium, cobalt, lead white) are toxic, so wet methods, local exhaust, and gloves are preferred over dry sweeping.

• Brushes: natural hair (hog bristle, sable) suits oil and acrylic; synthetic filaments suit acrylic and watercolor; wash watercolor and acrylic brushes with soap and water, oil brushes with solvent then soap.

• Drying times: acrylic films dry in minutes to hours and cannot be re-wetted once cured; oil films skin over in hours but fully cure over weeks to months; watercolor remains re-wettable.

• Storage and disposal: keep solvent-soaked rags in a closed metal container because spontaneous combustion can occur; never pour solvents or pigment sludge down the drain; use labeled waste containers.