A ready-to-use primer in a non-yellowing oil-modified alkyd resin medium. No thinning or stirring is required. Oil Painting Primer can be applied directly to metal or porous surfaces (glue-sized canvas, untreated wood, hardwood, plywood, paper) with virtually no sinking in. A small amount of oil colour can be mixed into the Oil Painting Primer for tinted priming. The treated ground accepts oil colours easily and without chalkiness or absorbency. Although Oil Painting Primer dries quickly, a 24 hour drying period is recommended for each coat ? most grounds will always need two or three coats of primer, which should be applied around edges and on the reverse of the surface to prevent warping.