Oil pastels can be used alone to create a painting. Apply them thickly or thinly, blurred or clearly defined. They can be combined with oil painting mediums such as turpentine, paint thinner, or any of the painting oils to produce glazing, scumbling, or wash effects.
Oil paints should never be used over oil pastels, because oil pastels never dry out, and oil paints will not adhere to the underlying surface. Oil paints can be used over an oil pastel wash, provided that the underlying surface is primed. Interesting effects can be achieved by scraping, scratching, smearing, or scrubbing the pastel surface.
Oil pastels can be used as a resist with water-based mediums such as watercolor or acrylic. Waterbased paint will not mix with the pastel. Oil pastels can also be used with colored pencils and oil sticks. They can be used in conjunction with printmaking inks to create monotypes.
Oil pastels can be applied with a palette knife to achieve impasto effects. For ease in application, the pastel can be heated or melted to obtain a smoother, more creamy or fluid medium.
Recommendations for Supports — Sennelier Oil Pastels were created to free artists from technical restraints and the limitations of traditional supports such as canvas. They are extremely versatile and can be used on a wide variety of surfaces.
Use them on acid-free drawing paper, at least 100–110 lb. weight, or on watercolor paper, at least 140 lb. A surface that is lightly textured, but not rough, is customary for oil pastels.
Use them on museum board, illustration board, or any acid-free paperboard stock, or apply them to rigid supports such as wood, Masonite, glass, ceramics, or metal.
Soft supports such as canvas, made of cotton, linen, or polyester, can also be used, as well as other natural and synthetic fabrics.
Note — Although it is not absolutely required, Sennelier recommends applying a coat of gesso prior to painting on non-paper surfaces, to preserve the intensity and vibrancy of colors.