Rub-off techniques add new dimensions to your oil painting.
Oil paints, with their varied drying times and blending capabilities, give you many options when working on a new art work. Rubbing off techniques allow you to add layers of paint and then rub or wipe them off to reveal the color underneath. These techniques work well when you try to add shadows, dimensions and texture to a painting. They can be used on traditional canvas or on boards. Get comfortable using these techniques so you can add to your repertoire of painting skills.
Single-Color Rub-Off
Single-color rub-off paintings resemble black-and-white photos because the contrast is made using shades of just one color. Burnt umber is a popular color to use for single-color rub-off paintings. Cover a canvas with one color of oil paint, and then, while the paint is still wet, remove the color starting with the lightest portions of the painting with cloths or brushes. For example, if you are painting a portrait, the lightest portions of the painting would probably be the whites of the eyes and the teeth. To give the painting texture, use a variety of tools to remove the paint. Effective tools include rags, paper towels, palette knives and flat paint brushes.
Rubbing Out
The rubbing-out painting technique was used prior to Michelangelo's time, but many artists still use it today. To paint with this method, first completely cover your canvas or board with linseed oil and then wipe off the excess with a rag. Sketch the outline of your image on the canvas with a #4 sable brush and a mixture of paint and linseed oil. In a shallow bowl or on a palette, mix 75% burnt umber with 25% raw sienna, which slows down the drying process. Leave the paint mixture to in the open air for about 4 hours, then add a drop of olive oil to the mixture and work it into the paint with a palette knife or a stiff brush. Use a rag to apply the mixture to the canvas, and smooth it out with a bristle brush. Cover the ball of your thumb with a rag, and use it to rub out areas of the painting that you want to be lighter. Lay the canvas or board on the floor and spatter mineral spirits on it. Allow the canvas to dry for at least 2 days before applying a glaze.
Dead Layer
Dead layer painting is a method of introducing shadows by rubbing out a gray layer. Mix 2 parts black paint with 1 part burnt umber and 1/8 part ultramarine blue. After you have painted your main images, paint the gray layer over your painting. Start with the darkest grays around the outside of your image. Next, lighten the gray on your palette by adding some white, and add this lighter gray over your image. You can even lighten the gray one more time and make a very light gray section in the middle. Blend the grays together, and wipe away as much as you need to in order to preserve some of the gray shadows while seeing the image underneath.
Detailing
When you have applied a darker color over a lighter color, rub off the darker color with a cotton swab or an ox-hair brush for gentle detailing. You can always go back and harden up edges of your painting by adding more color if you rub off too much paint. Try applying several values of a color to give your painting dimension and then rubbing off as much as is necessary to show those under-values.
