Not a few artists recommend wet sanding a canvas or ground before painting an artwork on the medium as a preparatory step in ensuring smoothness of a surface.
The technique is usually recommended when gesso or a coat of paint is applied as background. While waiting for the ground to dry, dust could accumulate and stiffen on the surface. Such flaws become noticeable only when subsequent applications of other paint colors become difficult to spread or blend evenly on the affected area.
However, when following this preparatory technique, there are some important aspects to take note of, in order to achieve the right results.
Things to Consider When Wet Sanding a Ground
Ground, which is short for background, is the initial layer of paint applied on canvas, paper or wood. It can either be covered with other paint medium or left visible in the finished artwork.
It’s important to take note that there is a specific type of sandpaper for wet sanding purposes. Sometimes called waterproof sandpaper, waterproof abrasive paper or in some cases wet-dry paper, it’s specifically used for smoothing out a surface rather than for contouring. When wet sanding a canvas or ground, use a waterproof sandpaper because its paper backing, even when wet, is not likely to diffuse color that could interfere with the surface paint.
Use a 150 grit or higher, up to a middle ground of 220 wet sandpaper, while sanding with light, circular motions and occasionally spritzing water with a spray mister. The importance of sanding with circular motions is that the technique avoids rubbing abrasive material on any one area repeatedly. Doing so with vertical sweeps could result in over sanding, which could make the canvas or paper turn brittle and later cause the subsequent color media to crack.
If you’re to wet sand a larger surface, let’s say a wall for a mural art or to custom paint the body of a car or motorbike, consider using a dual action sander (a.k.a da sander). Since a larger area will be wet sanded, using a powered sanding tool will make the process less tedious and faster to accomplish.
Moreover, a dual action sander is versatile to use, as it allows switching between wet sanding and polishing a paint coated area in circular or orbital motions. That way you’ll be painting on an ultra smooth wall surface on which to paint a mural, or a car body part on which to airbrush customized artwork.
If you want to know more about dual action sanders, checkout this review webpage, as the info provided can also help you identify the best da sander to use for art projects.