Tip: Preparing a Smooth Finish for Painting

Some painters find commercially finished canvas too rough for detailed painting. Similarly, hand finished boards can have a texture that is either too rough or not consistent. Here we will discuss how to make a canvas or board smooth enough to paint on without sacrificing grit or interest.

Purchased canvases have already been prepared with a thin coat of primer. If you like a coarse woven texture, you don't need to do anything more. However, in order to obtain a smooth, flat surface, priming with additional layers of gesso will help you achieve the desired affect.

Real gesso is made of rabbit skin glue and calcium chloride (or chalk). Titanium white and marble dust may be added to give it a lighter pigment and thicker consistency. Acrylic gesso that you can find in most art stores is something different. It is a combination of calcium carbonate and acrylic polymer latex. Acrylic gesso is flexible enough to use on canvas where real gesso is not. Real gesso should only be used on stiff boards.

Most gessos are very thick and can be diluted if they are too difficult to work with. Just be careful not to add too much water (no more than 1 part water to 2 parts gesso) as you might compromise the integrity of the polymer. Fillers can also be added to the gesso to give the surface a little character (such as, sand, crushed rice, or marble dust). Stir the gesso mixture until it is smooth and a uniform consistency.

Gesso is built-up in multiple layers depending on the smoothness desired. With each application, coat the entire surface including edges and corners. Work the gesso into any surface gaps (such as, between the weaves of canvas). Gesso dries rapidly so it must be applied in quick even strokes.

Gesso can be apply with a standard paint brush, roller, or sponge. If using a brush, each layer must be applied entirely in the same direction while subsequent layers are brushed in an opposing direction (for example, first layer vertically, second layer horizontally, third layer diagonally, and so on). For a very smooth surface use a foam roller to apply the gesso. The lighter the pressure the smoother the surface. For a rougher texture press harder with a foam roller or use a standard paint roller.

Allow the gesso to dry for 30-60 minutes. Rinse your brush, roller, or sponge between applications as gesso is hard to remove when dry. For a completely smooth texture, sand the surface using 100 grit sandpaper. Then dust the surface with a lint-free cloth to remove any loose particles. Repeat this process for as may layers as desired.