Gesso is used to prime your canvas before painting. You can buy gesso ready made from any art supply shop. It is very similar to white acrylic paint and helps to create a firm painting surface. You can apply it to any surface, and then you can paint on that surface with acrylic paint.
Types of Gesso
Gesso is normally white, but nowadays, you can also buy black, clear and coloured gesso. It comes in tube, bottle and buckets. You can make tint gesso by mixing small amount of acrylic paint to the gesso, adding variety to your gesso.
Gesso also comes in artist grade and student grade. The difference between the two grade is the ratio of the pigments and filler it contains. Student grade is cheaper compared to artist grade because it contains more filler than the artist grade. Artist grade has more pigment than student grade, making it more thicker and opaque. The consistency and texture of gesso vary from brand to brand. Some are more fluid, and others are thick.
Why We Need to Prime the Surface?
Most pre-stretched canvases are pre-primed, that means you can start painting with acrylics directly from the packaging. But in some case, you may feel lack in absorbency and in smoothness. So, it is advisable to give the canvas another coat of gesso.
To apply gesso, use a large brush or sponge brush. If the surface is bigger, you need bigger brush.
Dip the paint brush into the gesso and brush it onto the wood /canvas. Paint a thin layer of gesso to the entire surface evenly. That’s it. If you want to apply further coats of gesso, then make sure that the previous coat has dried completely to get best result.
(If the gesso is too thick you can dilute it with a bit of water. It makes the surface smoother. If you want a textured background you can leave as it is.)
For Canvas, you only need 2 to 3 coats of gesso but for wood you need to process further by sanding. In case of wood, using sandpaper, gently sand. Make sure the surface is completely dry before sanding. You can do the priming process (applying gesso and sanding) 2 to 3 times depending on your preference.
How to make crackling effect?
After priming the canvas/wood, apply acrylic color of your choice (most preferably use a color contrasting to the applied gesso color to get best result). For e.g. here I used black acrylic color as I used white gesso. Paint a thin layer of paint and let it dry.
Apply layer of crackle medium over the surface that you prepared in step 1.
For larger cracks apply a thicker layer of crackle medium. Allow the applied surface to dry for up to 12 hours (based on the drying time of the used crackle medium). Once the surface is completely dry, use a soft brush to apply a thin coat of paint.
Use a color that is contrasting to the base color created in step 1(e.g. I used white color on my black base) Do not over work the surface in order to avoid reconstituting the medium and blending with the paint. Thats it! You will see the crackling effect immediately as shown in the image.