Saturday, August 19, 2017

Is Gesso a Good Primer for Painted Rocks?

Yes, in my opinion gesso is an excellent primer for painted rocks.



Gesso (pronounced jes-oh) is used to prepare a canvas for painting. (If you would like to know more about gesso, this article "What is Gesso and How is it Used in Painting?" is very informative.) 

I've been hearing about gesso used to prime rocks (my canvas) and thought I'd give it a try instead of the usual white, acrylic paint.

For my experiment, I purchased two types of gesso from the Michaels.com website...
  • Regular - Folk Art brand
  • Super Heavy - Liquitex brand

...and selected a smooth stone for the regular gesso and a pitted stone for the super heavy gesso.

My process:
  • Brush one coat of each type of gesso on a stone (regular gesso on the smooth stone, super heavy gesso on the pitted rock)
  • Paint the same design on each stone using one coat of various brands of acrylic or acrylic craft paint
  • Use an art pen for thin details
  • Seal the stones

Gesso features and performance:
  • Folk Art - regular gesso
    • Consistency of toothpaste
    • Applied with a brush easily and smoothly
    • A little went a long way
    • Covers well
    • Can be mixed with acrylic paint for a colored base coat
    • Soap and water clean up
    • Quick drying
Regular gesso applied to a smooth stone

  • Liquitex Super Heavy gesso
    • Consistency of cake icing or spackling compound
    • Somewhat messy
    • Applied with a brush and required smoothing in different directions
    • Can be tinted with acrylic paint
    • Soap and water clean up
    • 24 hours to dry
    • Brighter white than the regular gesso
Super heavy gesso applied to a pitted rock


Paint colors and brands used:
  • Craft Acrylic (craft acrylic is a thinner consistency than regular acrylic paint)
    • Anita's Orange
    • Anita's Christmas Green
    • DecoArt Cherry Blossom Pink
  • Acrylic
    • Americana Snow (Titanium) White
    • Apple Barrel Bimini Blue (turquoise)
    • Apple Barrel Red
    • Apple Barrel Lime Tree
    • Apple Barrel Black
    • Folk Art Sky Mist (light blue)
 
The acrylic and acrylic craft paint colors adhered very well with both types of gesso. The brush moved smoothly across each rock's surface.

Results of one coat of paint applied over each type of gesso

There were no problems using the art pen on the gessoed and painted stones. In fact, the pen drew especially well on the pitted stone primed with super heavy gesso.

Results of art pen used on gessoed and painted stones (Sehnaz Bac design with permission)

My final photo clearly illustrates the benefits of using white acrylic paint or gesso as a primer for a stone. The paint colors on all three primed stones are brighter than the unprimed stone. The difference is most apparent when you compare the orange hue on each painted rock.

Results of no primer vs. acrylic paint and gesso primers (Sehnaz Bac design with permission)