When I want to know things I tend to go to the bottom and gather knowledge and experience from different sources. Then I try out the facts/statements in my own practice. For me it’s important to not just know how things work, but also why.
So now I have painted with encaustic for some time and feel I have pretty much a good picture of the basics. In most areas, except one. A discussed topic with a lot of different opinions. I guess tradition is interfering with new approaches. Good old facts are challenged by new science. And who’s right?
What types of Gesso are suitable for Encaustic Painting?
As I wrote in the title, I want to know what types of gesso are suitable for encaustic painting. R&F has done an excellent review of this. You can read the whole report here:
But the short summary is that they used the often referred to “freezer test” to determine what substrate is suitable for encaustic painting.
You may wonder, if R&F has already done this, why am I conducting my own test? Well, I wanted to try out three grounds that R&F didn’t test.
- Casein gesso?
- My own acrylic gesso?
- Water colour ground?
Casein is what I mostly use and a lot of other encaustic artist as well. I wanted to be sure before I sell paintings that I state facts I know I can stand for.
A somewhat hot subject to enter in the world of encaustic. Let me assure you, I have had a conversation with R&F about this topic. R&F encaustic gesso is an acrylic gesso. R&F claims that acrylic is not just good but excellent as an encaustic gesso, IF you understand the chemistry behind it…
“What is missing in this common assumption about acrylic is an understanding of the ratio of binder to solid.” R&F Handmade Paints
This made me ask R&F what they thought of watercolour ground, an acrylic ground with a lot of absorbing material in it. R&F told me to try it.
I then asked about a homemade recipe of watercolour ground with acrylic and marble dust (calcium carbonate). And they answered again that I should try it. R&F encourages artists own experimentation. They also encouraged me to post my results. So here I go.
Preparing Grounds for Testing
I prepared a plywood surface with four different types of gesso grounds.
- R&F encaustic gesso (as a test reference)
- Watercolour ground (Daniel Smith)
- My own acrylic gesso (2 part cheap white acrylic paint and 1 part calcium carbonate)
- Casein gesso (Sinopia)
The Freezer Test
- Following R&F’s tips, I let the painted board rest until the next day.
- Then I painted each with my own encaustic medium (1:8 ratio) four times, fusing in between of course.
- I put the test boards in the freezer for about an hour. (By the way it didn’t crack in the freezer.)
- Back to room temperature for at least four hours.
- And then SLAM. Hard. Really hard. Four times on a concrete floor.
Not a mark. The encaustic was stuck solid hard on the board. On all four surfaces.
Then I scraped the surface and even gouged the wax loose hard with a screw driver. Same on all four surfaces. Really good adhesion. I didn’t proceed with all the steps R&F did in their test, this was enough to convince me.
So I can’t of course say anything about how acrylic encaustic gesso will perform after 50 or 500 years but that it works right now is beyond my doubt.
Try it yourself
Please copy my test and try it yourself. Then please post your results in the comments below.
If cheap acrylic paint with some pretty cheap marble dust (calcium carbonate) can make a good ground for encaustic, a lot of poor encaustic artists will sing out loud. Hurray for science and art!