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John S. Priddy
03-12-2000, 09:17 AM
I was working on an acrylic painting with the background completed. I made a charcoal drawing, sprayed it with water, and when I wiped it off, some of the background came with it. I tried another spot, and the same thing happened. The background had dried overnight, and had to be dry. I was painting on a gessoed canvas that had been painted and gessoed over 2-3 times. I was using Liquitex High Viscosity Artist' Color, on Liquitex Basic Gesso.

Does anyone have any ideas? I thought acrylic were basically indestructible, once they had dried.

Drew Davis
03-12-2000, 11:20 AM
The first two things that spring to mind: you say that you were working on a canvas that had been gessoed and painted over 2-3 times. If, by "painted over", you mean a complete painting, what sort of finish did you have on it? Not all acrylic provides good adhesion for higher layers. (That's why gesso is gesso, and not just white paint, and why some people have had bad experiences with acrylic underpaintings for oils.) The hard varnish types tend to be meant to seal things out, and that includes other paint layers. The other thing that occurs to me to ask is how thin your background was. If you dilute acrylics extremely in a wash, you can get to a point where there's not enough polymer to form a film, and instead you just have pigment and plastic dust stuck to your surface.

John S. Priddy
03-12-2000, 10:29 PM
Drew, I guess I should have explained that the canvas had 3 acrylic paintings on it prior to this one. Each one was covered with gesso after I "gave up on it". I once heard an instructor say you could do this to a canvas several times. The surface was smoother than I was accustomed to. I suspect you've hit the nail on the head. I guess after a couple of practice paintings on one canvas, that should be it. Let me know if there is a way to use a canvas several times for practice.

CarlyHardy
03-13-2000, 04:39 PM
John, one of the things I do, when doing a study or a practice piece, is to work on watercolor paper. I have large board with a clamp on one side...clip the paper to the board and put it on the easel. Paint just as I would on canvas. These later become parts of larger works or get torn into smaller shapes for collage work or get cut into smaller sizes, matted and framed as an abstract.
I like the rough, cold press w/c paper since it feels the most like a canvas surface to me and its the cheapest.
chc

Drew Davis
03-13-2000, 07:06 PM
I'd suggest sanding the painting coarsely to open up the surface and give the next layer of gesso something to "grab". People do it for wood, or cars, after all. But I can't say that I've tried it myself.