Gesso over Pastel and Colourfix?

Brenda Ellis · 08-08-2005, 07:56 PM

I've got a hardboard panel (24"x36") that I had primed with ArtSpectrum Colourfix Primer. i started a sketch for a pastel on it, but have sinced changed my mind and want to use it for an oil painting. I know that Colourfix can be used as a base for oil paints, but I am concerned about the ghost remains of the pastel drawing underneath. (It's just a line drawing of a head and torso.) Do I need to remove every last trace of pastel before I re-prime the board? I will probably use acrylic gesso to reprime it.

I'm thinking I could sand it very thoroughly and get most of the pastel off. I am wondering about washing it with a wet (water) rag?

I am assuming that acrylic gesso would be okay over Colourfix Primer.

It's not as simple as just going and buying another board. I am one of those fabled starving artists.

Any suggestions? Will it be okay to sand it and then wash it and then reprime with gesso and not worry about minute traces of pastel under the gesso?

Also, at this size of board do I need to worry about any sort of support to keep it from bowing? Would gesso-ing both sides help keep it from bowing?

Am I worrying too much?

Sharon Knettell · 08-13-2005, 02:41 PM

Brenda,

Since you are covering a dry and an acrylic medium it should be no problem.

You could probably just sand the picture a bit to remove the ghost and paint over it.

I personally am not a fan of using oils over any acrylic ground, however common the practice.

Richard Budig · 08-14-2005, 09:15 AM

If you think about it, we paint over "lines," as well as paint from the previous session, all the time.

Most of us use some for of lines to place and sketch out intended subject before we start with colors. In effect, we're making lines with something (pencil, charcoal, thinned paint) and then, as time and our painting goes along, we cover them all successfully with paint -- whether that paint is dry (pastel) or wet (oil, acrylic).

I have heard, though, that over time, plain old lead pencil marks will blead up through the paint. Don't know if this is true.

I usually use vine charcoal, then wipe it off, which leaves a ghost of the image/drawing. Then, I redraw over this with a thinned raw umber/yellow ocher (or some other grayis mix), which leaves a fairly prominent line, which becomes covered and obliterated as the painting goes along. I've never had one of these beginning lines bleed up through the work.

Brenda Ellis · 08-14-2005, 04:34 PM

Richard and Sharon,

Thank you. I have sanded, then wiped the pastel off as much as I could and then just covered it with three coats of gesso, sanding lightly in between. I think it will be fine too.

Sharon, what do you usually use as your ground for oils?

This will be my first time painting on hardboard so we'll see how it goes. I want to be able able to put a lot of detail in this painting and I'm hoping the smooth surface will allow me that.

Sharon Knettell · 08-14-2005, 09:21 PM

Brenda,

I use lead primed linen. Fredricks makes a good one called RIX.

The problem with painting oil over previous attempts is that there is the problem of 'pentimento', that is oils have a tendency to get more transparent with time and reveal what is underneath them.

I just talked about a cheap and archival substrate in the Masonite thread, cheaper and easier than canvas and more archival.