Canvas Problem

Enzie Shahmiri · 01-27-2003, 02:28 PM

This is an old painting I once started and never finished. It was started many years ago, without a proper underpainting or tinting of canvas.

I have since worked on it, and many layers later, still see little pin-holes where the light shines through it. Another thing I have discovered are stains on the back that look like oil that has seeped to the backside of the canvas.

First, I'd like to know if it is OK to put a layer of paint on the back, and, if so, should it be diluted with a medium or impasto? What color do you recommend to avoid darkening the lights in the front?

Second, could the oil residue on the back be due to overuse of Liquin?

Your help would be appreciated.

Enzie Shahmiri · 01-27-2003, 02:32 PM

The holes don't show up as clearly on the uploaded image. They are the areas that look like lighter pixels, where the color should not be broken.

Michael Georges · 01-27-2003, 04:44 PM

Enzie:

Am a little unclear if you intend to continue on this work or start a new work over it.

My baseline advice is that if you are suspicious of the stains on the back and the overall quality and survivability of the canvas, then you would do well to abandon it for a new canvas and begin the work again. If the oil has gotten to the fabric on the back, then it will rot it away over time.

Also, if you plan to start a new work, then definitely don't use this canvas as eventually the work underneath will show through. That combined with the stains on the back...new canvas.

Enzie Shahmiri · 01-27-2003, 04:50 PM

Dear Michael,

I have been working on it, but now I wonder if that is such a good idea, after what you said.

Do you know what could cause the "leakage"?

Michael Georges · 01-27-2003, 05:44 PM

Is this a commercial canvas? If so, then that is the problem. Many of the commercially produced canvases have a very light coating of gesso on them (not high quality gesso either) and you end up with pin holes. If you cannot stretch your own, then I recommend applying two coats of good professional gesso over any commercial canvases you buy.

Another question is, do the pin holes match the stains? If so, then the rot is already in progress.

Enzie Shahmiri · 01-27-2003, 07:44 PM

Micheal,

The canvas is commercial and as far as I remember I did not apply additional Gesso. So this explains the pin holes!

The unfinished piece had hung on a wall in a dark, dry room next to the garage (2nd artroom) for about 4 years. I am pretty sure it is not rotting. I did some restoration on early 1900 paintings that went through hardships, before they got to me. The stains don't have the same look, no clouding in the front and no loss or discoloration of pigment either.

I think it is the Liquin that has seeped through. It seems to be more in areas where the stained glass is and I know I that I used thin Liquin washes in those areas. Sort of like you would do watercolor washes. Maybe I used too much medium compared to pigment?!

The question then would be: can a coat of gesso be applied on the back, once the Liquin dries?

Mari DeRuntz · 01-28-2003, 12:09 AM

Enzie,

If you have oily spots showing on the back of the canvas, the paint is already soaking into the canvas ground, and Michael is right, it will rot. If the Liquin seeped through, so did the oil. In fact, even properly primed cotton canvas can show signs of decomposition quite quickly.

Nothing you apply to the back will adhere to an "oily" ground or help in any manner. The purpose of a glue or acrylic primer is to seal the fibers from the harmful affects of the oil; if the oil is showing through the back, it has penetrated the fibers, and decomposition is just a matter of time.

When I first read your post, it was unclear whether the ground was ever primed. I'm sure you now know you cannot paint in oil on raw paper or cotton or linen; the fibers do not hold up to oil exposure. If you cannot remember the history of the canvas, better safe than sorry; start over.

"Foxing" might also be the culprit; small growths of mold bloom on the surface of improperly stored or primed surfaces.

Check out the thread Chris Saper started on "Putting failures to work" for great suggestions on what to do with those old canvasses which for whatever reason are no longer viable.

Enzie Shahmiri · 01-28-2003, 10:59 PM

Hi Mari,

Thank you for your response. I have been going through a huge volume of an art restoration book and it is definitely not foxing or blooming, nor oxidizing either.

I used to buy Frederick primed canvas from art stores, and although the primer might have been less than ideal, it did have some on it. This leaves me to believe that the canvas must have gone through some sort of a stress to force the fibers apart, thus the holes. Since the fibers are no longer densely weaved, it would allow for the Liquin and the oils to seep through to the other side.

I think both you and Michael might be right in the assumption that this can lead to deterioration down the line. Whatever the cause for the seeping of the oils, I agree with you it's best to not work on it any further.