The Framers Forum

Hi

I have a canvas that would crack if stretched, so would you bond it down to a backing board, if so, what adhesive should I use? Copydex has been recommended, what do you think. I do not think an adhesive backed board would provide enough sticking power.

Don't use Copydex, I used to do work for an artist, he sells his pastles artwork for thousands of ££££, he used (before I knew him) to stick his orignals down with Copydex, years later he had loads come back with stains coming through the paper,and this was blackpaper, he spent hundreds on getting them put right by a paper conserver

Do you have a heat press? Mount Cor Canvas would be ideal for this if it’s not a valuable item? Lion sell it. Doesn’t require insane heat either 60-70 degrees would be plenty. Comes with its own release paper. Anything valuable should be dealt with by an oil painting conservator really.

I believe Copydex is ammonia based and a natural rubber latex which can oxidise after a while. PVA (polyvinyl acetate) does not have this problem and may be better. I have had old canvasses to frame and have successfully bonded them to a 5mm MDF base using two coats of PVA.. Allow the first coat to soak in and when it becomes tacky apply another coat and lay the canvas on top. The next step is to lay another board on top and apply very heavy weights onto this. Leave it for at least 24 hours and it will be nicely bonded and flat, ready for framing. Of course a lot depends on the size of the artwork and the value and how archival it needs to be.

As far I can tell Copydex is an organic compound and most organic compounds will probably deteriate some day, there are a few exceptions, but I don't think that Copydex is one of them. Original renaissanse period egg tempra lasts for centures, even in out door situations, but as far as I know very few organic compounds last as long as this. PVA is what I've generally used for canvas bonding, without any difficulties to date.

I second the fitz method.

If the painting has heavy impasto or even slight lumpy bits, it's a good idea to use a foam blanket.
Release paper is also a good idea.

The canvas has no value and does not need conservational methods.
So using Fitz method with PVA. you apply one coat to the board and one directly on the reverse of the canvas?

I generally apply both coats to the base board the second after the first has become tacky effectively sealing the board and then carefully lay on the canvas smoothing it out as you go. Then place a second board the same size or slightly larger and put heavy weights onto this. (Originally learned this method from this forum some time ago (prospero and NYAF)

Broadly speaking I do much the same. Two coats of PVA on both the board and the reverse side of the canvas. Wait for the PVA to get really tacky, then position the canvas and press the canvas in place using a roller. Not hard to do!

I see that you say that the canvas would crack if stretched. There are ways of stabilising ths problem before sticking the canvas down, before sticking the canvas down. Too late to correct this issue once the canvas has been stuck down.!