Portrait Artist Forum - What about rabbit skin glue?

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What about rabbit skin glue?

Many years ago (about 35), I was to taught to size canvas with rabbit skin glue, then gesso. So of course I bought the glue when I was purchasing my original supplies. Now, I've seen no mention of it and surprisingly little info in searches on the internet. When I asked for it at the art supply store I was looked at with puzzlement, amazement, and outright horror. When I finally found some, I was asked by the clerk what it was used for. What happened?

Now a question for anyone who might know. Can I use this to glue canvas or linen to a board?

Jean

Jean,

Even though I have never tried it, I guess you could. You might have to experiment with the ratio for the consistency beacuse you do want too diluted mixture of RSG. The bonding might be enough.

Rabbit Skin Glue from what I know and used is to size canvases, boards, panels or any surface where oil paints are used. This is to prevent rotting of the surface due to the chemical change in oils. As time passes, it becomes acidic and can eat up the surface or more commonly the cotton/ linen fibers in canvases.

RSG is also mixed with chalk ground, pigments, oil to make classic gesso.

Hi Joseph,

Thanks for the info. Do you or anyone else know more about the acidic nature and destruction of fibers? I don't want to use this and have the fabric rot later. I have two paintings that were sized like this 35 years ago and the fabric hasn't rotted, even though the paintings are pretty rotten (I was a little intense back then).

Jean

Hi Jean,

If there is sizing then it is ok. RSG, gesso acrylic or classic. It is a problem when there is no sizing at all. It is when the fibers are in direct contact with oils and mediums that causes chemical reactions which will weaken the fibers.

Just in passing, I note these remarks from the Gamblin site, discovered on an unrelated pearl dive:

Quote:

SIZE

Before a oil painting ground is applied, the canvas is sealed with a size. The size seals the porous fabric and isolates it from the ground and/or oil paints. Linen and cotton will prematurely rot without a size layer. Only fabric supports need sizing. Panels only need to have a ground. Acrylic gesso does not require a size.

PVA Size (poly vinyl acetate glue), diluted with distilled water, is a contemporary size for fabric support. Conservation scientists recommend painters use neutral pH PVA size on linen and canvas instead of rabbit skin glue. PVA provides a good size layer that seals the fabric but does not re absorb atmospheric moisture, swell and shrink like rabbit skin glue does. Painters who want to paint directly on a size, apply one layer of PVA Size to the front and back of the fabric.

We acknowledge and appreciate the research of the Canadian Conservation Institute that helps painters and conservators identify the best PVA to use.

Rabbit Skin Glue is the traditional size for fabric support. Conservation scientists caution painters that rabbit skin glue absorbs atmospheric moisture on damp days and swells; gives off moisture on dry days and shrinks. This movement of the size layer can cause aged oil paintings to crack, according to the Smithsonian Center for Materials Research and Education

Thank you Steven, this is the kind of info I was looking for. It may explain why my old paintings have cracked. I still have two very old paintings from my college days and both have cracked severely. Along with the fact that I have done nothing to protect them, they were all sized with rabbit skin glue.

Jean