Comments on: Shellac Sizing Test for Oil Paint on Paper

By: Hide Glue Sizing of Paper for Oils « Artwork by D. B. Clemons

Hide Glue Sizing of Paper for Oils « Artwork by D. B. Clemons — Tue, 22 Dec 2009 17:22:34 +0000

[...] to test that out. My preferred sizing for paper, which I’ve written about before, is actually shellac, but hide glue can work well [...]

By: Mary

Mary — Thu, 12 Nov 2009 12:57:41 +0000

Thanks for the recipe. I have a supplier and plenty of denatured alcohol so I should be good to go. I do love the surface shellac provides!

By: dbclemons

dbclemons — Thu, 12 Nov 2009 01:26:31 +0000

Mary, the shellac solution is described as a “pound cut,” meaning one pound of shellac diluted in one gallon of alcohol. Breaking that quanitity down to a more manageable size, I usually use a 2 pound cut which would be 2 ounces of flakes to 8 ounces of alcohol. If you’re using a metric system, you’re on your own, but it doesn’t really need to be that precise, and I’ve been making it up for so long I typically just go by sight rather than measuring.
It’s also good to use de-waxed shellac flakes and get as light a color as possible for sizing the paper. The terms for the light color vary quite a bit from bleached, clear, white, extra blonde, etc. From what I’ve read, bleaching which can weaken the shellac somewhat, but makes it clearer.

By: Mary

Mary — Wed, 11 Nov 2009 21:48:50 +0000

I think he may be referring to the method of making the shellac…

That does sound like a simple process using the flakes in a stocking. My question, what is the ratio of flakes to alchohol?

By: dbclemons

dbclemons — Wed, 11 Nov 2009 20:19:25 +0000

Thanks for the reply, Robert. If you’re calling commercial shellac “undoubtably better,” you have no way of knowing that. I have plenty of room for doubt in pre-mixed shellac, and that’s the whole point. It’s possible whatever they add to it won’t be detrimental to my artwork. Without knowing everything that’s in it, I can’t say. When I make it myself I know it’s okay. As for being easier to use, I don’t consider dissolving the flakes in alcohol as difficult, and once it’s made it’s as easy to use as any commercial brand. There’s a cafe up the street from me that makes a decent omlette, but mine are better.

By: robert meredith

robert meredith — Wed, 11 Nov 2009 17:29:02 +0000

Shellac is the best sealer there is for porus surfaces. It will only disolve in alcohol and once dry, 20-25 minutes, is totally impervious to other solvents or oil. Shellac may be bought in spray cans or by the pint or quart. It is available as amber or blond. For paper it should be liberally thinned with denatured alcohol. Ten-twenty percent shellac should be fine. This is a lot easier and undoubtably better than what you are doing. To make shellac from shellac flakes place flakes in the toe of a stocking and suspend overnight in a tightly sealed jar of denatured alcohol. The stocking retains the impurities. Denatured alcohol is hydroscopic and absorbes moisture from the atmosphere so keep shellac tightly sealed.

By: Dimitris C. Milionis

Dimitris C. Milionis — Sat, 24 Oct 2009 09:03:39 +0000

check for different qualities

By: Mary

Mary — Sat, 24 Oct 2009 00:36:33 +0000

Thanks for the info, I’ll try your recipe out.

I agree, paintings do fall apart for several reasons and we must keep the conservators in business anyway! As long as it doesn’t flake off in my lifetime, so I’ll definitely try sanding.

By: dbclemons

dbclemons — Fri, 23 Oct 2009 20:09:21 +0000

Mary, some commercial brands of shellac have additives to extend their shelf-life, but without knowing what’s in it there’s no way of knowing what that will do to the painting. Fresh shellac is not difficult to make, and is much cheaper in the long run. There may be some places online that will make it up fresh for you.

Metal plates have little to no tooth or absorbency, and old oil paintings on them are in excellent condition. Any number of factors can be related to the failure of a painting over time, including how well the materials are made, applied, or their quality.

Have you sanded your shellac’d panels? A quick sanding with finegrit sandpaper can help give more tooth for the paint. One coat won’t likely be much of a barrier if you’re using 1-2 pound shellac.

A lightfast test might show how well shellac will last. Place a small sample of quality paper sized with 2-3 coats of clear de-waxed shellac in a south-facing window for about 6-12 months, and see how well it holds up. You could also apply some oil paint to it to see how well that adheres.

By: Mary

Mary — Fri, 23 Oct 2009 15:48:20 +0000

HI David,

Thank you for posting this information and taking the time to post your test. I love painting on a shellac ground both on paper and on panel. If using a good rag paper I doubt cracking will really be an issue as the paper absorbs. Is there a real reason to make ones own shellac? Is store bought inferior?

Also, while researching this topic, I came up with the following comment from someone else and I wonder if you have an answer for his claim:

“To adhere properly, oil paint requires a surface that has tooth and absorbency. Protecting the surface with shellac, fixative, acrylic varnish or acrylic paint will protect the paper but will not provide a sympathetic ground. Norman Rockwell prepared many of his illustration boards with shellac before painting with oil in the 1920s. Now many of these paintings are in poor condition after only 80 years – a short time in the life of a painting.”

Sometimes I have notice when working on wood that the paint scratches more easily, so I do wonder if perhaps there isn’t enough adhesion so I am experimenting using less shellac (one coat) so that the surface has more tooth. This appears to be working better.

Thanks again,
Mary