Friday, December 4, 2009

Drying Time in Oil

Blog reader Jeremy Ferguson raised a practical question:

"I'm confused about how illustrators work in oils where it's recommended that works are not varnished for 6 months. Does an illustrator get his painting done and then send it off within a few weeks without varnishing after it is dry to the touch...then varnish when he receives it back? What about commissions? Do you tell a client to wait for six months to pick up their landscape or portrait?"

Here are my thoughts, and I welcome yours in the comments:

I usually paint in oil fairly thinly using an alkyd medium (Liquin), so it nearly always dries overnight, or at the most in three or four days. If I want impasto texture and I'm on a deadline I will pretexture with quick trying priming medium. (Previous GJ post on paint texture and pretexturing (part 2) and (part 1).)

If you want to use thicker paint you can put a few drops of cobalt drier into the blob of white paint and a thick passage will set up overnight—or in a few days if it's really thick. Since white is in nearly every impasto mixture, the drying agent finds its way into all the thick passages. Don't use much, though, because it will discolor the mixtures.

Occasionally I shine a low wattage light bulb on the painting (about two feet away) overnight to hasten drying, but you have to be careful on any kind of panel to be sure it doesn't warp. Some people construct drying boxes, with low wattage bulbs to serve as heaters, which warms and dry a painting evenly.

If you have the time on a gallery painting or commissioned work, you can apply thick paint with a slower medium and wait out the drying time.

You do have to wait a few months for the finish varnish. If you varnish too early the wet paint will soak it up and still dry matte. This would be a problem for plein-air paintouts or gallery work if you don’t allow time for it to cure. If you know the buyer, you can arrange to come by and varnish it for them later.

Shipping work to illustration clients is no problem, though. If there is a passage that remains wet, you can build a crate with spacers (or ship it framed) to avoid having something touch the paint surface.


Shane White said...

Rob Howard has a rather in-depth look at varnishes and mediums that might be of interest:


Daroo said...

Stapelton Kearns has also discussed varnishing recently on his blog:

As for illustration, Do you really need to send originals? I think I remember that Greg Manchess sends his paintings to be photographed as 4x5" transparencies and then sends those to the client (They are easier to scan than an oil painting with a bunch of texture). That was several years ago -- I'm guessing there is a digital equivalent of a 4x5 " now.

I would love to see a future post about painting for reproduction, photographing artwork or trying to get a proof from your printer that has colors and contrast values that are even close to your original painting. The Dinotopia books look great to me -- how do they compare to your original paintings (in your opinion)?

Stephen James. said...

I had heard that some mediums that make oil dry quicker will eventually cause cracks? I use Cobalt drier sometimes, but I'm not sure I should keep doing it once I'm done with art school Does anyone have any advice?

Daniel Andrews said...

Liquin is great for drying for sure. I tend to enjoy a slightly tackier application so far. I use Gamlblin's Galkyd. Its a quick drying and glazing medium as well.
Many people are aware of this product I just didnt see it included so I figured id mention it.
All the best!

Julie Baroh said...

the illustrators I know here in Seattle (myself included) use Liquin as a medium and after a few days of curing, use Retouch Varnish prior to shipping out. The nice thing about Retouch is that you can still rework your piece later on (it's the only varnish situation where you can do that)prior to a final varnish.

Michael Pieczonka said...

Great info as always.. I have always wondered about how long I should wait before varnishing a painting. Awesome plein air painting too James.. would love to see how that one turned out!

TomHart said...

I use Gamvar, a Gamlin product, as a final varnish for my oils. I've been following the adice on the Gamblin website as to timing of the final varnish for quite some time. It may be wishful thinking on my part (and I know that this is a hot topic for some) but I tend to agree that, in my experience, the need for long drying times (except for impasto painting)is usually overstated. That being said, I err on the side of caution - i.e. longer drying before varnishing - if possible.

Here's what the Gamblin site says:

Q: How long do I have to wait till I varnish my painting, 6 months, 9 months, a year?

A: The answer is simple and complex. You can safely varnish when the painting is dry. But when is a painting dry?

Some paintings are dry enough to varnish after two weeks. Some are not ready for two years. If you paint thinly with fast drying colors and use a fast drying medium, in a warm and dry climate, then the painting may be ready to varnish in two weeks. But if you painted using Alizarin Crimson to make a half inch thick layer using poppy oil as a medium then the painting may not be ready to varnish in two years, if ever!

How to tell if a painting is ready to varnish is easy—just touch it. If there are impasto areas, gently press your fingernail into that impasto. If it is firm underneath the surface of the painting then it is ready for varnishing.

jpm5165 said...

This is very interesting

Jason Peck said...

Allot of painters, who have to get paintings finished for shows, and don't have time to wait six months to varnish them, will spray there paintings with a light coat of Dammar Retouch Varnish a couple of hours before the show. The painting will appear as if its varnished. A very light coat is all it takes.

The Dammar Retouch Varnish is perfectly safe and wont harm the painting. In fact, some artist use it during the actual painting process to revitalize sunken areas.

However, your work must be dry before spraying with the Dammar Retouch Varnish, otherwise, it can have unwanted effects.

If the painting is still fresh and wet, and you spray it with the retouch varnish, it will melt the paint and cause it to spread out. Sort of like misting a watercolor painting with a spray water bottle.

Tim said...

Yea Man, i just did that to a painting! It melted and lifted the layer. Entirely my own fault though, but I'm not trusting retouch varnish to paint on top of.

I love my Grahams Walnut alkyd. The right consistency and smells wonderful. I use a dropper bottle and drop one or two drops in each of my paint piles. Always dry in the morning. I found that the Galkyd simply dried too quickly! Too tacky for my taste. I got myself a liter bottle of liquin, went through that, then a liter of Galkyd, went through that, and now the Walnut stuff, and thats what I found i love the best. All my pleine air are done with it.

SarahD said...

For illustration work I use alkyd oils, which are quicker-drying, and if you use them with liquin they dry incredibly fast. I don't think the consistency and colour is as nice as true oil paint.

Unknown said...

I love that painting you're working on in the photo!

Amber said...

Holbein Duo Aqua Oils dry amazingly fast as well, no drying medium required! :)

Yuda said...

nice blog...



Erik Bongers said...

Hmmm...I shiver in horror as I read this post and comments.

I'll stick to acrylics, thank you.

James Gurney said...

Jason, and everybody: Thanks for those insights. I forgot to mention the benefits of retouch varnish, as well as the risks of varnishing a wet painting. Rockwell used to worry a lot about using retouch on wet layers, but most of his paintings have held up pretty well.

Tom, I agree that drying times of 6 or 9 months are put out there to cover people who put on thick, slow-drying paints. Most of my paintings are pretty thorougly dry in a couple weeks.

Some art photographers have asked me NOT to varnish because of reflection problems, and they've said you can create the equivalent of varnish's deepening and enriching effect in Photoshop. But my half-dried paintings are usually half-gloss and half matte, and I don't think it would work as well.

Michael and Andy, thanks for mentioning the Chop Suey painting; I posted the final painting way back in Sept. 2007:

Erik, Sarah, and Amber, thanks for mentioning the non-oil alternatives. There's a lot to choose from!

And Daroo, I'll second your recommendation for Stapleton's blog, and also Armand Cabrera's. Maybe Brad Teare will discuss this too, since thick application really makes drying time an issue.

Don Cox said...

"I'm guessing there is a digital equivalent of a 4x5 " now."

THe current professional digital cameras that have resolutions of around 37 Megapixels are roughly equivalent to 5x4. But 5x4 film is still available and can easily be scanned on a film scanner such as the Epson V750. High resolution digital cameras are very expensive.

Reflections on paintings can be controlled by putting polarizing filters over both the lights and the camera lens.

Daroo said...

Thanks Don, for the info.

I've been considering getting a 4x5 film camera for awhile now -- thinking I'd find a good deal as digital technology advances and becomes cheaper exponentially. But film prices seem to be staying pretty consistent and I've been reluctant to commit to buying all the equipment (camera, lens, lightmeter, scanner, polarizing filters for lights and cam, better lights) when a little voice in my head keeps saying, " yeah but digital technology is advancing and becoming cheaper exponentially..."

I think you are right, its still the best solution if you want to photograph art work your self.

A down and dirty solution I've used is to photograph my artwork digitally in separate sections and then stitch those different sections together into one big file in photoshop. Its a hassle because you have to have even lighting, and make sure the artwork is perpendicular to the focal plane -- but it works in a pinch. said...

Short answer to the question regarding whether or not adding cobalt drier to one's paint will cause it to crack (or wrinkle) . . . In a word, yes.

Longer answer: It does so by causing the top of the paint layer to 'dry' faster than the bottom. Linseed oil essentially oxidizes and does not 'dry'. It pulls freely available oxygen out from the air above and create an organic polymer chain called linoxyn, which is what binds the paint pigment to the underlying support. Linseed oil also shrinks as it converts into linoxyn. So when the underlying oil converts it is shrinking too,but at a lagging rate, and this is what causes the top to deflect, wrinkle, or crack. The more oil used in the paint (or medium) -- the greater the shrinkage, and the worse the end result. It may take years to become an issue, but it will happen. Most (non-alkyd) linseed oil films haven't completely converted most of the way until after 50 or more years.

This shrinkage is of the reasons to hold off on varnishing as well, if one can wait the 6 to 12 months commonly recommended.

And yes, Greg still does have his work photographed and sends the 4 x 5 to his clients. More out of a desire to control the color quality than anything else. Art Directors just have to deal with it. As for dimensional texture, there isn't as much in Greg's work as you may think. What comes across like impasto is fairly smooth and results from the way he leaves his brush pulls.

Thomas said...

Retouch varnishes do help with re-establishing the values from one session to the next, but if the varnish you use is a form of Damar, then you want to be circumspect about using it. (Assuming long-term archival issue are a concern.)

Damar eventually yellows over time, and drops in value, with some sources of the soft-resin changing more than others. So to imbed Damar between your paint layers like a multi-layered sandwich means future conservators won't be able to do much about the issue.

But hey, that's a minor issue compared to all the painters out who are still using the classic 1:1:1 medium formula taught in school, which incorporates far more Damar than any retouch does. I have a number of paintings dating back to 25 years ago which used that formula, and every one of them darkened considerably since then. (And no, those paintings cannot be bleached back up to even reasonably close to their original state by exposing them to sunlight. It is safe to say, from what I know now, it is the damar I used that contributed most to the problem.)

I cringe to think of how much of my work from the late '80s is out there in that condition.

(And James: Great blog. Good stuff to go over.)


James Gurney said...

Thomas, thanks for those incredibly informative explanations!

I noticed a lot of cracking (especially on the hair and faces) of the Waterhouse originals. It looked like the cracks had been filled in by conservators, but they were still very noticeable. Do you think these cracks were from too much oil or painting over undried layers?

Brad Teare said...

In the summer I will sometimes put a wet painting in my attic or car. Since drying is a function of oxidation (accelerated by heat) that can speed things up considerably. Be sure not to do this if you paint on panels as the panel will warp and crack the paint (Deb did that once at my suggestion. I had a lot of explaining to do!).

I recently added two entries to my blog regarding drying that might be of some interest:

I compare drying times between a combination of additives.

It is always informative to drop by. Many thanks!